Primary care physicians' knowledge of travel vaccine and malaria chemoprophylaxis and associated predictors in Qatar.

BACKGROUND: In an era of globalization, travel-related illnesses have become a focus of public ‎health concern, especially in the Arab region where travel health services are insufficient and ‎not well-established. This study was conducted to assess travel vaccine and ‎malaria chemoprophylaxis knowledge and associated predictors among primary care physicians‎ (PCPs) in ‎Qatar.
METHODS: This was a cross-sectional study. A structured questionnaire was used to collect ‎data from all physicians working at all 27 primary healthcare centers from March 1st to May 31st 2020.‎ Knowledge scores were computed and a multivariable linear regression model was built to identify predictors of higher knowledge.
RESULTS: A total of 364 PCPs participated (response rate of 89.2%). Participants' mean ‎age was 44.5 (±7.8) with 59.1% being males. Their overall mean knowledge score was 9.54/16 (±3.24). Significant predictors of higher knowledge included: aged 40-49 years ‎(1.072; 95% CI: 0.230, 1.915)‎, had medical degree from non-Arab countries ‏‎(0.748; 95% CI: 0.065, ‎‎1.432)‎‏,‏‎ had training in TM ‏ ‏‎(1.405; 95% CI: 0.407, ‎‎2.403), and provided ≥10 consultations/ month ‎(2.585; 95% CI:1.294, 3.876)‎. Online information was the main reported resource of travel medicine consultation.
CONCLUSIONS: The overall PCPs' mean percentage knowledge score of travel medicine was 59.6% (±20.3). A high volume of pretravel consultation, prior training, middle age group, and medical degree from non-Arab countries were significant predictors of higher ‎knowledge. Continuing ‎education and training provided by recognised international institutions for all PCPs is highly ‎recommended to narrow the gap in travel medicine knowledge.

Introduction

Travel medicine (TM) is an emerging and fast-growing discipline that is concerned with the prevention and ‎management of travel-related health problems [1]. International travel has substantially increased over the past few decades with international tourism growing by 4% in 2019 reaching 1.5 billion [2]. Qatar as well has witnessed an increase in outbound and inbound travellers with 1.8 million arrivals in 2018 [3]. Moreover, Qatar will be the host country for the 2022 FIFA (Fédération Internationale de Football Association) World Cup. Such a major international event will lead to a spike in arrivals including foreign workers, tourists, and others visiting friends and relatives ‎[4].

In an era of globalization, travel-related illnesses have become a focus of public health concern, particularly in many countries in the Arab region where primary health care is fragmented and travel health services are insufficient and ‎not well-established [5, 6]. A recent review estimated that between 43% and 79% of travellers who visited developing nations become ill [7]. Nevertheless, travellers from Qatar tend to visit high-risk destinations [8]. A main health concern in travellers is malaria, which remains a leading cause of morbidity and mortality worldwide [9].‎ A study in Qatar about the epidemiology of malaria showed that the incidence rate of imported malaria had increased from 15 to 19 cases per 100,000 from 2008 to 2015, respectively. The majority of the cases were imported from malaria-endemic countries such as India, Nepal, Pakistan, and Sudan and were reported mainly among adult male expatriates and those who visited relatives and friends‎ [10]. While malaria is legislatively reportable to the Ministry of Public Health in Qatar‎, no data are available for other travel-related illnesses.

Primary Care Physicians (PCPs) are usually the first line of contact for pretravel consultation. Because of their broad scope of training, particularly in prevention, and counselling skills, they are positioned to be the most suitable healthcare practitioners to practice TM in Qatar [11, 12]. PCPs should remain current about their knowledge of the dynamics of communicable diseases and other travel-related issues. Moreover, they need to have access to current evidence-based resources and guidelines as ‎well as ongoing training in TM [12].

Moreover, PCPs play a vital role in identifying at-risk travellers and highlighting the importance ‎of pretravel consultation [11, 13]. ‎Adequate pretravel consultation is crucial for travellers’ health. It aims to mitigate their risk of illness and injury during travel through preventive counselling, chemoprophylaxis, and vaccinations as needed [14, 15]. The outcome of a pretravel consultation depends on the extent of PCPs’ knowledge, experience, and communication skills [13, 14]. Therefore, PCPs should have the necessary knowledge to advise travellers on the most appropriate travel vaccines and malaria chemoprophylaxis to prevent adverse health outcomes during their travel [15].

Several worldwide studies on PCPs’ level of knowledge about TM have shown wide discrepancies in the findings. For instance, Alduraibi et al. (2020) in Saudi Arabia found a poor level of knowledge [16]. Another study conducted in Germany and Switzerland reported poor and moderate levels respectively [17], while a study in the United Kingdom reported a higher level of knowledge [18]. In addition, a previous study by Al-Hajri et al. in Qatar of a convenient sample of 76 PCPs assessed ‎their knowledge of TM before and after a symposium [19]. The study found an improvement in PCPs’ knowledge after the symposium. However, the study did not provide data on knowledge score before or after the symposium. In addition, the authors did not assess the predictors of PCPs’ ‎knowledge in relation to TM. Therefore, there is little current data available about their knowledge of TM. Hence, the objectives of this study were to examine PCPs’ knowledge related to travel vaccines and malaria chemoprophylaxis and their associated predictors, and resources they used for TM-related consultations.

Material and methods

Study design and setting

An analytical cross-sectional design was conducted at all 27 PHC centers in Qatar from March 1st to May 31st 2020. These PHC centers are situated in three administrative municipalities (Northern, Western and Southern) according to their respective population densities [20]. They are designed to be the first-line level of contact with Qatar’s healthcare system for the provision of comprehensive healthcare services including TM ‎[21]. Travel Medicine services including travel vaccines and malaria chemoprophylaxis, are mainly provided by non-‎specialized PCPs practicing in PHC centers, but do not cover comprehensive travel advice. The ‎services are provided free of charge for Qatari citizens and highly subsidized for non-Qatari ‎residents‎.

Study population

All available PCPs who provide clinical consultations were invited to participate in the study. The estimated sample size was 365 individuals based on 3% ‎absolute precision, 95% confidence, a hypothesis that 50% of PCPs have sufficient knowledge of TM, and a non-response rate of 20%. The calculation of sample size was performed to obtain a sufficiently precise estimate of the minimum number of study participants to ensure study power.

Data collection

Data collection was done using an anonymized, self-administered questionnaire, which is described below. All PCPs who were on duty during data collection were approached in person by the researcher (AAD) in their respective clinics. ‎The researcher gave a comprehensive orientation about the nature and purpose of the study and invited them to participate with an emphasis that their participation was voluntary.‎ Those who consented to participate were given a copy of the questionnaire. Also, ‎they were instructed to place the completed questionnaires in provided sealed and unmarked envelopes that were collected later by the researcher. ‎No incentives or compensation were offered to the participants.

Study questionnaire

A structured questionnaire was used for data collection S1 File. Face and content validity were determined by conducting an extensive search of the literature, and critical review by an expert ‎panel made up of TM experts and Community Medicine consultants. The questionnaire was in English as it is the main communication language of all physicians in Qatar. ‎ The questionnaire comprised three main sections. Section A consisted of 7 questions exploring the sociodemographic and practice-related characteristics of the participants (age, gender, country of medical degree‎, number of years in general practice, postgraduate experience in TM “defined as any engagement in travel medicine practice after graduation from medical school”, postgraduate training in TM “defined as receiving any postgraduate degree [Diploma, Master, PhD] or training [workshop, ‎certified short course] or having a membership or fellowship of TM related professional ‎organization‎", and frequency of pretravel consultations per month). Section B included 5 questions about information resources accessed for TM counselling. Section C included 16 close-ended questions to assess PCPs’ knowledge as follows: 12 questions related to travel vaccine recommendations and 4 questions related to malaria ‎chemoprophylaxis recommendations for selected destinations. These destinations were frequent holiday destinations of travellers from Qatar [4, 8]‎. Responses to the knowledge questions were assigned a score of one for each ‎correct answer and zero for each incorrect or “don’t know” answer. Therefore, the overall ‎knowledge scores computed could range from 0 to 16. The reliability of the knowledge scale was evaluated through Cronbach’s alpha. The result was a ‎coefficient of α = 0.839 which is considered good [22]. ‎The questionnaire was piloted with a convenient sample of 20 PCPs to assess its relevance, clarity, and average duration for its completion. The pilot sample was excluded from the final database.

Statistical analysis

The data were analysed using the IBM SPSS Statistics for Windows (version 23, IBM Corp., Armonk, N.Y., USA). Both descriptive and analytic statistics were applied. For descriptive statistics, frequencies (counts) and percentages were calculated for categorical variables while means and standard deviations (SD) were calculated for numeric variables. For analytical statistics, Student’s t-test and Analysis of Variance (ANOVA) were applied for numerical outcomes. The multivariable linear regression analysis was performed to identify predictors of TM knowledge. All factors tested in the bivariate analysis were included in the multivariable analysis. Missing data were dealt with through list-wise deletion.‎ We performed the Hosmer-Lemeshow goodness of fit test and its findings indicate that our ‎model adequately fits the data. Adjusted differences in means with their 95% CI and p-values were reported. Statistical significance was considered at p ≤ 0.05 as a cut-off point.

Ethical considerations

This study was approved by the Institutional Review Board of Hamad Medical Corporation [Reference No.: MRC-01-19-324] and Primary Health Care Corporation [Reference No.: PHCC/DCR/2020/01/002]. The questionnaire was anonymized and written consent was obtained from all participants before enrolment.

Results

Background characteristics of the study population

A total of 364 out of 408 invited PCPs participated in the study (response rate: 89.2%) with time constraints being the main reason for non-participation. Table 1 shows the background characteristics of participants. The mean age of the PCPs was 44.5 (SD ±7.8) years and 59.1% were male physicians. The most frequent country of medical degree was Egypt (22.9%) followed by the United Kingdom (19.7%). More than half of the PCPs (53.2%) had between 10–19 years in general practice and 15.1% had postgraduate training in TM. Almost two-thirds ‎(67.4%) provided less than 10 pretravel consultations per month.

Table 1

Distribution of background characteristics of primary care physicians in Qatar (N = 364).

Variable	Frequency	Percent
Age
<40 years old	93	27.0
40–49 years old	176	51.2
≥50 years old	75	21.8
Mean ±SD	‎44.5±7.8‎
Gender
Male	215	59.1
Female	149	40.9
Country of medical degree
Egypt	79	22.9
United Kingdom	68	19.7
Pakistan	63	18.3
India	23	6.7
Iraq	19	5.5
Sudan	17	4.9
Othersa	65	18.8
Number of years in general practice
<10 years	27	7.6
10–19 years	190	53.2
≥20 years	140	39.2
Postgraduate experience in tropical medicine or developing countries
No	312	85.9
Yes	51	14.1
Postgraduate training in travel medicine
No	309	84.9
Yes	55	15.1
Frequency of pretravel consultations in the last 6 months
‎    Do not counsel travellers at all	32	8.9
<10‎ consultations/ month	242	67.4
≥10 consultations/ month	85	23.7

Missing information: Age (n = 20), Country of medical degree ‎ (n = 30)

a include: Libya, Ireland, Philippines, Tunis and United Arab Emirates, Jordan, Syria, Bahrain.

Knowledge of travel vaccines and malaria chemoprophylaxis

Table 2 displays PCPs’ responses on travel vaccine recommendations for most adult travellers according to the specified destinations (Kenya, Saudi Arabia and Thailand). Most PCPs answered correctly about the vaccine recommendation of hepatitis A (85.4%) and typhoid (84.9%) for travellers going to Kenya. However, only 23.1% and 26.1% answered correctly about vaccine recommendations of cholera and rabies, respectively. Regarding travellers going to Saudi Arabia for Hajj, most PCPs answered correctly the questions about seasonal flu (92.0%) and meningococcal (95.3%) recommendations. On the other hand, few PCPs (23.6%) correctly responded to pneumococcal vaccine recommendation for pilgrims. Regarding travels to Thailand, most PCPs correctly responded to the recommendation of hepatitis A (84.1%) and typhoid (79.9%) vaccines. However, only 28.6% and 32.7% answered correctly about vaccine recommendations of yellow fever and cholera, respectively.

Table 2

Primary care physicians’ knowledge of vaccine recommendation for most adults travelling to frequent destinations from Qatar (N = 364).

Destination	Vaccine	Correct answers, n (%)	Incorrect answers, n (%)
Kenya (East Africa)	Cholera	84 (23.1)	280 (76.9)
	Hepatitis A	311 (85.4)	53 (14.6)
	Typhoid	309 (84.9)	55 (15.1)
	Rabies	95 (26.1)	269 (73.9)
Saudi Arabia (for Hajj)	Pneumococcal	86 (23.6)	278 (76.4)
	Seasonal flu	335 (92.0)	29 (8.0)
	Meningococcal	347 (95.3)	17 (4.7)
	Dengue fever	225 (61.8)	139 (38.2)
Thailand (South East Asia)	Cholera	119 (32.7)	245 (67.3)
	Hepatitis A	306 (84.1)	58 (15.9)
	Typhoid	291 (79.9)	73 (20.1)
	Yellow fever	104 (28.6)	260 (71.4)

Table 3 shows the PCPs’ responses about malaria chemoprophylaxis recommendations according to the specified destinations (Tanzania, Rural Thailand, Turkey and Sri Lanka). Most PCPs (83.2%) answered correctly to the question about malaria chemoprophylaxis recommendation for travellers to Tanzania. On the other hand, only 18.7% answered correctly about the malaria chemoprophylaxis recommendation for travellers to Sri Lanka.

Table 3

Primary care physicians’ knowledge of the recommendation of malaria chemoprophylaxis for most adults travelling to frequent destinations from Qatar (N = 364).

Destination	Correct answers, n (%)	Incorrect answers, n (%)
Tanzania	303 (83.2)	61 (16.8)
Rural Thailand	244 (67.0)	33 (8.0)
Turkey	245 (67.3)	119 (32.7)
Sri Lanka	68 (18.7)	296 (81.3)

The histogram in Fig 1 illustrates the distribution of PCPs’ overall knowledge scores about travel vaccines and malaria chemoprophylaxis recommendations. The distribution of the scores is approximately normal ranging between 0 and 16 with a mean knowledge score of 9.54 (±3.24) out of 16.

Fig 1

Distribution of primary care physicians’ overall mean knowledge scores about travel vaccines and malaria chemoprophylaxis (N = 364).

Fig 2 shows PCPs’ mean percentage knowledge scores. The mean percentage of overall knowledge score was 59.6%. The highest achieved knowledge was for vaccine recommendations for Hajj (68.0%), while the lowest score was for vaccine recommendations for ‎Kenya (54.7%).‎

Fig 2

Primary care physicians’ mean percentage knowledge scores (N = 364).

Factors associated with travel medicine knowledge

Table 4 describes the association between PCPs’ background characteristics and their overall knowledge score in TM. In bivariate analysis, the PCPs’ age, medical degree country, postgraduate experience in tropical ‎medicine or developing countries, postgraduate training in TM‎‎ and frequency of TM related consultations per month were significantly associated with the knowledge score.

Table 4

Association between primary care physicians’ characteristics and their knowledge score in travel medicine (N = 364).

Variable	Mean (SD)	p-value
Age		0.019*
<40 years old	9.30 (3.42)
40–49 years old	10.01 (3.05)
≥50 years old	8.84 (3.17)
Gender		0.187
Female	9.27 (3.12)
Male	9.73 (3.32)
Medical degree country		0.030*
Arab countries	9.18 (3.14)
Non-Arab countries	9.94 (3.27)
Number of years in general practice		0.362
<10‎ years	8.96 (3.49)
‎     ≥10 years	9.56 (3.23)
Postgraduate experience in tropical medicine or developing countries		0.016*
No	9.36 (3.28)
Yes	10.53 (2.75)
Postgraduate training in travel medicine		0.008*
No	9.35 (3.23)
Yes	10.60 (3.13)
Frequency of pretravel consultations		<0.001*
Do not counsel travellers at all	7.56 (4.39)
<10‎ consultations/ month	9.56 (3.23)
≥10 consultations/ month	10.21 (2.41)

*Statistically significant.

Predictors of travel medicine knowledge

As shown in Table 5, participants who were aged between 40 and 49 years were significantly more likely to score higher in TM knowledge compared to participants who were aged 50 years or more by 1.072 scores (95% CI: 0.230, 1.915). Also, physicians who obtained their medical degree from non-Arab countries had a significantly higher mean knowledge score compared to those who graduated from an Arab country by ‎0.748 (95% CI: 0.065, 1.432‎). As well, those with postgraduate training in TM‎ ‎ had a significantly higher mean knowledge score compared to their counterpart by a score of ‎‎‎1.405 scores (95% CI: 0.407, 2.403). ‎Lastly, the frequency of pretravel consultations per month was significantly associated with knowledge scores.

Table 5

Predictors of travel medicine knowledge among primary care physicians (multivariable linear regression analysis) (N = 364).

Variable	Adjusted difference in mean (95% CI)	p-value
Age
<40 years old	0.536 (-0.424, 1.495)
40–49 years old	1.072 (0.230, 1.915)	0.273
≥50 years old	Reference	0.013*
Gender		0.414
Female	Reference
Male	0.287 (-0.404, 0.979)
Medical degree country		0.032*
Arab countries	Reference
Non-Arab countries	0.748 (0.065, 1.432)
Number of years in general practice		0.362
<10‎ years	Reference
‎     ≥10 years	0.595 (-0.688, 1.877)
Postgraduate experience in tropical medicine or developing countries		0.227
No	Reference
Yes	0.649 (-0.407, 1.705)
Postgraduate training in travel medicine		0.006*
No	Reference
Yes	1.405 (0.407, 2.403)
Frequency of pretravel consultations
‎     Do not counsel travellers at all	Reference
<10‎ consultations/ month	1.951 (0.807, 3.095)	0.001*
≥10 consultations/ month	2.585 (1.294, 3.876)	<0.001*

Dependent variable: Knowledge mean score (ranged from 0 to a maximum of 16); *Statistically significant.

Use of information resources

Fig 3 shows the information resources used by PCPs for their practice of TM‎. Specialized internet websites ‎(e.g., CDC—Centers for Disease Control; WHO—World Health Organization)‎ were the most frequently (i.e., every time and often) cited resource (95.0%), followed by consulting other colleagues (79.6%). On the other hand, specialized textbooks and journals were infrequently cited as information resources.

Fig 3

Information resources cited by primary care physicians for travel medicine‎ advice (N = 364).

Discussion

This was the first cross-sectional study to evaluate TM knowledge and its associated predictors among PCPs working in PHC settings in Qatar. In this study, the knowledge of PCPs about travel vaccines and malaria chemoprophylaxis recommendations for selected destinations was assessed. The knowledge score was calculated based on PCPs’ answers to 16 questions. Their overall mean knowledge score was 9.54 (±3.24) out of 16 and an overall percentage knowledge score of 59.6% (±20.3). The highest achieved percentage knowledge score among PCPs was for vaccine recommendations for Saudi Arabia (Hajj) (68.0%), while the lowest score was for vaccine recommendations for Kenya (54.0%).

These results are consistent with previous studies investigating PCPs’ knowledge in TM. For example, Piotte and colleagues (2013) assessed the level of specific knowledge among PCPs in France regarding pretravel advice, vaccinations and malaria prophylaxis [23]. The knowledge score was calculated based on answers to brief pretravel scenarios. The participants’ mean knowledge score was 8 out of 15 (knowledge percentage score 53.0%). In another study in Oman that assessed the knowledge of TM in 108 PCPs, the participants’ mean knowledge score was 7.1 out of 14 (knowledge percentage score 50.7%) [24]. In contrast, a study in Saudi Arabia of 385 PCPs to assess their knowledge of TM specific to patients with diabetes mellitus reported a low mean knowledge score of 2.54/10 (knowledge percentage score 25.0%) [16]. Al-Hajri et al. in their study in Qatar found a significant improvement in PCPs’ overall knowledge in TM following an educational symposium [19]. However, they did not report PCP’s knowledge scores before or after the symposium.

In the present study, vaccine recommendations for Kenya and Thailand were correctly identified by 55.0% and 56.0% of PCPs, respectively. Moreover, malaria chemoprophylaxis recommendation for Thailand was identified by about two-thirds of PCPs. In comparison, Porter and Knill-Jones (2004) in the United Kingdom assessed practitioners’ knowledge of vaccines and malaria chemoprophylaxis recommendations for three popular destinations (Kenya, Thailand, and Turkey). They reported that 77.0% and 65.0% of respondents correctly identified the recommendations of vaccines and malaria medications, respectively [18]. Another study assessed the knowledge of 150 Swiss and 150 German PCPs about travel vaccine recommendations for two frequent holiday destinations (Kenya and Thailand). It was found that recommendations on vaccination were correctly identified by 57.0% and 61.0% of Swiss PCPs, and 38.0% and 43.0% of German PCPs for Kenya and Thailand, respectively. In addition, recommendations on malaria chemoprophylaxis were correctly identified by 93.0% and 87.0% of Swiss PCPs, and 71.0% and 55.0% of German PCPs for Kenya and Thailand, respectively [17]. The authors attributed the relatively higher knowledge of Swiss PCPs to their access to readily available and standardized information resources, which were not available to the German group.

The discrepancies in the findings among the studies described above may be explained partly by methods used to examine the knowledge (e.g., multiple choice questions; case scenarios) as well, scoring criteria and methodology applied to calculate knowledge scores. Participants’ characteristics may also influence their knowledge of TM. For instance, in the present study, the multivariable linear regression model showed that several PCP characteristics were significant predictors of a higher mean knowledge score. For instance, PCPs aged 40–49 years old were significantly more likely to have a higher mean knowledge score in TM than other age groups. This finding is supported by studies of PCPs in the USA and France [23, 25]. The high knowledge scores among PCPs who were in this age group probably indicates their higher professional competence compared to younger practitioners who might not have had enough experience in the field. On the other hand, older physicians’ relatively low mean knowledge score might be explained by not having gained the proper education and training in such an evolving speciality.

The analysis in the present study showed that the high frequency of pretravel consultations (≥10/month) was the most significant predictor of high knowledge in TM (2.585; 95% CI:1.294, 3.876). This is in line with findings of other studies. For instance, Kogelman et al. (2014) in the USA showed that knowledge scores based on pretravel scenarios were higher in physicians who counseled more pretravel patients [25]. Similarly, a study in France showed that PCPs who provided more pretravel health consultations had higher TM knowledge scores [23]. These findings suggest that practice could enhance knowledge through motivation of physicians to search for information relevant to the consultation. Thus, more and regular exposure to travel-related consultations and issues may lead to ‎higher levels of information seeking and gaining new knowledge. Such behavior in ‎physicians is important because TM is complex and necessitates the acquisition of up-to-‎date knowledge about continuously evolving risks and necessary interventions.

According to the present study findings, having previous TM training was significantly associated with higher knowledge in PCPs (1.405; 95% CI: 0.407, 2.403). This finding is consistent with other studies in the UK, Qatar, and the USA [18, 19, 25]. These findings demonstrate the beneficial effect of training in TM on the knowledge of PCPs in this field, which in turn may improve the quality of TM consultations.

The country of medical education was another predictor of high TM knowledge score. PCPs who graduated from medical schools in non-Arab countries were significantly more likely to have higher knowledge scores than those who graduated from Arab. This may be due to travel clinics and travel health services not being well-established in the Arab world. Also, TM might not be incorporated in undergraduate and postgraduate curriculum in medical schools in the Arab world.

In the present study, specialized internet websites‎ (e.g., CDC, WHO) were utilized by the vast majority of PCPs (95%) as an information resource to practice TM. Al-Hajri et al. had reported that 78.9% of PCPs utilised internet websites [19]. In contrast, several worldwide studies investigating the practice of PCPs in TM have reported lower rates. For instance, only 20% and 60% of PCPs in studies in Germany and France had utilized online information resources in their practice of TM, respectively [23, 26]. The high use of online information resources in this ‎study could be related to PCPs having easy and convenient access to them‎. Online information resources are considered easily accessible and contain evidence-based current information specific to both disease and country. Consulting other colleagues was another frequent resource on travel-related information in this study (80%). This is inconsistent with findings of the studies of PCPs in Oman (10%) [24] and France (43%) [23].‎ However, researchers from Australia have reported that human sources of information may lead to non-evidence-‎based prescribing behavior in PCPs [27].‎ Therefore, consultation with colleagues while encouraged should be done with caution.

Few PCPs in this study used specialized journals (25%) and textbooks (26%) to obtain travel-related information. Other studies in France (26%) [23] and Oman (10%) [24] reported similar findings.‎ The low utilization of specialized journals and textbooks for travel advice may be related to ‎PCPs not having enough time or skills to look for specific information from these ‎resources. Another reason could be related to the availability and accessibility of these resources which concurs with findings in other studies [28, 29]. ‎‎It is widely accepted that hard copy resources such as textbooks may rapidly become outdated [30]. For competent TM practice, PCPs need to have access to relevant, current, and evidence-based resources.

Strengths and limitations

This study has a number of strengths. First, the study was the first of its kind in Qatar to evaluate TM knowledge and its predictors among PCPs. Second, the study achieved a high response rate (89.2%) despite the high demands on PCPs ‎caused by the COVID-19 pandemic which could be explained by their interest in this ‎topic and by communicating clearly and concisely the objectives of the survey and that the data collector will follow up with those who do not respond.‎ Finally, the results of this study represent PCPs’ responses from all 27 PHC centers in Qatar. Thus, the findings may be broadly generalizable to the overall general practice in Qatar. However, the cross-sectional design of this study limits its interpretation of the temporal relationship between the variables (e.g., does more practice lead to better knowledge or did better knowledge lead to more practice?).

Conclusion

The overall PCPs’ mean percentage knowledge score of TM was 59.6% (±20.3). A high volume of pretravel consultation, prior training, middle age group, and medical degree from non-Arab countries were significant predictors of higher ‎knowledge. Online information was the main reported resource of TM consultation. The provision of TM education and training that is standardized, evidence-based, and readily available ‎to all PCPs, particularly those who provide few pretravel consultations, graduates of Arab ‎countries, and those who lacked previous training and experience in the field is highly recommended to narrow the gap in TM knowledge, which ultimately will promote the ‎health of the travelling public.

Another implication for PHC centers is to highlight the importance of adequate exposure of PCPs to travelling patients by encouraging them to take all healthcare encounters as an opportunity to ‎provide pretravel health consultations.‎ Finally, PHC centers should ensure that all PCPs have access to authoritative web-based resources which provide up-to-date country and disease-specific information.

Study questionnaire.

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9 Feb 2022

21 Feb 2022

RESPONSE TO REVIEWERS

Re: "Primary Care Physicians’ Knowledge of Travel Vaccine and Malaria Chemoprophylaxis and ‎Associated Predictors in Qatar"‎

General response to the reviewers’ comments: We appreciated the many insightful comments ‎‎made by the reviewers. We studied them ‎carefully and made diligent efforts in revising our ‎‎manuscript. We believe we have responded to each of their ‎comments, and as a ‎result, we ‎consider our ‎manuscript much improved to the reviewers’ satisfaction. ‎Where ‎necessary, we have ‎made revisions to the manuscript. Our revisions are indicated with track changes in the marked-up ‎copy of the manuscript.‎

Reviewer comments: Reviewer 1

Comment #1: This study is a cross-sectional survey of travel medicine knowledge among primary ‎care providers in Qatar. The paper is clearly written, and results are nicely contextualized within ‎the broader literature. Introduction: Authors describe that “travel health services are insufficient ‎and not well-established” in Qatar but what does this mean practically? Are there established ‎travel health clinics? Are visits and malaria chemoprophylaxis covered under public or private ‎health insurance?‎

Response: Thank you for your positive feedback and comment. Please see revised text in the ‎manuscript lines 104-108. “Travel Medicine services including travel vaccines and malaria ‎chemoprophylaxis, are ‎mainly provided by non-‎specialized PCPs practicing in PHC centers, but do ‎not cover ‎comprehensive travel advice. The ‎services are provided free of charge for Qatari citizens ‎‎and highly subsidized for non-Qatari ‎residents”‎.‎

Comment #2: I think it would be helpful context for readers for the authors to describe the ‎epidemiology of malaria + other travel-related illnesses in Qatar – namely, is this a problem? What ‎is the incidence rate and how does it rank in comparison to other travel-related illnesses? Is it ‎legislatively reportable to public health? Who are the risk groups and what are the main countries ‎of travel?‎

Response: Thank you for your insightful comment.‎ We have added a paragraph about the ‎epidemiology of malaria and its incidence rate. We have addressed your comment in the ‎introduction section (please see lines 60-66). “A study in Qatar about the epidemiology of malaria ‎showed that the incidence rate of ‎imported malaria had increased from 15 to 19 cases per 100,000 ‎from 2008 to 2015, ‎respectively. The majority of the cases were imported from malaria-endemic ‎countries such ‎as India, Nepal, Pakistan, and Sudan and were reported mainly among adult male ‎expatriates ‎and those who visited relatives and friends‎ [10]. While malaria is legislatively ‎reportable to ‎the Ministry of Public Health in Qatar‎, no data are available for other travel-related ‎‎illnesses”‎

Comment #3: The statement “they are positioned to be the most suitable healthcare practitioners ‎to practice TM [11, 12]” needs some qualifiers. This statement may be true in Qatar if there is no ‎infrastructure to support specialized travel medicine clinics that would be staffed by physicians ‎with expertise in TM. Perhaps either “in Qatar” should be added to the end of this sentence or ‎alternatively, authors could modify the sentence to remove judgement re: who is most suitable ‎and rather state that PCPs are an important provider of TM.‎

Response: Thank you for your suggestion. We have added “in Qatar” to the end of the sentence. ‎‎(Please see line 70).‎

Comment #4: Change “purposes” to “objectives” in the final sentence of the introduces.‎

Response: Thank you for your comment. We have changed “purposes” to “objectives” as ‎suggested. (Please see line 90).‎

Comment #5: Methods: Recruitment – What constituted “eligible” PCPs? It sounded like all were ‎eligible. Also, were the eligible PCPs approached in person? Could more details be provided on ‎recruitment? In Canada, most primary care physicians were providing primarily virtual care early in ‎the pandemic. What was the situation in Qatar? The response rate was high. Were incentives or ‎compensation provided?‎

Response: Thank you for your comment. ‎

• This is correct, all PCPs were eligible. We meant by “eligible” those who were not available at ‎the time of data collection (e.g., in quarantine or on sick leave due to COVID-19 infection). ‎Please see lines 117 for revised text.‎

• To clarify, at the time of data collection, there were no virtual consultations but were ‎implemented later.‎

• PCPs were approached in person in their clinics (Please see line 118). ‎

• There were no incentives or compensation provided (Please see line 123). ‎

• The study achieved a high response rate (89.2%) despite the high demands on PCPs ‎caused ‎by ‎the COVID-19 pandemic which could be explained by their interest in this ‎topic and ‎by ‎communicating clearly and concisely the objectives of the survey and that the data collector ‎will follow up with those who do not respond. Please note that we have clarified this in the ‎manuscript (Please see lines 343-347).‎

Comment #6: Survey - How was the survey formulated and was there a conceptual model that ‎guided your survey development? Were any of the questions taken from validated surveys? How ‎were the destinations selected - informed by frequent travel destinations of reportable travel-‎related infections? travel patterns from Qatar? The details should be provided and if possible, a ‎copy of the questionnaire included as a supplemental file. (Note: I see the destinations are ‎described in the discussion – i.e., frequent holiday destinations of travellers from – this should be ‎moved up to the methods where you explain the survey).‎

Response: Thank you for your insightful comment.‎ ‎

• We formulated our survey based on an extensive literature review and input from travel ‎medicine experts in order to have a comprehensive tool that will fulfill the study objectives. ‎Unfortunately, the autohrs of the articles we found reported on the validation of the ‎instruments that used.‎

• The destinations were selected based on being frequent travel destinations of travellers from ‎Qatar. We have explained this in the method section (Please see lines 139-140).‎

• I have included a copy of the questionnaire as a supplemental file.‎

Comment #7: How were postgraduate experience in tropical medicine or developing countries, ‎postgraduate training in TM defined?‎

Response: Thank you for your comment. ‎

• Postgraduate experience in tropical medicine or developing countries was defined as any ‎engagement in travel medicine practice after graduation from medical school. It was assessed ‎by asking a close-ended question.‎

• Postgraduate training in TM was defined as receiving any postgraduate degree (Diploma, ‎Master, PhD) or training (workshop, certified short course) or having a membership or ‎fellowship of TM related professional organization. It was also assessed by asking a close-‎ended question.‎

• Please see lines 132-135 in the manuscript.‎

Comment #8: Outcome measurement - The scores computed could range from 0 to 16. What ‎threshold was used to assess adequate or sufficient knowledge? This seems important to the ‎interpretation of your study findings, especially as you describe overall knowledge as inadequate in ‎your abstract.‎

Response: Thank you for your comment.‎ We did not use a threshold to assess ‎adequate/inadequate knowledge of TM. We calculated the mean score (‎9.54 ±3.24 out of 16 )‎ and ‎we built a multivariable linear regression model to identify predictors of higher ‎knowledge‎ score. ‎Please note that we have removed the description "adequate" from the conclusion section.‎

Comment #9: Chronbach’s alpha – Could you please provide a reference for your assessment that ‎your value was acceptable?‎

Response: Thank you for your comment.‎ We have provided a reference for good Chronbach’s ‎alpha value [referecne #22].‎

Comment #10: “59.1% were males” – should be changed to 59.1% were male physicians or else ‎‎59.1% were men.‎

Response: Thank you for your suggestion.‎ We have changed this in the manuscript.‎

Comment #11: From Figure 1, it looks like there were ~10 physicians with a score of 0. Did these ‎respondents have 0 correct answers or were these a result of missing data/blanks? The authors do ‎not describe how missing data was dealt with in the analysis.‎

Response: Thank you for your insightful observation. We double-checked the datasheet and found ‎that 9 physicians scored ‎zero due to either incorrect or “don't know” answers (please see lines 140-‎‎142). Missing data were dealt with through list-wise deletion. We have included this in the ‎manuscript under “Statistical analysis” section (line 156).‎

Comment #12: There has been a similar study conducted in Qatar and so any references to this ‎paper being the first study on PCP knowledge of TM in Qatar should be removed i.e., first line of ‎the discussion (see - Al‐Hajri M Bener A Balbaid O Eljack E. Knowledge and practice of travel ‎medicine among primary health care physicians in Qatar. Southeast Asian J Trop Med Public Health ‎‎2011; 42:1546–1552). This work should be reviewed by authors and referenced in their ‎introduction and discussion. The statement in the intro “However, little is known about their ‎knowledge of TM” should be revised to indicate there is little CURRENT data on this topic in Qatar.‎

Response: Thank you for bringing this matter to our attention. ‎

• We were aware of Al‐Hajri et al. study. However, we believe that our study is the first that ‎examined the predictors of TM knowledge among PCPs in Qatar, which were not examined by ‎Al-Hajri et al.’s article. In addition, these authors did not calculate the knowledge score; ‎instead, they reported mere frequencies of the correct answers pre- and post-symposium.‎

• Please note that we have reviewed and referenced Al‐Hajri et al.’s study in our revised ‎manuscript [Introduction: lines 85-89] and in the [Discussion: lines 264-266 and lines 320-321].‎

• We have modified the statement in the intro to “However, little is known about their ‎knowledge of TM” as suggested (Please see line 89-90).‎

Comment #13: Authors do not discuss the implications of their work. This work replicates findings ‎from both Qatar and other regions and in that respect, is not novel. Given that, the findings should ‎be placed in context with the current state of travel medicine training and provision in Qatar. What ‎should ideally be done differently based on the results of your survey? How can your findings be ‎used to effectively improve TM knowledge among PCPs?‎

Response: Thank you for your insightful comment. Kindly note that we had discussed the ‎implications of our study findings under the Conclusion section. However, we have modified it to ‎be more specific to our findings (Please see lines 357-366).‎

Reviewer comments: Reviewer 2‎

Comment #14: I notify that it is a good article, and it meets the scientific requirements.‎

I just have minor comments.‎ ‎

• At the level of the section Predictors of travel medicine knowledge, we have the impression ‎that the ‎figure exists before the text, but it is the text that must announce the figure. Is this ‎not a mistake? ‎

• I ‎also suggest documenting evidence of obtaining verbal consent from study participants. ‎

• At the level ‎of discussion, the beginning of the paragraph I suggest replacing "examine" with ‎‎"evaluate"‎.‎

Response: Thank you for this positive feedback and suggestion. ‎

• We agree that the text proceeds the figure. As you can see in the following sentence copied ‎from the predictors section “As shown in Table 5, participants who were aged between 40 and ‎‎49 years were significantly ‎more likely to score higher in TM knowledge compared to ‎participants who were aged 50 ‎years or more by 1.072 scores (95% CI: 0.230, 1.915)” the text ‎preceeds the figure. ‎

• Kindly note that we have documented evidence of obtaining verbal consent from study ‎participants‎ under the Ethical Considerations subheading (Please see lines 163-164).‎

• Kindly note that we replaced "examine" with "evaluate"‎ as suggested (Please see line 244).‎

Journal Requirements:‎

‎1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for ‎file naming.‎

Response: Please note that we have reviewed PLOS ONE's style requirements and edited our ‎manuscript accordingly.‎

‎ ‎

‎2. We note that participants provided oral consent. Please also state in the Methods:- Why written ‎consent could not be obtained- Whether the Institutional Review Board (IRB) approved use of oral ‎consent- How oral consent was documented.‎

Response: Thank you for your observation. We believe it was a misprint. Please note that we have ‎obtained written consent from study participants. We have corrected this in the manuscript.‎

‎3. Please include additional information regarding the survey or questionnaire used in the study ‎and ensure that you have provided sufficient details that others could replicate the analyses. For ‎instance, if you developed a questionnaire as part of this study and it is not under a copyright ‎more restrictive than CC-BY, please include a copy, in both the original language and English, as ‎Supporting Information.‎

Response: Please note that we have described our questionnaire in the Methods section and we ‎included a copy of the study questionnaire as Supporting Information.‎

‎4. Please note that funding information should not appear in the Acknowledgments section or ‎other areas of your manuscript. We will only publish funding information present in the Funding ‎Statement section of the online submission form. Please remove any funding-related text from the ‎manuscript and let us know how you would like to update your Funding Statement. ‎

Response: Please note that we have removed funding-related text from our manuscript and we ‎included amended statements within the cover letter as requested. ‎

In addition, please note that in the case Qatar National Library (QNL) cover the article processing ‎charges (APC) of our publication, we will need to add the following statement in the ‎acknowledgment section of the article: "Open Access funding provided by the Qatar National ‎Library”. This is a requirement of the library.‎

Please ‎update the Funding Statement section of the online submission form as follow:‎

• Initials of the authors who received each award: Ayman Al-Dahshan (AAD)‎

• Grant numbers awarded to each author: MRC-01-19-324. ‎

• The full name of each funder: Medical Research Center (MRC) at Hamad Medical Corporation, Doha, ‎Qatar

• URL of each funder website: https://www.hamad.qa/EN/Education-and-‎research/Medical_Research/Pages/default.aspx

• The funders had no role in study design, data collection and analysis, decision to publish, or preparation ‎of the manuscript.‎

‎5. Please note that in order to use the direct billing option the corresponding author must be ‎affiliated with the chosen institute. Please either amend your manuscript to change the affiliation ‎or corresponding author, or email us at plosone@plos.org with a request to remove this option.‎

Response: Please note that Qatar National Library (QNL) may cover the article processing charges ‎‎(APC) of our publication. In that case, we will request an unpaid invoice that is addressed to the ‎library.‎

‎6. 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 your comment. Please note that we have double-checked the reference ‎list and made the following changes:‎

• We have updated reference number 7 to be: [7] Angelo K, Kozarsky P, Ryan E, Chen L, Sotir M. ‎What ‎proportion of international travellers acquire a travel-related illness? A review of the ‎literature. ‎Journal of Travel Medicine, vol. 24, no. 5, 2017. ‎

• We have removed reference number 23 because we noted ‎that it is no more accessible (retracted).‎‎ ‎‎[A. Al-Ghamdi, A. Ibrahim, M. Al-Ghamdi, E. Ryan and R. Al ‎Raddadi, '"Primary Health Care ‎Physicians ‎Knowledge About Travel Medicine Interventional ‎Study," International Journal of ‎Academic Research, ‎vol. 7, no. 2B, pp. 516-20]‎

Submitted filename: Response to Reviewers - PNOE-D-21-28199.pdf

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11 Mar 2022

Primary Care Physicians’ Knowledge of Travel Vaccine and Malaria Chemoprophylaxis and Associated Predictors in Qatar

PONE-D-21-28199R1

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23 Mar 2022

PONE-D-21-28199R1

Primary Care Physicians’ Knowledge of Travel Vaccine and Malaria Chemoprophylaxis and Associated Predictors in Qatar

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