Malaria awareness of adults in high, moderate and low transmission settings: A cross-sectional study in rural East Nusa Tenggara Province, Indonesia.

INTRODUCTION: The 2009 Indonesian roadmap to malaria elimination indicated that the nation had been progressing towards achieving malaria elimination by 2030. Currently, most of the districts in the western part of Indonesia have eliminated malaria; however, none of the districts in the East Nusa Tenggara Province (ENTP) have met these set targets. This study aimed to investigate the status of malaria awareness of rural adults in the ENTP.
METHODS: A community-based cross-sectional study was conducted between October and December 2019 in high, moderate, and low malaria-endemic settings (MESs) in the ENTP. After obtaining informed consent, data were collected using an interviewer-administered structure questionnaire among 1503 participants recruited by a multi-stage cluster sampling method. A malaria awareness index was developed based on ten questions. A binary logistic regression method was applied to investigate the significance of any association between malaria awareness and the different MESs.
RESULTS: The participation rate of the study was 99.5%. Of this number, 51.4% were female and 45.5% had completed primary education. The malaria awareness index was significantly low (48.8%, 95% confidence interval [CI]: 45.2-52.4). Malaria awareness of rural adults residing in low endemic settings was two times higher than for those living in high endemic settings (adjusted odds ratio [AOR]: 2.41, 95% CI: 1.81-3.21) and the basic malaria knowledge of participants living in low malaria-endemic settings was almost four times higher than that in high endemic settings (AOR: 3.75, 95% CI: 2.75-5.11). Of the total participants, 81.3% (95% CI: 79.1-83.5) were aware that malaria could be prevented and 75.1% (95% CI: 72.6-77.6) knew at least one prevention measure. Overall, the awareness of fever as the main symptom of malaria, mosquito bites as the transmission mode of malaria, and seeking treatment within 24 hours of suffering from malaria was poor at 37.9% (95% CI: 33.9-41.9), 59.1% (95% CI: 55.9-62.3), and 46.0% (95% CI: 42.3-49.7), respectively. The poor level of awareness was significantly different amongst the three MESs, with the lowest levels of awareness in the high endemic setting.
CONCLUSION: Malaria awareness of rural adults needs to be improved to address Indonesia's national roadmap for malaria elimination. Results indicated that public health programs at a local government level should incorporate the malaria awareness index in their key strategic intervention to address malaria awareness.

Introduction

Malaria is a major global health problem with an estimated 1.2 billion people living at a high risk of being infected [1]. However, malaria cases and associated deaths have decreased in the last decade: from 2010 to 2018, the total number of malaria cases decreased by approximately 1% per year and deaths due to malaria declined by 5% annually [1]. The number of countries reporting less than 51 cases of local transmission increased from 5 countries in 2010 to 11 countries in 2018 [2]. Countries with zero local transmission in the last three consecutive years are eligible to request malaria elimination certification from the World Health Organization (WHO) [2]. Two countries, the Maldives and Sri Lanka, have been certified as malaria-free areas by the WHO Regional Office for South-East Asia (SEARO) [3]. In alignment with the global action plan for a malaria-free world [4] and the Global Technical Strategy for Malaria Elimination [5], the WHO SEARO action plan indicates that all countries in the region will be malaria-free zones by 2030 [3].

The roadmap for malaria elimination in Indonesia was proposed in April 2009 and aimed to eliminate malaria by 2030 [6, 7]. All malaria-endemic districts in Indonesia were divided into four categories based on the annual prevalence incidence (API). Of the 514 districts in the country, 298 (58%) were categorized as malaria elimination districts in 2019 [8]. All districts in the provinces of the Special Capital Region of Jakarta, Bali and East Java have been categorized as malaria elimination areas, whereas none of the districts from five provinces in the eastern part of Indonesia such as Papua, West Papua, Maluku, North Maluku, and the East Nusa Tenggara Province (ENTP) have achieved this categorization [8].

The ENTP is a province with an API value that is five times higher than the national Indonesian level [9]. This province has 21 districts and one municipality [10]. Fourteen districts and the municipality are low endemic, while four and three districts have been classified as moderate and high endemic, respectively [8]. In line with the national commitment to eliminate malaria by 2030, there have been various efforts of the local authorities to support malaria elimination in this province. This has included increasing the coverage of artemisinin-based combination therapy (ACT) as the first line of malaria treatment from 55% in 2013 [11] to 83.1% in 2018 [9], and screening pregnant women for malaria during their first visit to local health centres [12]. For controlling mosquitoes, the introduction of treated bed nets has been implemented in most of the districts in the region since 2008 [13], the mass distribution of long-lasting insecticide–treated nets (LLINs) in 15 districts since 2017 [14], and the use of special repellent [15]. However, the number of malaria cases is still high (12,909 cases) [8], indicating that these interventions may be ineffective and that the implementation of these interventions may depend on community behavior; however, there has been limited investigation of these factors in this province. Community knowledge and behavior play significant roles in supporting malaria elimination [16, 17]: high levels of malaria awareness in communities enables them to improve self-protection [18], seek early treatment [19], and reduce malaria prevalence [20], consequently speeding up malaria elimination [21].

Several studies concerning malaria knowledge have been undertaken in Indonesia since the declaration of the national commitment to eliminate malaria [22-25]. However, knowledge of LLINs, which are the most effective tools to prevent malaria [26] and are currently adopted as the primary vector control intervention in many parts of Indonesia [7], was not investigated in these studies. Additionally, most of the studies were conducted in the western part of Indonesia, which has been classified as a malaria elimination area. Studies were also conducted at the sub-district and village levels. One population-based study on 4,050 participants in North Maluku province revealed that only about half of the respondents knew about symptoms of malaria and the majority of participants (98%) did not know the main cause of malaria [24]. However, approximately 50% of the participants were less than 18 years old and were hardly suitable candidates for measuring the level of knowledge of a particular community.

Various studies on malaria knowledge have been conducted in the ENTP [12, 27–29]. Most of these studies were conducted at the village and subdistrict levels. One population study covering only pregnant women in a high malaria-endemic area of the province indicated that there was a low level of malaria prevention knowledge, particularly relating to LLINs [12]. Another population-level study on community behaviour relating to malaria was conducted in the ENTP in 2018 [29]. However, this study only investigated malaria prevention practices of the rural community and malaria prevention awareness in different MESs was not compared. To date, the investigation of malaria knowledge relating to the symptoms, transmission mode, and prevention method, and the malaria treatment-seeking behaviour of rural adults in different types of malaria-endemic settings in the ENTP has not been performed. Investigation of malaria awareness in rural communities is critical for Indonesia, considering that 52% of malaria cases in the country were contributed by rural communities [9] and that there are variations in malaria prevention practice amongst provinces in the country [29]. An understanding of the level of malaria knowledge in rural communities and determining which MES is most vulnerable is essential for the development and implementation of evidence-based strategies to accelerate progress towards malaria elimination in the province. The present study aimed to fill this gap by investigating malaria awareness of rural adults in three different MESs to support the national commitment of Indonesia’s government to eliminate malaria by 2030.

Materials and methods

Study sites

The ENTP is one of 34 provinces in Indonesia, in the eastern part of the country. The total population of the ENTP is 5.3 million, accounting for about 2.04% of the total population of Indonesia [10]. The ratio of male to female (50.5% to 49.5%) is comparable with that of Indonesia (50.2% to 49.8%). The area of the province is 47,931.54 km2, located between 1180° and 1250° east longitudes and between 80° and 120° south latitudes, with a population density of 114 people per square kilometer [10]. This community-based cross-sectional study was conducted from October to December 2019 in three districts out of 21 districts and one municipality in the province. They were East Sumba, Belu, and East Manggarai districts representing high, moderate, and low MESs, respectively [30], as shown in Fig 1.

Fig 1

Map of study sites.

Sample size calculation

The initial sample size (n0) was calculated based on the formula n0 = Z2P(1-P)/d2 for the prevalence study of a cross-sectional study [31]. The parameters Z is the value of standard score of 95% confidence interval (1.96), P is the prevalence of malaria study in the ENTP conducted by the Indonesian government (1.99%) [9], and d is the relative precision which is 0.01125. Therefore, the initial sample size n0 was equal to 592. The design effect was accounted for due to cluster sampling by the multiplication of a factor of 2.16. By considering the participation rate of 85%, the final sample size was 1503 adults. The sample size calculation was described previously [32].

Sampling technique

All adults in ENTP were the source population, and all adults in the selected three districts were the study population. A multi-stage cluster sampling procedure with a systematic random sampling procedure at the final cluster level 4 was applied to recruit adults from the three districts. At cluster level 1, three districts were selected out of 22 in the ENTP based on the annual parasite incidence (API) of malaria, at cluster level 2, three sub-districts were randomly chosen from each selected district. At cluster level 3, the number of villages selected from each sub-district was based on their relative populations. At the final cluster level, a systematic random sampling technique was used to recruit 20–40 participants per village, proportionate to the population size of each village. In each selected household, one head of the family of any gender who provided consent to participate voluntarily was included in the study. If the household head, either husband or wife, was absent, residents over 18 years of age could serve as study participants [33]. We excluded anyone under the age of 18 years old from the study.

Data collection tools and techniques

An interviewer-administered questionnaire adapted from a validated questionnaire [34, 35] was used to collect data for this study. The English version of the questionnaire was translated into the local language by the lead author of this article and a local language expert. They then combined the two translated versions. The combined version of the questionnaire was then tested on 30 participants before finalization. The data were collected in collaboration with local nurses who were residents in the study area. Nine local nurses, three nurses from each district conducted face-to-face interviews with participants based on the guidance of the structured questionnaire. The data collection process was monitored strictly by the investigator daily to check the questionnaire’s completeness. Data on the socio-demographic variables and general knowledge of malaria was collected during the interview.

Malaria awareness measures

Ten questions were used to assess the malaria understanding and knowledge of rural adults. The first three questions explored participants’ basic understanding of malaria, including whether they had heard of malaria, whether malaria was dangerous to their health, and whether malaria could be prevented. The responses options for these questions were yes or no, with yes receiving a score of one. Overall, participants obtained a score of three if they correctly answered all three questions. The total score for participants’ basic understanding of malaria was evaluated following the approach in previous studies [36, 37]. Participants who correctly answered at least two of the first three questions were categorized as having basic malaria understanding; participants were otherwise categorized as having no basic malaria understanding.

The next seven questions also explored basic malaria knowledge, including whether participants could identify: 1) the main symptom and cause of malaria, 2) protective measures to prevent malaria, and 3) the importance of seeking treatment for malaria within 24 hours after the onset of the symptoms. Participants who could identify fever as the main symptom [38] and mosquito bites as the main cause of malaria [39, 40] obtained a score of one for each. Participants who mentioned sleeping under non-LLINs, sleeping under LLINs, using mosquito coils, or keeping the house clean as methods to prevent malaria also achieved a score of one for each. Finally, participants who mentioned seeking malaria treatment within 24 hours [41] obtained a score of one. A total score of seven was possible if participants correctly answered all seven questions. The total score for participants’ basic malaria knowledge was further evaluated following the procedure described in previous studies [36, 37]. Participants who correctly answered at least five of these seven questions were categorized as having basic malaria knowledge.

Overall, each participant could gain a score of ten if they correctly answered all ten questions. The total score for the ten questions was evaluated following the approach described in previous studies [36, 37]. Participants with scores of above 80%, 60–79%, 1–59%, and 0 were classified as having excellent, good, poor, and zero malaria knowledge, respectively; participants in the excellent and good groups were categorized as having malaria awareness while those who were in the poor and zero groups were classified as being unaware of malaria [36, 37].

Socio-demographic covariates

Socio-demographic information including gender, age, education level, and socioeconomic status (SES) was collected. Gender was categorized as male and female. Age was classified into five groups, < 30, 30–40, 40–50, 50–60, and > 60 years old. The level of education was categorized as no education, primary school (grade 1 to 6), junior high school (grade 7 to 9), senior high school (grade 10 to 12), and diploma or above. The SES group was assessed according to ownership of durable assets and housing characteristics [42]. In each selected household, the participant was asked about their ownership of ten durable asset items including radio, television, electricity, bike, motorcycle, handphone, fridge, tractor, generator, and car. Housing characteristics were evaluated according to access to water taps in dwellings and the main material of the house, with houses having cement floors and walls categorized as modern houses and others as non-modern houses. In total, 12 items were used to construct the SES level and three SES levels were defined by counting the overall ownership of these items. Low SES was defined as having zero or one item; moderate SES was defined as owning two to four items and high SES was defined as having more than four items, following the approach of Zafar et al. [42].

Statistical analyses

The participants’ socio-demographic characteristics including gender, age group, education level, and SES were reported using descriptive statistics. The proportion of participants answering each question correctly and its 95% confidence interval (CI) were computed for each MES. The association between the MES and responses to the 10 questions was explored by the chi-square method. This approach was further applied to initially evaluate the association of basic malaria understanding, basic malaria knowledge, the level of malaria knowledge, and the level of malaria awareness amongst the three types of MESs. A univariate and multivariate binary logistic regression model was applied to evaluate the association between the dependent and the independent variables. The associations were reported as odds ratio with its 95% CI. Multicollinearity tests amongst the independent variables were done before multivariate analysis was conducted. The Hosman and Lemeshow test evaluated the overall model fitness with a significance level of p < 0.05. Wald statistic was used to assess the significance of the individual covariates in the model. In the univariate binary logistic regression, all variables having a p-value < 0.10 were included in the multivariate analysis to control confounding factors [43]. After controlling the confounding variables, all variables with a p-value of 0.05 or less were considered statistically significant as a predictor of outcomes variables. The direction and strength of association between explanatory variables and endpoints were estimated by adjusting the odds ratio. Statistical software SPSS version 27 (SPSS Inc.) was used for analyses.

Ethics approval

The research was conducted in accordance with the tenets of The Declaration of Helsinki. The study was approved by the Human Ethics Committee of Swinburne University of Technology, Australia (Reference: 20191428–1490) and the Health Research Ethics Committee, National Institute of Health Research and Development (HERC-NIHRD), Ministry of Health of Indonesia (Reference: LB.02.01/2/KE.418/2019). Written consent was obtained from participants who had the full capacity to give voluntary consent in their own right based on the provision of sufficient information. Participants who were unable to read the consent documentation authorized their spouse or immediate family member to read the consent form and sign it on their behalf. Participants were informed of their right to withdraw from the study at any stage or to restrict the use of their data in the analysis.

Results

Demographic characteristics of the study population

The participation rate of this study was 99.5% (1495 out of 1503). Of all the participants aged between 18 and 89 years (mean: 43.8 years, standard deviation: 12.8 years), 51.4% was female. In terms of educational attainment, most respondents had completed primary education (45.4%) and almost 20% did not have any formal education. The disparity of education distribution amongst these three settings was evident, with 35% having no education in the high MES compared to 2.6% in the low MES. Most participants (57.5%) were categorized as moderate SES. The socio-demographic characteristics of the participants based on the MES are shown in Table 1.

Table 1

Distribution of study participants and participants from a national representative sample in three different MES in the East Nusa Tenggara Province (ENTP), Indonesia.

			Malaria Endemic Setting (MES)b
Characteristic	ENTP	Total n (%)	High	Moderate	Low
Total	5,456,203	1,495	495 (33.1)	500 (33.4)	500 (33.4)
Gender [10]
Females	50.5	768 (51.4)	264 (53.3)	267 (53.4)	237 (47.4)
Males	49.5	727 (48.6)	231 (46.7)	233 (46.6)	263 (52.6)
aAge Group [10]
< 30	39.9	205 (13.7)	79 (16.0)	64 (12.8)	62 (12.4)
30–39	18.9	418 (28.0)	137 (27.7)	108 (21.6)	173 (34.6)
40–49	16.4	371 (24.8)	138 (27.9)	123 (24.6)	110 (22.0)
50–59	12.7	295 (19.7)	69 (13.9)	129 (25.8)	97 (19.4)
> 60	12.1	206 (13.8)	72 (14.5)	76 (15.2)	58 (11.6)
Education Level [10]
No education	30.4	279 (18.7)	173 (35.0)	93 (18.6)	13 (2.60)
Primary school	27.5	678 (45.4)	205 (41.4)	205 (41.0)	268 (53.6)
Junior High school	16	229 (15.3)	47 (9.50)	97 (19.4)	85 (17.0)
Senior High school	18.6	210 (14.1)	53 (10.7)	83 (16.6)	74 (14.8)
Diploma or above	7.6	99 (6.60)	17 (3.40)	22 (4.40)	60 (12.0)
Socio-Economic Status [44]
Poor	89.6	449 (30.0)	151 (30.5)	105 (21.0)	193 (38.6)
Average	4.80	860 (57.5)	286 (57.8)	331 (66.2)	243 (48.6)
Rich	5.70	186 (12.4)	58 (11.7)	64 (12.8)	64 (12.8)

a The percentage of people in different age groups at the national level was calculated based on people aged > 15 years

b High: East Sumba District, Moderate: Belu District, Low: East Manggarai District.

Malaria knowledge by malaria-endemic setting in the ENTP

The differences in various aspects of malaria knowledge amongst the three different MESs are shown in Table 2. In terms of basic malaria understanding, the percentage of respondents who had heard of malaria and were aware that malaria could be prevented was high, accounting for 86.1% (95% confidence interval [CI]: 84.2–88.0, p < 0.001) and 81.3% (95% CI: 79.1–83.5, p < 0.001), respectively, while understanding of the dangerous effect of malaria on health was only 64.1% (95% CI: 61.1–67.1, p < 0.001)—this was highest in the low MES (73.4%; 95% CI: 68.9–77.9, p < 0.001) and lowest in the moderate MES (45.8%; 95% CI: 39.3–52.3).

Table 2

Distribution of malaria knowledge of rural adults in three different malaria-endemic settings (MESs) in the East Nusa Tenggara Province (ENTP), Indonesia.

	Items	Total, n = 1,495	MESb, n (%) [95%CI]c			p-value
			High, n = 495	Moderate, n = 500	Low, n = 500
	Part I: Basic malaria understanding
1	Heard of malaria	1,287 (86.1) [84.2, 88.0]	480 (97.0) [95.5, 98.5]	398 (79.6) [75.6, 83.6]	409 (81.8) [78.1, 85.5]	< 0.001
2	Malaria has a dangerous effect on health	959 (64.1) [61.1, 67.1]	363 (73.3) [68.7, 77.9]	229 (45.8) [39.3, 52.3]	367 (73.4) [68.9, 77.9]	< 0.001
3	Malaria can be prevented	1,216 (81.3) [79.1, 83.5]	466 (94.1) [92.0, 96.2]	362 (72.4) [67.8, 77.0]	388 (77.6) [73.5, 81.7]	< 0.001
	Part II: Basic malaria knowledge
4	Main symptom of malaria	567 (37.9) [33.9, 41.9]	82 (16.6) [8.50, 24.7]	234 (46.8) [40.4, 53.2]	251 (50.2) [44.0, 56.4]	< 0.001
5	Transmission mode of malaria	883 (59.1) [55.9, 62.3]	320 (64.6) [59.4, 69.8]	294 (58.8) [53.2, 64.4]	269 (53.8) [47.8, 59.8]	0.002
	Prevention knowledge
6	Sleeping under non-LLINs	349 (23.3) [18.9, 27.7]	26 (5.30) [0.00, 13.9]	55 (11.0) [2.70, 19.3]	268 (53.6) [47.6, 59.6]	< 0.001
7	Sleeping under LLINs	752 (50.3) [46.7, 53.9]	358 (72.3) [67.7, 76.9]	210 (42.0) [35.3, 48.7]	184 (36.8) [29.8, 43.8]	< 0.001
8	Using mosquito coils	344 (23.0) [18.6, 27.4]	113 (22.8) [15.1, 30.5]	120 (24.0) [16.4, 31.6]	111 (22.2) [14.5, 29.9]	0.79
9	Keeping house clean	539 (36.1) [32.0, 40.2]	123 (24.8) [17.2, 32.4]	137 (27.4) [19.9, 34.9]	279 (55.8) [50.0, 61.6]	< 0.001
	Knowing at least one prevention measure	1,122 (75.1) [72.6, 77.6]	424 (85.7) [82.4, 89.0]	344 (68.8) [63.9, 73.7]	354 (70.8) [66.1, 75.5]	< 0.001
	Knowing at least two prevention measures	592 (39.6) [35.7, 43.5]	160 (32.3) [25.1, 39.5]	123 (24.6) [17.0, 32.2]	309 (61.8) [56.4, 67.2]	< 0.001
10	Seeking treatment for malaria a	687 (46.0) [42.3, 49.7]	170 (34.3) [27.2, 41.4]	223 (44.6) [38.1, 51.1]	294 (58.8) [53.2, 64.4]	< 0.001
	Basic malaria understanding*	1,242 (83.1) [81.0, 85.2]	472 (95.4) [93.5, 97.3]	363 (72.6) [68.0, 77.2]	407 (81.4) [77.6, 85.2]	< 0.001
	Basic malaria knowledge†	523 (35.0) [30.9, 39.1]	94 (19.0) [11.1, 26.9]	168 (33.6) [26.5, 40.7]	261 (52.2) [46.1, 58.3]	< 0.001
	Malaria awareness‡	730 (48.8) [45.2, 52.4]	184 (37.2) [30.2, 44.2]	222 (44.4) [37.9, 50.9]	324 (64.8) [59.6, 70.0]	< 0.001

a Seeking treatment within 24 hours when participants or their family members suffered from malaria symptoms.

b High: East Sumba District; moderate: Belu District; low: East Manggarai District

c 95% confidence interval of proportion.

* Total score for questions 1–3.

† Total score for questions 4–7.

‡ Total score for questions 1–10.

In terms of basic malaria knowledge, the awareness of fever as the main symptom of malaria was low (37.9%; 95% CI: 33.9–41.9, p < 0.001); this was 50.2% (95% CI: 44.0–56.4, p < 0.001) in the low MES, 46.8% (95% CI: 40.4–53.2, p < 0.001) in the moderate MES and 16.6%, (95% CI: 8.50–24.7, p < 0.001) in the high MES (P < 0.001). The knowledge of mosquito bites as the main cause of malaria was also low (59.1%; 95% CI: 55.9–62.3, p < 0.002), which was highest in the high MES (64.6%; 95% CI: 59.4–69.8, p < 0.002) and lowest in the low MES (53.8%; 95% CI: 47.8–59.8, p < 0.002).

The percentage of participants who knew at least one malaria prevention measure was high, at 75.1% (95% CI: 72.6–7.6, p < 0.001), and was 85.7% (95% CI: 82.4–89.0, p < 0.001) in the high MES, 70.8% (95% CI: 66.1–5.5, p < 0.001) in the low MES and 68.8%, (95% CI: 63.9–73.7, p < 0.001) in the moderate MESs (P < 0.001). However, the proportion of participants who knew at least two malaria prevention measures was low at only 39.6% (95% CI: 35.7–43.5, p < 0.001); the percentage was highest at 61.8% (95% CI: 56.4–67.2, p < 0.001) in the low MES, followed by 32.3% (95% CI: 25.1–39.5, p < 0.001) in the high MES and 24.6% (95% CI: 17.0–32.2, p < 0.001) in the moderate MES (P < 0.001). There was also a low percentage of participants who knew about sleeping under LLINs to prevent malaria, at 50.3% (95% CI: 46.7–53.9, p < 0.001); the percentage was highest at 72.3% (95% CI: 67.7–76.9, p < 0.001) in the high MES, followed by 42% (95% CI: 35.3–48.7, p < 0.001) in the moderate and 36.8% (95% CI: 29.8–43.8, p < 0.001) in the low MES.

In terms of malaria treatment-seeking behavior, the proportion of participants who were aware of the importance of seeking treatment within 24 hours if they or their family members suffered from malaria symptoms was also low at 46% (95% CI: 42.3–49.7, p < 0.001); this was highest at 58.8% (95% CI: 53.2–64.4, p < 0.001) in the low MES, 44.6% (95% CI: 38.1–51.1, p < 0.001) in the moderate MES and 34.3% (95% CI: 27.2–41.4, p < 0.001) in the high MES. The levels of awareness in the different MESs were significantly different (p < 0.001).

Overall, 48.8% of rural adults in the ENTP had a malaria awareness score of above 60% and only 17.4% had a score of above 80% correct. The proportion of participants having a poor malaria knowledge score was high at 42.9%, with 60.4% in the high MES followed by 44.2% in the moderate MES and 24.4% in the low MES, as shown in Fig 2.

Fig 2

Distribution of malaria knowledge scores amongst participants.

Malaria awareness of rural adults in the ENTP

Among the participants, the percentage of basic malaria understanding was very high at 83.1% (95% CI: 81.0–85.2, p < 0.001) with 95.4% (95% CI: 93.5–97.3, p < 0.001) in the high MES, 72.6% (95% CI: 68.0–77.2, p < 0.001) in the moderate MES and 81.4% (95% CI: 77.6–85.2) in the low MES (P < 0.001). The proportion of rural adults with basic malaria knowledge was low at 35% (95% CI: 30.9–39.1, p < 0.001), with the highest proportion of 52.2% (95% CI: 46.1–58.3, p < 0.001) in the low API, followed by 33.6% (95% CI: 26.5–40.7, p < 0.001) and 19.0% (95% CI: 11.1–26.9, p < 0.001) in the moderate and high MESs, respectively.

Overall, only 48.8% (95% CI: 45.2–52.4, p < 0.001) of rural adults in the ENTP had malaria awareness. The malaria awareness in low the MES was the highest at 64.8% (95% CI: 59.6–70.0, p < 0.001) followed by 44.4% (95% CI: 37.9–50.9, p < 0.001) in the moderate MES and 37.2% (95% CI: 30.2–44.2, p < 0.001) in the high MES. The difference in awareness was statistically significant amongst these three settings (P < 0.001) as shown in Table 2.

The highest proportion of participants with basic malaria understanding was in the high MES (95.4%), while the highest proportion of participants with basic malaria knowledge and malaria awareness was in low the MES, at 52.2% and 64.8%, respectively. After adjusting all confounding variables, MES, education level, and SES were significantly associated with basic malaria understanding, basic malaria knowledge and malaria awareness. The basic malaria knowledge of participants living in the low MES was almost four times higher than that in the high MES (AOR: 3.75; 95% (CI): 2.75–5.11). Rural adults residing in the low MES were associated with a 241% higher prevalence of malaria awareness compared to rural adults in high MES (AOR: 2.41; 95% CI: 1.81–3.21). Malaria awareness of adults with diploma or above education level was seven times higher compared with those no education level (AOR: 7.08; 95% CI: 3.87–12.9 as shown in Fig 3.

Fig 3

The strength of association between malaria awareness and three types of malaria-endemic settings (MESs) in the East Nusa Tenggara Province, Indonesia.

Discussion

This is the first population-based study focusing on the malaria awareness of rural adults in three MESs in the ENTP since the Indonesian government launched its national commitment to eliminate malaria by 2030. The main finding of the study was that the malaria awareness of rural adults was very low, which presents a significant barrier to malaria elimination in the region. The results indicated that the malaria awareness of rural adults in the high MES was the lowest of all the MESs and education level was the prominent factors associated with this low level of malaria awareness.

This study showed that a high proportion of rural adults in high and moderate MESs had poor malaria knowledge. This finding was consistent with another study in Southern Africa [45], which revealed that residents in high MESs had lower malaria knowledge compared with those in low MESs. However, this finding contrasted with studies in China [36], Bangladesh [20], Eritrea [46], North Sudan [47], and India [48], which indicated that rural populations in high MESs had high malaria knowledge. This discrepancy might be explained by the fact that the rural communities in these countries had been exposed to various interventions to improve their malaria knowledge [20, 36, 37, 46, 47, 49]; additionally, in China, the government has included the malaria awareness index as one of the action plans for malaria elimination since 2010 [50]. However, in the ENTP the interventions to improve the malaria awareness of rural communities have not yet been documented. The findings of this study indicate that more attention should be paid to rural adults in high and moderate MESs to accelerate malaria elimination. However, considerable attention should be paid to rural adults in low MESs considering that high numbers of inter-province migration flow [51] and inter-district migration flow [52] could lead to imported malaria cases in this province.

The association between education level and malaria awareness of rural adults in this study appeared to corroborate with finding in other countries such as India [48], Bangladesh [53], and Malawi [54], revealing that a higher level of education was significantly associated with a high level of malaria awareness. In this study, malaria awareness of participants with at least a diploma level education was seven times higher than those with no education. Greater understanding is more likely that educated people tend to be exposed to multiple sources of information with higher health literacy [55]. They can understand an abstract concept on written information [56], allowing them to recognize various aspects of malaria. This study has shown that the proportion of rural adults having a primary education level or no education level is high (64.1%), well above the national population level (38.5%) [57]. Poorer education levels is associated with worse knowledge of malaria and needs more attention to address this disadvantage and improve health literacy on this topic in the region.

The findings of this study also indicated that the basic malaria knowledge of rural adults was very low. Only about 38% of rural adults could identify fever as the main symptom of malaria, meaning that more than half of rural adults could not correctly identify the main symptom of the disease. This could lead to low levels of awareness for malaria infection. This result contrasted with the findings of studies conducted in Cabo Verde [38], a region that is on track to achieve malaria elimination zone status by 2020 [2], and Iran [39], all of which indicated that a high proportion of participants could identify fever as the main symptom of malaria. Regarding the transmission mode of malaria, more than half of rural adults knew that malaria was caused by mosquito bite. However, this proportion was lower than that reported in other countries [38, 39, 46, 48, 58], which revealed that although most rural communities recognise mosquito bites as the main cause of malaria, there was still a large proportion of rural adults in the ENTP that lacked awareness of the need to protect against mosquito bites. A failure to improve the awareness of this community would lead to low levels of usage of the malaria prevention methods promoted by the Indonesian Government and, as a result, increase the burden of malaria in this province.

Four malaria prevention measures are available to rural adults in the ENTP, including sleeping under non-LLINs, using mosquito coils, keeping houses clean, and sleeping under LLINs. However, the proportion of participants that knew of these methods was very low and disparity amongst MESs for this knowledge was marked. It is worth noting that the percentage of rural adults with knowledge of at least one prevention measure was high, whereas the proportion of rural adults with knowledge of at least two prevention methods was significantly low. Combining various methods to prevent malaria is more effective than taking only one approach [59].

In this study, the proportion of rural adults with knowledge of sleeping under LLINs to prevent malaria was low. This finding contrasted with studies in other countries such as Tanzania [60], Eritrea [46], North Sudan [47], Iran [61], Bangladesh [53], and Southern Africa [45], which revealed that a high proportion of the rural community knew that sleeping under treated nets was a protective method to prevent malaria. This disparity may have been because of the different levels of knowledge about the transmission mode of malaria, as most of the rural populations in these countries could correctly identify the main cause of malaria, while in the ENTP only about half of the studied population knew that malaria was caused by mosquito bite. A failure to improve the awareness of communities about the benefits of sleeping under LLINs will have a negative impact on the malaria elimination program. A systematic review on the use of LLINs indicated that—despite LLINs being provided free of charge and supported by government agencies and many non-government organisations—a lack of awareness among communities has led to their misuse of LLINs, such as for the protecting and storage of food materials [62].

This study revealed that there was a significant difference regarding knowledge of sleeping under LLINs amongst the three different MESs. The highest percentage of rural adults with this knowledge was in the high MES, followed by the moderate MES, and the lowest was in the low MES. This finding was consistent with studies in Bangladesh [20] and Colombia [63]. The higher level of this knowledge in the high MES might have been due to the long-term exposure to the LLINs distribution program in this region. It is understood that in malaria-endemic communities with many ongoing malaria intervention programs, the level of malaria prevention knowledge should be higher compared to other areas in which there are fewer malaria prevention programs. Since 2008, there was greater targeting of the LLIN distribution program in the East Sumba district compared with other districts [13], and in 2017 during the mass LLIN campaign in the country, East Sumba was again included in the program [14].

Regarding perceptions of treatment-seeking behaviour, this study found that the awareness of the need to seek treatment within 24 hours when participants or their family members suffered from malaria was poor. This was consistent with other studies in some parts of Indonesia [22, 64], and other South-East Asian countries such as Myanmar [19], India [65], Bangladesh [53], and Cambodia [66]. The poor level of malaria treatment-seeking in this study may have been because over one-third of the total participants believed that malaria was not dangerous to their health; therefore, they treated malaria at home first for several days before they visited a local health centre. However, prompt treatment-seeking behaviour is critical to progress malaria elimination. Considering this low awareness amongst rural adults in the ENTP, more efforts are needed to improve awareness since failure to seek treatment within 24 hours after the onset of the clinical symptoms leads to an increased fatality rate [67].

Community engagement is fundamental to malaria elimination [68]. To improve engagement, community awareness should be measurable. The study indicated that the malaria awareness of participants was poor and that the malaria awareness index is not currently part of the malaria elimination program of the ENTP [69]. Therefore, the malaria awareness index should be included as a key strategic intervention of the ENTP to improve and measure the malaria awareness of the community: inclusion of this index would enable the local authority to implement interventions and evaluate the progress of malaria awareness of the local community at district, sub-district and village levels. Furthermore, improved awareness of infectious disease, including malaria, would enable the community to improve their self-protection behaviors and seek early treatment [70], find their preferred treatment source [71], and ultimately reduce the prevalence of malaria [20] towards eventual malaria elimination [72].

It is suggested that a partnership between the health and education departments of the ENTP could play a role in promoting malaria knowledge through the local curriculum, to improve the malaria awareness index of local communities. Students could be an important agent for change. They could be encouraged to share their malaria knowledge with their family, as has been demonstrated in other countries [73, 74]. The great achievement of the Chinese government to achieve zero local malaria transmission for the first time in 2017 was supported by a massive effort to improve the malaria awareness of communities, including school children [75]. Considering that a high proportion of residents in rural areas in the ENTP have no education [10, 76], a malaria education program in countryside schools could improve the malaria awareness of rural communities.

This research provides the first reliable data on malaria awareness and knowledge in the general population in Indonesia’s ENTP, particularly adults living in remote areas. The obtained dataset represents a large and representative sample size for this population. However, the potential weakness of this study was that data collection was during only one period and from only one province. This study needs to be repeated via random samples from other regions, enabling a truly representative national sample of rural adults to be captured. Additionally, because of the limited resources for this study, the inter- or intra-interviewer reliability could not be checked. The interviewers did not have a chance to interview the same research participants, so inter-intra reliability could not be evaluated. However, interviewers had a certified nursing degree and participated in one day of intensive training on applying a consistent interview approach. Despite these limitations, the findings of this study provide insights into the level of malaria understanding, knowledge and awareness of rural adults of the ENTP.

Conclusions

Malaria awareness of rural adults needs to be improved. Local government public health programs should incorporate a malaria awareness index as a key intervention and this should be measurable by setting up reasonable targets to improve the awareness of local communities. Having this index in the malaria elimination programs of the ENTP will help local authorities to manage and evaluate the progress of malaria awareness in the local community at the district, sub-district and village levels. Public health campaigns should focus on improving the basic malaria knowledge of rural adults in the province, such as the main symptom and transmission mode of malaria, malaria prevention methods, and the importance of seeking early treatment. This method will support the national action plan for malaria elimination in Indonesia. A failure to address malaria awareness in rural communities will mean that elimination will never be achieved.

(DOC)

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Database for study malaria awareness in East Nusa Tenggara Province Indonesia.

(PDF)

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17 Mar 2021

PONE-D-20-34159

Malaria awareness of adults in high, moderate and low transmission settings: A cross-sectional study in rural East Nusa Tenggara Province, Indonesia

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Reviewer #1: In the introduction section, the author should mention and analyze several strategies that have been conducted in the ENTP to eliminate malaria. This explanation would give a more substantial argument why study regarding malaria knowledge related to the symptom, transmission mode, prevention method, and the perception of malaria treatment-seeking behavior in the population-level study, thus important.

Reviewer #2: abstract

Materials and methods

study population, sample size and sampling method were not indicated.

strong model like logistic regression is preferable to chi square

Results

The proportion of malaria awareness index should be specified along with CI.

Main body

Introduction

Research gap was not indicated

Materials and methods

Sample size was not determined.

data collection method was specified

malaria awareness assessment was not clear.

confidentiality issue and privacy was stated.

Results

The proportion of malaria awareness index should be specified along with CI.

The findings were not written in logical order

Discussions

The findings were not well written.

The findings have not been contrasted.

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1 May 2021

REBUTTAL LETTER

PONE-D-20-34159

Malaria awareness of adults in high, moderate and low transmission settings: A cross-sectional study in rural East Nusa Tenggara Province, Indonesia

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Response:

Thank you for this feedback. We have updated the manuscript to meet the PLOS ONE style requirements including file naming.

2. Please include a copy of the questionnaire in the original language as Supporting Information or include a citation if it has been published previously.

Response:

The original language of the questionnaire is a part of published protocol paper. We have cited this protocol paper in our manuscript as reference number 33.

3. In the Methods, please discuss whether and how the questionnaire was validated and/or pre-tested. If these did not occur, please provide the rationale for not doing so.

Response:

Thank you for this recommendation. The questionnaire used for this study has been adapted from a validated questionnaire which was published previously (reference numbers 35 and 36). The questionnaire was translated into local language and we also conducted a pre-test upon 30 participants before finalising the questionnaire. This is now explained in the data collection section under material and methods (page 8 line 2 – 13).

4. In your statistical analyses, please state whether you accounted for clustering by region. For example, did you consider using multilevel models?

Response:

In this study, we want to develop malaria awareness of rural ENTP and evaluate the association between malaria awareness and three malaria endemic settings (MES). Since the main question for this study is whether any a significant association between malaria awareness having binary response and different types of MES, we believe the logistic regression method is suitable for this research question. Furthermore, we do not want to predict malaria awareness amongst three different MES based on their characteristics, therefore we did not use multilevel models for this study. Reporting the malaria awareness as a whole was not our objective.

5. Please include your tables as part of your main manuscript and remove the individual files. Please note that supplementary tables should remain uploaded as separate "supporting information" files.

Response:

We have now included Table 1 and Table 2 in this manuscript. However, the size of Table 3 was big. Following the guideline of PLOS One Journal, if the size of table was not fitted in the manuscript due to the its size, it can be transformed to figure and uploaded as separate file. Therefore, we uploaded Table 3 as a figure in a different file.

6. We note that you have stated that you will provide repository information for your data at acceptance. Should your manuscript be accepted for publication, we will hold it until you provide the relevant accession numbers or DOIs necessary to access your data. If you wish to make changes to your Data Availability statement, please describe these changes in your cover letter and we will update your Data Availability statement to reflect the information you provide.

Response:

We have attached our database in this manuscript to support our findings as supporting information in this submission as shown in page 23 line 24.

7. We note that Figure 1 in your submission contain map images which may be copyrighted. All PLOS content is published under the Creative Commons Attribution License (CC BY 4.0), which means that the manuscript, images, and Supporting Information files will be freely available online, and any third party is permitted to access, download, copy, distribute, and use these materials in any way, even commercially, with proper attribution. For these reasons, we cannot publish previously copyrighted maps or satellite images created using proprietary data, such as Google software (Google Maps, Street View, and Earth).

We require you to either (1) present written permission from the copyright holder to publish these figures specifically under the CC BY 4.0 license, or (2) remove the figures from your submission:

Response:

Thank you the academic editor for this recommendation. We have updated the figure 1 for the location of the study. The map was developed by the author of this article. We developed map using ggplot2 and map package in R software version 3.5.3

8. Please include captions for your Supporting Information files at the end of your manuscript, and update any in-text citations to match accordingly. Please see our Supporting Information guidelines for more information: http://journals.plos.org/plosone/s/supporting-information.

Response:

We have added in-text citations for this supporting information as indicated in page 6 line 23, page 16 line 9, and page 17 line 10. The caption for the supporting information files has been also added at the end of our manuscript as shown in page 23 line 19 and 24.

Reviewer's Responses to Questions

5. Review Comments to the Author

Reviewer #1: In the introduction section, the author should mention and analyze several strategies that have been conducted in the ENTP to eliminate malaria. This explanation would give a more substantial argument why study regarding malaria knowledge related to the symptom, transmission mode, prevention method, and the perception of malaria treatment-seeking behavior in the population-level study, thus important.

Response:

We have updated the introduction section of the manuscript. We have presented some intervention methods that have been implemented in the ENTP as a part of the effort of the local government to eliminate malaria by 2030. However, their intervention might be ineffective since the number of malaria cases is still high and their intervention might be dependent on the knowledge and behaviour of the local community which is limited investigated in the study area as indicated in page 4 from line 11 to 25 and page 5 from line 1 to 4. We have also shown the gap between previous malaria studies on malaria knowledge in the ENTP and the current study that we have conducted in order to provide the best solution for malaria elimination program in the ENTP as shown in page 5 from line 18 to 25 and page 6 from line 1 to 11.

Reviewer #2: abstract

Materials and methods

study population, sample size and sampling method were not indicated.

Response:

We have updated the material and methods section in the abstract. The information on the study population, sample size and sampling method has been added in the abstract as indicated page 2 from line 8 to 11.

Strong model like logistic regression is preferable to chi square

Response:

Thank you to the reviewer #2 for this suggestion. The purpose of this article is to develop malaria awareness index and to evaluate the association of the malaria awareness index amongst community in three different malaria endemic settings of rural adults in ENTP Indonesia. The outcome variables is proportion of rural adults having malaria awareness in each different types of malaria endemic settings. Firstly, we show the association between malaria endemic settings and basic malaria understanding, basic malaria knowledge, as well as malaria awareness applying chi-square test. Furthermore using odds ratio in logistic regression model, we have shown that there is a significant association between malaria endemic settings and basic malaria understanding, basic malaria knowledge, as well as malaria awareness. This information has been updated in the article as shown in page 2 line 12 and 13, page 10 line 19 to 25 and page 11 from line 1 to 3.

Results

The proportion of malaria awareness index should be specified along with CI.

Response:

Thank you to the review #2 for this recommendation. We have updated the result section of the abstract. The proportion of malaria awareness index has been specified along with 95% confidence interval as indicated in page 2 from line 16 to 25 and page 3 line 1.

Main body

Introduction

Research gap was not indicated

Response:

Thank you to the reviewer #2 to this recommendation. We have updated the manuscript. We have updated 2 paragraphs in the manuscript to indicate the research gap in our paper. For the first paragraph, as indicated in page 4 from line 11 to 25 and page 5 from line 1 to 4 of the manuscript, we have presented some evidence of interventions conducted by local authority and independent researchers as a part of their effort to eliminate malaria in line with the national commitment of the country. Most of their intervention might be ineffective since the number of malaria cases still high in the province and the implementation of their intervention might depend on the community behaviour which is limited investigated in the study area. So this is the main reason for conducting this study.

For the second paragraph of the research gap, as indicated in page 5 from line 18 to 25 and page 6 from line 1 to 11 of the manuscript, we have updated the article with the new evidence on malaria awareness research in the ENTP indicating low awareness of community in malaria prevention method using the long-lasting insecticide- treated nets (LLINs), however their study evaluated only awareness of pregnant women on malaria prevention method living in high malaria endemic settings (MES). Therefore, their study cannot compare the malaria awareness amongst other types of MES in the ENTP. In our study, we develop malaria awareness of rural adults in ENTP and investigate the difference of malaria awareness amongst different types of MES. These findings allow us to provide new evidence which MES should be prioritized and which aspect should be focus in providing key intervention for rural community in the effort to progress to malaria elimination by 2030. Therefore, our study will provide the novelty of malaria awareness of rural ENTP and the comparison of malaria awareness amongst MES in the ENTP.

Materials and methods

Sample size was not determined.

Response:

Thank you to the reviewer #2 for this suggestion. We have updated the article. Overall procedure on how to calculate the sample size has been added in the article. We determined our sample size taking into account of malaria prevalence study previously, design effect, cluster size, and participation rate of the participants in East Nusa Tenggara Province Indonesia. The comprehensive information on the calculation of sample size has been published in our prior publication as indicated in the reference number 33 of this manuscript. All this information were presented in page 7 from line 3 to 11.

Data collection method was specified

Response:

We have updated the article and data collection method has been added in this manuscript. For this study we applied face-to-face interview guided by the validated questionnaire as indicated in page 8 from line 3 to 13.

Malaria awareness assessment was not clear.

Response:

Thank you to the reviewer #2 for this recommendation. We have updated the article. We have presented ten questions used to evaluate malaria awareness of participants. The first three questions categorized as basic understanding of malaria including whether participants have heard malaria term, whether malaria was dangerous for their health, whether malaria can be prevented. The next seven questions categorized as basic malaria knowledge comprising whether participants could identify the main symptom and the main cause of malaria, whether participants could identify some protective measure to prevent malaria, whether participants seeking treatment for their malaria within 24 hours after the onset of the symptoms. Participants who could identify fever as the main symptom of malaria and mosquito bites as the main cause of malaria obtained score one respectively. Participants who could mention sleeping under non-LLINs, sleeping under LLINs, using mosquito coils, keeping house clean as the method to prevent malaria got score one respectively. Finally, participants who mention seeking malaria treatment within 24 hours for their malaria obtained score one.

Overall, each participants get a total score of ten if they could answer correctly all these questions. Total marks of ten questions were evaluated following the previous malaria awareness studies as indicated in the reference number 37 and 38. Participants answering correctly at least 60% for these ten questions were categorized as having malaria awareness. The classification of participants to be categorized as aware or unaware of basic malaria understanding and basic malaria knowledge was also following the guidance of previous study (reference number 37 and 38). All this explanation have been updated in the article as shown in page 8 from line 16 to 24 and page 9 from line 1 to 22.

.

Confidentiality issue and privacy was stated.

Response:

In the ethic approval section of this article, we have presented that this study has been approved by ethics committee of Swinburne University of Technology and Health Ministry of Indonesia government where we extensively addressed how we would address issues around confidentiality. The confidential issue and privacy of participants has also followed the procedure in the tenet of The Declaration of Helsinki as indicated in page 11 from line 6 to 16 in the manuscript. The evidence of ethics approval from Swinburne University of Technology and Health Ministry of Indonesia government has been uploaded to the system.

Results

The proportion of malaria awareness index should be specified along with CI.

Response:

Thank you to the reviewer #2 for this recommendation. We have updated the article and 95% of confidence interval of the proportion of malaria awareness index has been calculated and added in this manuscript as indicated in page 13 from line 10 to 19 and from page 14 to 17. The proportion of malaria awareness index in Table 2 has been also supported with 95% confidence interval as indicated in page 15.

The findings were not written in logical order

Response:

Thank you to the reviewer #2 for this recommendation. We have updated the article. We arranged to present our findings into four themes including demographic characteristic of respondents, malaria knowledge of participants, malaria awareness of participants, the strength of the association between malaria awareness and malaria endemic settings (MES). In each theme, we compared the interest point amongst MES.

The demographic characteristic of participant was presented in page 11 from line 20 to 24 and page 12 from line 1 to 3. Malaria knowledge of participants was divided into basic malaria understanding as indicated in page 13 from line 7 to line 13, and the basic malaria knowledge as shown in page 15 from line 19 to line 16 and page 14 from line 1 to 2. Knowledge on malaria prevention methods was presented in page 14 from line 4 to 15, and the understanding of treatment seeking behaviour was shown in page 14 from line 17 to 22. In each section, we made comparison of understanding amongst three different malaria endemic settings.

The main result, malaria awareness index of participants was presented at page 16. In this part, we started with the awareness of basic malaria understanding and basic malaria knowledge as indicated in page 16 from line 14 to 22. Next, we presented malaria awareness index of participants as shown in page 16 from line 24 to 25 and page 17 from line 1 to 4. In each part, the comparison of malaria awareness amongst three different types of malaria endemic settings has been provided.

Finally, at the last part of the result section, we presented the strength of association between malaria awareness index and MES as shown in page 17 from line 10 to 18.

Discussions

The findings were not well written.

Response:

Thank you to the reviewer #2 for this recommendation. We have improved the manuscript. Firstly, we present our main findings which are the low level of malaria awareness amongst rural community in the ENTP and the high MES has the lowest malaria awareness as indicated in page 17 from line 21 to 24 and page 18 from line 1 to 2.

Then we compare our main findings with other countries and we provided explanation on why there is a significant discrepancy in malaria awareness in ENTP Indonesia and other countries that had implemented malaria intervention to improve malaria knowledge of the rural community as indicated in page18 from line 2 to 18.

The next part is presenting the discussion on malaria awareness in more detail started from basic malaria knowledge on main symptom and main causes as indicated in page 18 from line 20 to 25 and page 19 from line 1 to 9. The discussion on the awareness on sleeping under LLINs to prevent malaria and the comparison with other countries as well as the reason for the difference in ENTP and other countries has been presented in page 19 from line 1 to 25 and page 20 from line 1 to 7.

The discussion on awareness on malaria prevention method and the possibility reason why there is a discrepancy in this awareness between MES in ENTP was provided in the page 20 from line 9 to 19.

Regarding to malaria treatment seeking behaviour and the discussion of why the level of this awareness was low, it is presented in page 20 from line 21 to 25 and page 21 from line 1 to 6.

The next part we provided some recommendations to support malaria elimination program in the ENTP as indicated in page 21 from line 8 to 25 and page 22 from line 1 to 4.

Finally the strength and limitation of the research has been presented at the end of the discussion as indicated in page 22 from line 6 to 17.

The findings have not been contrasted.

Response:

Thank you to the reviewer #2 for this recommendation. We have improved the manuscript. We have compared our findings with malaria studies in other countries. The main findings of the study was the low level of malaria awareness of rural population and the lowest malaria awareness was in high Malaria endemic setting (MES) in ENTP Indonesia. This finding has been compared with 6 studies in different countries and we provided an argument to explain the possibility reason for the discrepancy of malaria awareness between ENTP Indonesia and other countries as shown in page 18 from line 4 to 18.

The awareness of various aspects of malaria has been also compared with another countries. The awareness of basic malaria knowledge on main malaria symptom has been compared with 2 studies in different countries as indicated in page 18 from line 20 to 25. The awareness on the main causes of malaria has been compared with similar study in 5 countries as shown in page 19 from 1 to 9.

The awareness of sleeping under LLINs to prevent malaria has been also compared with similar studies in 6 countries. The possibility reason for the disparity of this awareness in ENTP Indonesia and other countries has been also provided as indicated in page 19 from line 20 to 25 and page 20 from line 1 to 7. Meanwhile, for the difference in the awareness of sleeping under LLINs amongst MES in ENTP has been compared with similar studies in 2 countries. The possibility reason for the trend has also been supported as indicated in page 20 from line 9 to 19.

Finally, the awareness of treatment seeking behaviour of rural population ENTP Indonesia has been compared with similar studies in 2 other provinces of Indonesia and in 4 countries in Asia. The discussion on this low awareness has been also provided as indicated in page 20 from line 21 to 25 and page 21 from line 1 to 6.

Submitted filename: Response to Reviewers.docx

Click here for additional data file.

25 May 2021

PONE-D-20-34159R1

Malaria awareness of adults in high, moderate and low transmission settings: A cross-sectional study in rural East Nusa Tenggara Province, Indonesia

PLOS ONE

Dear Author,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please submit your revised manuscript by Jul 09 2021 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

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If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

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We look forward to receiving your revised manuscript.

Kind regards,

Ramesh Kumar, PhD

Academic Editor

PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: (No Response)

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: No

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: No

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Dear Author,

I appreciate your hard work improving this paper and appreciate your responsiveness.

Your response to my comments and your revision according to the comments are acceptable.

You did a good job.

Good luck.

Reviewer #2: Major assumptions of logistics regression analysis like Multi collinearity not stated. Model fitness test was not indicated. What was outcome measure? What is the type of test? The results of logistics regression analyses were not presented.

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

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Reviewer #1: No

Reviewer #2: No

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10 Jun 2021

REBUTTAL LETTER

PONE-D-20-34159R1

“Malaria awareness of adults in high, moderate and low transmission settings: A cross-sectional study in rural East Nusa Tenggara Province, Indonesia”

PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

Response:

Thank you for this feedback. We have updated the reference list. Since the Indonesian government has released the current number of malaria cases in Indonesia, we have changed the reference [8] to the year 2020. We have updated all this information as indicated on page 4 in the manuscript. All other references have been prepared following the guidance of the journal.

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: (No Response)

Response:

Thank you for your comments

________________________________________

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

Response:

Thank you for your comments

________________________________________

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

Response:

Thank you for your comments

________________________________________

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: No

Response:

All data underlying the findings of this manuscript has been made available as a part of supporting information of this manuscript.

________________________________________

5. Is the manuscript presented in an intelligible fashion and written in Standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: No

Response:

We have sought the assistance of a professional editor to review our paper to address these concerns (a certificate is attached). All authors have spent considerable time editing this paper.

________________________________________

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Dear Author,

I appreciate your hard work improving this paper and appreciate your responsiveness.

Your response to my comments and your revision according to the comments are acceptable.

You did a good job.

Good luck.

Reviewer #2: Major assumptions of logistics regression analysis like Multi collinearity not stated. Model fitness test was not indicated. What was outcome measure? What is the type of test? The results of logistics regression analyses were not presented.

Response:

Thank you to the reviewer #2 to this recommendation.

For the assumption of multi-collinearity, since there is a significant correlation between education level and socio-economic status (SES), we removed the SES variable from the logistic regression model for covariate adjustment. With or without SES also did not change the Wald statistics significantly. Therefore, the final odds ratio was obtained after adjusted for gender, age group and education level.

There are three outcome measures of the study. They are basic malaria understanding (the first outcome), basic malaria knowledge (the second outcome), and malaria awareness (the third outcome). All these outcomes were binary variables as indicated on page 8 from line 2 to 25 and page 9 from line 1 to 7.

The overall model fit test was evaluated by the omnibus chi-square test and classification tables. The value of the omnibus chi-square test was significant for all outcomes of the study (p-value < 0.001). This indicates an association between outcome variables and malaria-endemic settings. The classification tables also indicate the significant results for three outcomes. The classification accuracy for the first, second and third outcomes was 83.6%, 69.4%, and 66.3%, respectively.

For the type of test, the significance of the individual variable was evaluated by Wald statistics. All Wald statistics for three outcomes show a significant result (p-value < 0.001).

The results of logistic regression have been presented in figure 3, as indicated on page 16 of the manuscript.

Submitted filename: Response to Reviewers.docx

Click here for additional data file.

26 Jul 2021

PONE-D-20-34159R2

Malaria awareness of adults in high, moderate and low transmission settings: A cross-sectional study in rural East Nusa Tenggara Province, Indonesia

PLOS ONE

Dear Author,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please revise your paper as per the comments provided with this email.

Please submit your revised manuscript by Sep 09 2021 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.

A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.

An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols.

We look forward to receiving your revised manuscript.

Kind regards,

Ramesh Kumar, PhD

Academic Editor

PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #2: (No Response)

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #2: No

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #2: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #2: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #2: No

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #2: Abstract

The authors did not write their manuscript rigorously.

The following concerns should be addressed.

types of study, data collection technique, and types of logistic regression analysis were not specified

Main body

Material and methods

There was major methodological defect:

types of study, Source population, study population, inclusion criteria and exclusion criteria were not stated

Sample size determination was not succinctly computed.

Design effect was not considered.

Sampling technique was not clearly stated

Data collection technique,

Descriptive statistics, and types of logistic regression analysis were not specified, model assumptions (multicollinearity) was not checked and its value was not indicated. Was there interaction?

How did you estimate strength of association b/n explanatory variables and endpoint?

What are the strategies to CONTROL CONFOUNDERS?

How did you identify model fitness?

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #2: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

17 Aug 2021

REBUTTAL LETTER

PONE-D-20-34159R2

Malaria awareness of adults in high, moderate and low transmission settings: A cross-sectional study in rural East Nusa Tenggara Province, Indonesia

PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

Response:

Thank you for this feedback. We have updated the reference list. We added reference [31] to support the sample size calculation, reference [43] for controlling confounding factors, and reference [53], [54], [55], [56] to support the argument for the association between malaria awareness and education level in the discussion section. All references have been prepared following the guidance of the journal.

Reviewers' comments:

Reviewer #2: Abstract

The authors did not write their manuscript rigorously.

The following concerns should be addressed:

1. Types of study, data collection technique, and types of logistic regression analysis were not specified.

Response:

We have updated methods section in the abstract as:

“A community-based cross-sectional study was conducted between October and December 2019 in high, moderate, and low malaria-endemic settings (MESs) in the ENTP. After obtaining informed consent, data were collected using an interviewer-administered structure questionnaire among 1503 participants recruited by a multi-stage cluster sampling method. A malaria awareness index was developed based on ten questions. A binary logistic regression method was applied to investigate the significance of any association between malaria awareness and the different MESs” (page 2, lines 8 -14).

Main body

Material and methods

There was major methodological defect:

1. types of study, Source population, study population, inclusion criteria and exclusion criteria were not stated

Response:

We have updated the material and method section. The study site is updated by including

“This community-based cross-sectional study was conducted from October to December 2019 in three districts out of 21 districts and one municipality in the province. They were East Sumba, Belu, and East Manggarai districts representing high, moderate, and low MESs, respectively” (page 6, lines 17-20).

The sampling technique section is updated by including

“All adults in ENTP were the source population, and all adults in the selected three districts were the study population” (page 7, lines 14 -15).

“In each selected household, one head of the family of any gender who provided consent to participate voluntarily was included in the study. If the household head, either husband or wife, was absent, residents over 18 years of age could serve as study participants [33]. We excluded anyone under the age of 18 years old from the study” (page 7, lines 22 - 25).

2. Sample size determination was not succinctly computed.

Design effect was not considered.

Response:

Thank you for this feedback. We have updated the sample size determination section as below:

“The initial sample size (n0) was calculated based on the formula n0 = Z2P(1-P)/d2 for the prevalence study of a cross-sectional study [31]. The parameters Z is the value of standard score of 95% confidence interval (1.96), P is the prevalence of malaria study in the ENTP conducted by the Indonesian government (1.99%) [9] , and d is the relative precision which is 0.01125. Therefore, the initial sample size n0 was equal to 592. The design effect was accounted for due to cluster sampling by the multiplication of a factor of 2.16. By considering the participation rate of 85%, the final sample size was 1503 adults. The sample size calculation was described previously [32]” (page 7, lines 3-10).

3. Sampling technique was not clearly stated

Response:

Thank you for this feedback. We have updated the sampling technique section as below:

“A multi-stage cluster sampling procedure with a systematic random sampling procedure at the final cluster level was applied to recruit adults from the three districts. At cluster level 1, three districts were selected out of 22 in the ENTP based on the annual parasite incidence (API) of malaria, at cluster level 2, three sub-districts were randomly chosen from each selected district. At cluster level 3, the number of villages selected from each sub-district was based on their relative populations. At the final cluster level, a systematic random sampling technique was used to recruit 20–40 participants per village, proportionate to the population size of each village” (page 7, lines 15 – 22).

4. Data collection technique

Response:

Thank you for this feedback. We have improved data collection technique section by including the following information:

“An interviewer-administered questionnaire adapted from a validated questionnaire [34, 35] was used to collect data for this study. The English version of the questionnaire was translated into the local language by the lead author of this article and a local language expert. They then combined the two translated versions. The combined version of the questionnaire was then tested on 30 participants before finalization. The data were collected in collaboration with local nurses who were residents in the study area. Nine local nurses, three nurses from each district conducted face-to-face interviews with participants based on the guidance of the structured questionnaire. The data collection process was monitored strictly by the investigator daily to check the questionnaire's completeness. Data on the socio-demographic variables and general knowledge of malaria was collected during the interview” (page 8, lines 2 – 11).

5. Descriptive statistics, and types of logistic regression analysis were not specified, model assumptions (multicollinearity) was not checked and its value was not indicated. Was there interaction?

Response:

Thank you for this feedback. The descriptive statistics has been specified in the statistical analysis section as:

“The proportion of participants answering each question correctly and its 95% confidence interval (CI) were computed for each MES” (page 10, lines 17-19).

Types of logistic regression, adjustment and addressing the issue of multicollinearity have been presented in Statistical analysis section as:

“A univariate and multivariate binary logistic regression model was applied to evaluate the association between the dependent and the independent variables. The associations were reported as odds ratio with its 95% CI. Multicollinearity tests amongst the independent variables were done before multivariate analysis was conducted” (page 10, lines 22 – 25 and page 11 line 1).

6. How did you estimate strength of association b/n explanatory variables and endpoint?

Response:

Thank you for this feedback. The strength of association between explanatory variables and endpoint has been specified in the statistical analysis section as:

“The direction and strength of association between explanatory variables and endpoints were estimated by adjusting the odds ratio” (page 11, lines 7 – 8).

7. What are the strategies to CONTROL CONFOUNDERS?

Response:

Thank you for this feedback. Strategies to control confounders have been specified in the statistical analysis section as:

“In the univariate binary logistic regression, all variables having a p-value < 0.10 were included in the multivariate analysis to control confounding factors [43]” (page 11, lines 3 – 5).

8. How did you identify model fitness?

Response:

Thank you for this feedback. The model fitness test has been specified in the statistical analysis section as:

“The Hosman and Lemeshow test evaluated the overall model fitness with a significance level of p < 0.05” (page 11, lines 1-2).

Submitted filename: Response to Reviewers.docx

Click here for additional data file.

2 Nov 2021

Malaria awareness of adults in high, moderate and low transmission settings: A cross-sectional study in rural East Nusa Tenggara Province, Indonesia

PONE-D-20-34159R3

Dear Author,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Ramesh Kumar, PhD

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #2: All comments have been addressed

Reviewer #3: All comments have been addressed

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #2: Yes

Reviewer #3: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #2: (No Response)

Reviewer #3: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

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Reviewer #2: Yes

Reviewer #3: Yes

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

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Reviewer #2: Yes

Reviewer #3: Yes

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6. Review Comments to the Author

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Reviewer #2: The authors should write their manuscript rigorously,

The language editorial problems should be corrected to enrich their work.

The sampling technique should be written succinctly

Reviewer #3: (No Response)

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Reviewer #2: No

Reviewer #3: Yes: Midhat Farzeen

4 Nov 2021

PONE-D-20-34159R3

Malaria awareness of adults in high, moderate and low transmission settings: A cross-sectional study in rural East Nusa Tenggara Province, Indonesia

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