Black flies and Onchocerciasis: Knowledge, attitude and practices among inhabitants of Alabameta, Osun State, Southwestern, Nigeria.

BACKGROUND AND OBJECTIVES: This study reports knowledge of residents of Alabameta community, Osun State, Nigeria on the bioecology and socio-economic burden of black flies and onchocerciasis.
METHODS: Using structured questionnaires and Focus Group Discussion (FGD), a total of 150 community respondents participated in the study.
RESULTS: The knowledge of the residents on the existence of black flies in the community was significant (p<0.05) as all the 150 respondents confirmed the presence of black flies with the local name 'Amukuru' i.e causing itching. However, their lack of knowledge of the flies breeding site (104) (69%), prevention (134) (89%), cause (132) (88%), and treatment (133) (89%) of onchocerciasis was profound. Majority 147(98%) of the respondents reported that flies bite more in the wet season as against dry season 3(2%) and have a higher affinity (124) (82%) for biting the leg than any other part of the body. A larger percentage (89%) of the respondents are unaware of any medication for the treatment of onchocerciasis while 11% are aware. There had been no sensitization on onchocerciasis according to 89% of the respondents.
CONCLUSION: Due to lack of resident's knowledge on black flies bioecology which may continuously expose them to the bite of the flies and ultimately infection, it is paramount that the Osun State government and the NTD implementing partner map out new public health education strategies during routine Mass Administration of Medicines with Ivermectin with a view to preventing onchocerciasis infection as well as man-vector contact.

Introduction

Among the filarial nematodes, the public health significance of Onchocerca volvulus cannot be overemphasized being the causative organism of the dreadful and debilitating disease onchocerciasis [1]. O. volvulus, is transmitted by members of Simulium damnosum complex (black flies) through their bite while taking a blood meal. The flies breed in fast flowing, well–oxygenated rivers and streams where the female lay her egg and the larval and pupal stages of the vector develop [2]. Adult worms mates and produces tiny juvenile worms that migrate throughout the skin and eyes, causing the various symptoms of the disease [3,4].

The disease occurs mainly in tropical areas with more than 99% of infected people living in 31 countries in sub-Saharan Africa [5]. Human onchocerciasis (river blindness) causes severe itching and various skin changes with some infected people developing eye lesions that could lead to temporary or permanent blindness while nodules containing the adult worm [5].The disease is known to be endemic in many tropical countries with 18 million people infected worldwide and 120 million people at risk of the disease [6].

In Nigeria, the first case of onchocerciasis was reported by Parson in northern Nigeria in 1908 [7]. Nigeria ranks among countries that are endemic [8] with prevalence in all her states except Lagos, Katsina, Bayelsa and Rivers according to the Nigeria onchocerciasis elimination plan [2]. Studies have shown that six of the nine main West African members of the Simulium damnosum complex are present in Nigeria [9]. The species include Simulium sirbanum, S. damnosum sensu stricto, Simulium sanctipauli, Simulium soubrense, Simulium squamosum, Simulium yahense. The first two pairs are known as Savannah flies transmitting the savannah strain of O. volvulus while the remaining are forest flies transmitting the forest strain of the parasite causing more of skin diseases than blinding [10,11].

Osun State, a south-western state is mesoendemic for onchocerciasis with sixteen endemic Local Government areas (LGA) according to the rapid entomological mapping of onchocerciasis in Nigeria in 1995 and 1996. The state has a prevalence level of at least 20% and 40% onchocercal nodules and skin microfilarial infection respectively [12]. Although, there are reports on bioecology, larva ecology, species composition of black flies in the state. The reports have not been holistic, thus the need for further studies in other parts of the state with a view to understanding better the bioecology and socio-economic burden of both the vector and disease in order to assist in the effective planning of control methods in the state.

The present study therefore seeks to provide information on community knowledge, attitude and practice in Alabameta, Osun State, Nigeria on bioecology and socio-economic burden of black flies with a view to understanding its public health implication. This will help in planning effective control strategies in the study area and Osun State, Nigeria at large.

Materials and methods

Ethics statement

Ethical approval was sought and obtained from the Osun State University Health Research Ethics Committee. Verbal Consent of guardian of participants below age eighteen was sought and obtained.

Study Area: The study community is located in Ife South Local Government of Osun State, Southwest, Nigeria with an area of 730 km2 and a population of 135,338(2006 census). Owena River transverses the community and extends to Ondo State. The river usually produces rapids along its course which serves as conducive breeding sites for S. damnosum [13].

Alabameta had been previously surveyed for onchocerciasis with a prevalence of 33.3% [14]. The intense biting of black flies had been reported in the community. This characteristics informed its selection for this study. The community lacks basic social amenities such hospital/clinic, electricity, pipe borne water, hospitals, good roads, and recreation center. Despite the high prevalence of onchocerciasis in the community, the community (nor neighboring communities) has not been enrolled on annual treatment of Mass Drug Administration. This may be partly due to its location as Alabameta is one of the hard to reach communities in Ife South Local Government of Osun State. The community population is about 300 of which majority are youths and school aged children.

Community awareness and mobilization was conducted prior to the commencement of the study through the village head and the head of the community secondary school to educate residents on the public health hazard of black flies and onchocerciasis.

Questionnaire Administration and Focus Group Discussion (FGD): The residents of the community were mobilized for the survey. A total of 150 structured questionnaires were administered to consented community members that are fifteen years and above to assess their knowledge on the bioecology and socioeconomic burden of the black fly. The questions captured the place of bite, season/month with the highest biting incidence and time, breeding site, effects of bite, body part mostly bitten and ways adopted to preventing fly bite. The questionnaires were complemented with Focus Group Discussion (FGD) of seven participants which included old men, old women and youths. The questions for the focus group discussion were unstructured and targeted at seeking information about the resident’s general knowledge on the bioecology, attitudes and practice against black flies.

Data Analysis: The data from the study was subjected to T-test and Chi-square to determine the significant difference in dynamics and bioecology of black flies during the period of the study. All analysis was performed using SPSS version 17.

Results

A total of 150 respondents were interviewed. Respondents within the age bracket 31–50 (69) (46%) were represented at a higher proportion than those within the age brackets 15–30 (54) (36%) and 51 above (27) (18%). There were more male respondents (76) (51%) than female respondents (74) (49%). About 51% (76) of the respondents were without formal education while 6% were educated up to tertiary level. Farming was the major occupation (48%), followed by trading (26%) and fishing (11%) (Table 1).

Table 1

Demographic data of respondents of the community.

Characteristic	Age group	No. of respondent	Percentage %
Age	15–30	54	36
	31–50	69	46
	51 above	27	18
Gender	Male	76	51
	Female	74	49
Educational Level	Primary	31	20
	Secondary	34	23
	Tertiary	9	6
	None	76	51
Occupation	Farming	73	48
	Fishing	16	11
	Trading	39	26
	Student	12	8
	Others	10	7

Table 2 summarizes the knowledge and attitude of respondents on bioecology of S. damnosum complex. All the respondents 150 (100%) affirmed that they know black flies when probed of the presence of the fly in the community with its local or common name ‘Amukuru’ i.e causing itching. They unanimously established the fact that the flies bite seriously in the community. A larger percentage (73%) of the respondents established that the flies bite mostly at the riverside (Owena River), while 27% claimed they bite mostly at the farm. Information from the Focus Group Discussion (FGD) corroborated these observations. The flies were believed to be biting any part of the exposed body but with affinity for the leg (124) (82%) than any other part of the bodies. This is also affirmed during the FGD. The major effect of the fly’s bite was attributed to itching by the respondents (80%) while 28(19%) respondents claimed it causes swelling.

Table 2

Knowledge and attitude of respondents on bioecology of Simulium damnosum complex.

Parameter	Response	No. of Respondent	Percentage
Have you heard of black flies?	Yes	150	100
	No	0	0
Do they bite in your community?	Yes	150	100
	No	0	0
Where do they bite in the community?	Farm	38	25
	Riverside	109	73
	House	2	1
	Others	1	1
Which part of the body do they often bite?	Head	9	6
	Neck	13	9
	Leg	124	82
	Others	4	3
What are the effects of their bite?	Itching	121	80
	Swelling	28	19
	Others	1	1
Where do they breed?	River	46	31
	Tree	104	69
	Others	0	0
Which season do they bite most?	Wet	147	98
	Dry	3	2

About 69% of the respondents claimed that black flies breed in tree holes. Respondents during FGD also ascribed the breeding of black flies to tree holes such as ‘Iroko kekere’ and ‘Igi araba”. Most of the respondents confirmed that black flies bite more in the wet season 147(98%) as against dry season 3(2%)

Table 3 shows that 88% of the respondents were ignorant of black flies as vectors of onchocerciasis. The level of ignorance was also evident among participants in the Focus Group Discussion (FGD). 36% believed onchocerciasis is caused as a result of mosquito bite, 23% attributed it to witchcraft, 11% claimed it’s the consequence of eating kola nut, 3% see it as being hereditary while 27% have no idea of its cause.

Table 3

Knowledge of respondents on onchocerciasis, causes and treatment.

Parameter	Response	No. of Respondent	Percentage
Do you know black flies cause onchocerciasis?	Yes	18	12
	No	132	88
If no, what causes onchocerciasis?	Witchcraft	34	23
	Hereditary	5	3
	Mosquitoe bite	54	36
	Eating kola nut	16	11
	No idea/uncertain	41	27
Are you aware of any medication for onchocerciasis?	Yes	17	11
	No	133	89
Is the medication orthodox or tradition?	Orthodox	5	3
	Traditional	12	8
Is onchodermatitis curable?	Yes	3	2
	No	2	1
	Uncertain	145	97

A larger percentage (89%) of the respondents is unaware of any medication for the treatment of onchocerciasis while 11% are aware. However, few respondents claimed the use of orthodox medicine while 8% claimed it is traditional.

Table 4 summarizes the knowledge of respondents on methods of black flies bites prevention. There had hardly been any sensitization on onchocerciasis according to 89% of the respondents and later confirmed during the FGD. However, 91 (60%) of respondents prevent fly bite by clothing their bodies (such as wearing socks, long garments and sweater) while 52 (35%) rub ointment such as palm oil or mosquito repellent creams. Biting is usually intense in the morning according to 83% of the respondents, followed by evening (24) (16%) while fly bite in the afternoon is the least (1) (1%). After fly bites, majority 48% do nothing apart from killing the fly, 10% rub ointment, 7% go to the hospital while 4% take drugs (particularly antimalarial drugs).

Table 4

Knowledge of respondents on methods of prevention of black flies bite.

Parameter	Response	No. of Respondent	Percentage
Has there been any sensitization on onchocerciasis?	Yes	16	11
	No	134	89
How do you prevent the flies from biting?	Clothing	91	60
	Rubbing of ointment	52	35
	Others	7	5
What time of the day is biting intense?	Morning	125	83
	Afternoon	1	1
	Evening	24	16
What do you do after fly bite?	Take drugs	6	4
	Go to hospital	11	7
	Rub ointment	15	10
	Nothing	71	48
	Others	47	31

Discussion

The result on perception of the community residents on bioecology of black flies showed that they are conversant with the black fly bites. A larger population of the residents affirmed that the flies bite mostly along the river side corroborating the scientific findings that people working close to the rivers are at the high risk of Simulium biting nuisance and onchocerciasis [15,16]. The reason for the impressive knowledge of the daily and seasonal distribution of the flies could be attributed to the long time presence of Simulium in the area. Furthermore, the river serves as a major source of water for domestic and occupational demand. Therefore reducing man-fly contact by refraining from such high biting areas of Simulium is paramount in controlling onchocerciasis.

The knowledge of the residents revealed that the flies bite mostly in the wet season than in the dry season which is in consonance with findings by [17]. This indicates that there is a higher risk of exposure to onchocerciasis in the wet season than in the dry season due to increase in adult fly population during the wet season. Thus, disease control is best carried out in the dry season since it gives a better chance for the destruction of the breeding site which invariably leads to the eradication of the flies.

Also, the poor knowledge of the residents on the breeding sites of S. damnosum s.l could increase their risk to onchocerciasis as majority of the residents do not have accurate knowledge of their breeding sites. This conforms to earlier reports on the poor knowledge of endemic communities on the ecology of S. damnosum s.l in many parts of Nigeria [18-20]. Majority of residents attributed the breeding site of black flies to trees and surrounding high vegetation. This misconception on the bio-ecology of the black flies could be as a result of the behavior of the flies in periods when the relative humidity is very low. Black flies are known to hide under shades and tree canopies [21]. Therefore, attributing the breeding sites of the vector to trees by residents may be due to their ignorance of the insect bio-ecology.

Majority of the respondents agreed that itching, pain and skin irritation are some of the observable effects of the bites of the fly. Skin disfiguration, lesions due to severe itching and scratching are some of the recognizable manifestations of onchocerciasis in many affected individuals [13,20].

Furthermore, 88% of the residents do not understand the aetiology of onchocerciasis as many assumed it is caused by mosquito bites. This assumption could be as a result of lack of sensitization and low level of awareness of the cause of the disease in the study area, this ignorance may lead to the persistence of onchocerciasis in the community. Public health enlightenment on black fly and onchocerciasis is therefore paramount for community members in a view to preventing the disease.

Since the residents lack knowledge of the cause of onchocerciasis, it is not unlikely their ignorance of the treatment for the disease as shown in the result. There is therefore the need for urgent sensitization on the treatment of the disease through the distribution of ivermectin to residents who possibly show the disease symptoms. There is also the need for them to be acquainted not only with the available medications and modern tools for controlling human onchocerciasis but with an acceptable way of knowing the causative agent, mode of transmission and preventive measures. Visual demonstrations of parasite development in Simulium flies, transmission through their bites and identification of adult parasites in excised nodules may prove to be an effective tool in a health education programme.

Although, many reported to wear protective clothing when on the farms to prevent the flies from biting (p = 0.088; p>0.05). This mode of dressing in the period when farmers are preparing their farmlands for the next planting season is usually very uncomfortable, increases their body heat and retains sweats. Respondents in this study complained of the discomfort they endure while on the farm leading to them putting on cloths that exposes their lower legs and arms which exposes them to fly bite and consequently the risk of onchocerciasis. This is sequel to their claim that the fly bite do not prevent them from work or going out for their daily activities (p = 0.304; p>0.05).

The current study shows that the residents of the study community are unaware of the bioecology of blackflies and public health implication of onchocerciasis. Thus, necessitating the need for urgent intervention of the government at both the state and federal levels as well as public health organizations through effective community awareness with a view to eradicating the disease.

9 Jun 2021

Dear Mr Busari,

Thank you very much for submitting your manuscript "Black flies and Onchocerciasis: Knowledge, attitude and practices among inhabitants of Alabameta, Osun State, Southwestern, Nigeria" for consideration at PLOS Neglected Tropical Diseases. As with all papers reviewed by the journal, your manuscript was reviewed by members of the editorial board and by several independent reviewers. The reviewers appreciated the attention to an important topic. Based on the reviews, we are likely to accept this manuscript for publication, providing that you modify the manuscript according to the review recommendations.

I thank the authors for submitting their work for our consideration. I agree with the reviewers that the manuscript addresses some novel aspects of onchocerciasis control efforts and should be published after minor revision. The reviewers identify a number of issues around the writing and presentation of the manuscript that require attention and improvement. I look forward to receipt of a suitably revised version of the paper and again thank the authors for submitting it to PLoS-NTDs

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Important additional instructions are given below your reviewer comments.

Thank you again for your submission to our journal. We hope that our editorial process has been constructive so far, and we welcome your feedback at any time. Please don't hesitate to contact us if you have any questions or comments.

Sincerely,

Timothy G. Geary, PhD

Deputy Editor

PLOS Neglected Tropical Diseases

Timothy Geary

Deputy Editor

PLOS Neglected Tropical Diseases

***********************

I thank the authors for submitting their work for our consideration. I agree with the reviewers that the manuscript addresses some novel aspects of onchocerciasis control efforts and should be published after minor revision. The reviewers identify a number of issues around the writing and presentation of the manuscript that require attention and improvement. I look forward to receipt of a suitably revised version of the paper and again thank the authors for submitting it to PLoS-NTDs

Reviewer's Responses to Questions

Key Review Criteria Required for Acceptance?

As you describe the new analyses required for acceptance, please consider the following:

Methods

-Are the objectives of the study clearly articulated with a clear testable hypothesis stated?

-Is the study design appropriate to address the stated objectives?

-Is the population clearly described and appropriate for the hypothesis being tested?

-Is the sample size sufficient to ensure adequate power to address the hypothesis being tested?

-Were correct statistical analysis used to support conclusions?

-Are there concerns about ethical or regulatory requirements being met?

Reviewer #1: 1st paragraph

-730 kilometer square = 730 km²

Reviewer #2: The background and rationale for the study are not well articulated. Therefore, although the study is to provide the knowledge attitudes and practices of the study population, it is difficult to know what the hypothesis was being tested. The statistics was to find difference in dynamics and transmission potential of blackflies. This is not possible through a questionnaire survey. One cannot determine transmission potential of vectors without undertaking vector studies.

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Results

-Does the analysis presented match the analysis plan?

-Are the results clearly and completely presented?

-Are the figures (Tables, Images) of sufficient quality for clarity?

Reviewer #1: 1st paragr.

-what means “Respondents ….were higher than those…” ? You probably mean “were represented at a higher proportion…”

-delete “while students made up the rest of the respondents (8%)”

-is there actually a translation for “Amukuru”?

Reviewer #2: The study was supposed to have used some statistics in the analysis of the data, yet this is not seen in the results presented. One cannot therefore make any inferences on the analysis plan. The tables could be compressed to provide the key observations while the raw data could be added as an extra file

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Conclusions

-Are the conclusions supported by the data presented?

-Are the limitations of analysis clearly described?

-Do the authors discuss how these data can be helpful to advance our understanding of the topic under study?

-Is public health relevance addressed?

Reviewer #1: (No Response)

Reviewer #2: The conclusions do not reflect on the data presented. The study's relevance does not come out clearly in the light of current onchocerciasis elimination goals. One key element of the study is not the knowledge on blackflies but the fact that there has not been any drug distribution in the community and the lack of knowledge of the treatment for the disease. The conclusion should advocate for either onchocerciasis elimination mapping in the area or the start of an alternate treatment strategy if the level of endemicity is already known. However, none of this is mentioned in the manuscript. Also there is less clarity in the report

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Editorial and Data Presentation Modifications?

Use this section for editorial suggestions as well as relatively minor modifications of existing data that would enhance clarity. If the only modifications needed are minor and/or editorial, you may wish to recommend “Minor Revision” or “Accept”.

Reviewer #1: The acknowledgment is inappropriate. It should not thank any of the co-authors, nor family members or just anyone “who have contributed in one way or the other“. Only if there were specific contributions to be mentioned. On the other hand, was there any field staff to be mentioned here, and what about the community leaders/chiefs who certainly had to agree to the study in their village?

References:

Seem to be carelessly arranged! In the introduction, “WHO, 1994“ is cited, but not listed. Also, the references are not in strict alphabetical order, and different formats are used (journal abbreviated or not?; author initials with or without dots). Opara et al. is only cited for the 2005 paper, so no 2005a necessary.

Reviewer #2: I find the study of benefit to the elimination agenda for Nigeria. However, this is not demonstrated in the rationale for why the study was undertaken. The write up is also full of some mix ups. For example the authors indicate that the population is unaware of the bioecology of vectors while at the same time indicating that they are aware of the biting period in the day and season as well as which part of the body they prefer to bite.

There should be a logical sequence in the write up starting from the abstract.

There should be clarity in data interpretation. For example at a point the authors indicate "Majority of residents attributed their breeding site to a tree “Iroko kekere” or “Igi araba and as such do not really pay attention to fly bite". Yet in another section indicate that the population wears protective clothing to prevent bites.

There is a need for a complete rewrite this manuscript but not necessarily getting new data

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Summary and General Comments

Use this section to provide overall comments, discuss strengths/weaknesses of the study, novelty, significance, general execution and scholarship. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. If requesting major revision, please articulate the new experiments that are needed.

Reviewer #1: The paper presents some rarely reported insights of local knowledge “at the end of the road” with regard to oncho and its vectors. Though easily ignored by the expert community, this knowledge can play a crucial role in oncho elimination efforts. Apart from some specific issues listed below, I would just like to point out the following for revision:

Since an APOC REMO in 2008 is mentioned, was there ever any oncho control interventions in the particular area? MDA? Can you give any prevalence data? Furthermore, this question should be addressed in the discussion. If people were never confronted with MDA or other oncho control activities, how should they know more about the disease? In any case, the conclusion still remains valid that health education needs to be implemented.

Reviewer #2: Overall i feel the study needs revision to be accepted for publication. There is a need for a completely re-haul of the write up to bring some clarity.

The strength of the manuscript is in the information it provides that there are still many areas with endemic onchocerciasis yet with not knowledge of elimination efforts.

Unfortunately, the rationale for the study is not well articulated and the write up has many lapses of mixed up information. In the methodology section, one would expect to know what was done before the ethical approval is provided. The results section has no statistics for any of the observations made and finally, the discussion section is poorly written

There are many statements that needs clarity Examples are

: "Alabameta is highly endemic with onchocerciasis with low community microfilarial load"

“It is endemic in many tropical countries”

“There were more male respondents (76) (51%) than female respondents (74) (49%).” Is this statistically different?

Please attached document.

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Reviewer #1: No

Reviewer #2: Yes: Daniel Boakye

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References

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6 Aug 2021

Submitted filename: -plosntd revised response to reviewers comments.docx

Click here for additional data file.

22 Jan 2022

Dear Mr Busari,

Thank you very much for submitting your manuscript "Black flies and Onchocerciasis: Knowledge, attitude and practices among inhabitants of Alabameta, Osun State, Southwestern, Nigeria" for consideration at PLOS Neglected Tropical Diseases. As with all papers reviewed by the journal, your manuscript was reviewed by members of the editorial board and by several independent reviewers. The reviewers appreciated the attention to an important topic. Based on the reviews, we are likely to accept this manuscript for publication, providing that you modify the manuscript according to the review recommendations.

I appreciate the work of the authors to respond to the concerns raised during the review process. The manuscript is much improved. However, a few important issues have not been adequately addressed; it will not be difficult for the authors to do so.

Please provide answers in the text to the following questions;

1. Why was this community chosen for the study? What kind of medical care service, if any, is available in the community? How many people live in the community? How were the 150 citizens chosen to participate in the survey?

2. Has the community been previously surveyed for the presence of onchocerciasis? If so, what was the prevalence? If not, why not? Presumably, ivermectin MDA has not been implemented there.

3. How close is the nearest community in which ivermectin MDA has been carried out? if MDA has not been carried out in the general vicinity, it may explain the lack of knowledge of the citizens.

I again thank the authors for their efforts to improve the manuscript and look forward to a second revision, which should enable the paper to proceed to publication.

Please prepare and submit your revised manuscript within 30 days. If you anticipate any delay, please let us know the expected resubmission date by replying to this email.

When you are ready to resubmit, please upload the following:

[1] A letter containing a detailed list of your responses to all review comments, and a description of the changes you have made in the manuscript.

Please note while forming your response, if your article is accepted, you may have the opportunity to make the peer review history publicly available. The record will include editor decision letters (with reviews) and your responses to reviewer comments. If eligible, we will contact you to opt in or out

[2] Two versions of the revised manuscript: one with either highlights or tracked changes denoting where the text has been changed; the other a clean version (uploaded as the manuscript file).

Important additional instructions are given below your reviewer comments.

Thank you again for your submission to our journal. We hope that our editorial process has been constructive so far, and we welcome your feedback at any time. Please don't hesitate to contact us if you have any questions or comments.

Sincerely,

Timothy G. Geary, PhD

Deputy Editor

PLOS Neglected Tropical Diseases

Timothy Geary

Deputy Editor

PLOS Neglected Tropical Diseases

***********************

I appreciate the work of the authors to respond to the concerns raised during the review process. The manuscript is much improved. However, a few important issues have not been adequately addressed; it will not be difficult for the authors to do so.

Please provide answers in the text to the following questions;

1. Why was this community chosen for the study? What kind of medical care service, if any, is available in the community? How many people live in the community? How were the 150 citizens chosen to participate in the survey?

2. Has the community been previously surveyed for the presence of onchocerciasis? If so, what was the prevalence? If not, why not? Presumably, ivermectin MDA has not been implemented there.

3. How close is the nearest community in which ivermectin MDA has been carried out? if MDA has not been carried out in the general vicinity, it may explain the lack of knowledge of the citizens.

I again thank the authors for their efforts to improve the manuscript and look forward to a second revision, which should enable the paper to proceed to publication.

Figure 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. 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 us at figures@plos.org.

Data Requirements:

Please note that, as a condition of publication, PLOS' data policy requires that you make available all data used to draw the conclusions outlined in your manuscript. Data must be deposited in an appropriate repository, included within the body of the manuscript, or uploaded as supporting information. This includes all numerical values that were used to generate graphs, histograms etc.. For an example see here: http://www.plosbiology.org/article/info%3Adoi%2F10.1371%2Fjournal.pbio.1001908#s5.

Reproducibility:

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References

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.

16 Feb 2022

Submitted filename: 1Response to reviewers.docx

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10 Mar 2022

Dear Mr Busari,

We are pleased to inform you that your manuscript 'Black flies and Onchocerciasis: Knowledge, attitude and practices among inhabitants of Alabameta, Osun State, Southwestern, Nigeria' has been provisionally accepted for publication in PLOS Neglected Tropical Diseases.

Before your manuscript can be formally accepted you will need to complete some formatting changes, which you will receive in a follow up email. A member of our team will be in touch with a set of requests.

Please note that your manuscript will not be scheduled for publication until you have made the required changes, so a swift response is appreciated.

IMPORTANT: The editorial review process is now complete. PLOS will only permit corrections to spelling, formatting or significant scientific errors from this point onwards. Requests for major changes, or any which affect the scientific understanding of your work, will cause delays to the publication date of your manuscript.

Should you, your institution's press office or the journal office choose to press release your paper, you will automatically be opted out of early publication. We ask that you notify us now if you or your institution is planning to press release the article. All press must be co-ordinated with PLOS.

Thank you again for supporting Open Access publishing; we are looking forward to publishing your work in PLOS Neglected Tropical Diseases.

Best regards,

Timothy G. Geary, PhD

Deputy Editor

PLOS Neglected Tropical Diseases

Timothy Geary

Deputy Editor

PLOS Neglected Tropical Diseases

***********************************************************

5 Apr 2022

Dear Mr Busari,

We are delighted to inform you that your manuscript, "Black flies and Onchocerciasis: Knowledge, attitude and practices among inhabitants of Alabameta, Osun State, Southwestern, Nigeria," has been formally accepted for publication in PLOS Neglected Tropical Diseases.

We have now passed your article onto the PLOS Production Department who will complete the rest of the publication process. All authors will receive a confirmation email upon publication.

The corresponding author will soon be receiving a typeset proof for review, to ensure errors have not been introduced during production. Please review the PDF proof of your manuscript carefully, as this is the last chance to correct any scientific or type-setting errors. Please note that major changes, or those which affect the scientific understanding of the work, will likely cause delays to the publication date of your manuscript. Note: Proofs for Front Matter articles (Editorial, Viewpoint, Symposium, Review, etc...) are generated on a different schedule and may not be made available as quickly.

Soon after your final files are uploaded, the early version of your manuscript will be published online unless you opted out of this process. The date of the early version will be your article's publication date. The final article will be published to the same URL, and all versions of the paper will be accessible to readers.

Thank you again for supporting open-access publishing; we are looking forward to publishing your work in PLOS Neglected Tropical Diseases.

Best regards,

Shaden Kamhawi

co-Editor-in-Chief

PLOS Neglected Tropical Diseases

Paul Brindley

co-Editor-in-Chief

PLOS Neglected Tropical Diseases