Testing Insect Repellents Against Musca Sorbens, the Vector of Trachoma (NCT03813069) | Clinical Trial Compass
CompletedPhase 2
Testing Insect Repellents Against Musca Sorbens, the Vector of Trachoma
Ethiopia, United Kingdom64 participantsStarted 2019-01-10
Plain-language summary
Musca sorbens, a fly that feeds from ocular and nasal discharge on humans, is thought to be the vector of trachoma. We are developing methods of fly control that specifically target this species, in the hope of interrupting Ct transmission. To our knowledge, the use of commercially available insect repellents has never been tested for prevention of Musca sorbens fly-eye contact (i.e. nuisance and landing in the peri-ocular area). Given the likely necessity for prolonged and/or high frequency fly-eye contact for Ct transmission, the reduction of these contacts through the use of fly repellents presents an exciting opportunity for disease control. Here we propose a within-subject, non-masked, trial of the use of commercially available insect repellents against Musca sorbens, with two consecutive participant groups in the laboratory and in the field, and a primary endpoint of measuring the protective efficacy of each repellent product. Repellent products will be chosen from: DEET (N,N-diethyl-3-methylbenzamide), IR3535 (3-\[N-butyl-N-acetyl\]-aminopropionic acid ethyl ester), Picaridin (2-(2-hydroxyethyl)-1-piperidinecarboxylic acid 1-methylpropyl ester); PMD (para-Menthane-3,8-diol) or permethrin (m-Phenoxybenzyl)-cis,trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate). Products tested will be either (1) topical repellents, or (2) in long-lasting, plastic formulations of repellents that can be worn on the body (wearable repellent technologies). The insect repellent synergist Vanillin (4-Hydroxy-3-methoxybenzaldehyde) may be added to the long-lasting plastic formulations, to improve the duration of protection.
Who can participate
Age range
3 Years – 65 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Laboratory trial eligibility criteria
1. Participant is aged \> 18 years and \< 65 years and in good health
2. Participant has a good understanding of the procedures of the study and agrees to abide to these procedures
3. Participant is able to communicate well with the investigator, and attend the laboratory for all aspects of the laboratory studies
4. Participant has no known adverse reactions, or evidence at screening of adverse reactions, to the commercially available repellents DEET, PMD, IR3535, Picaridin or Permethrin, or to Vanilla
5. Participant has no known history of skin allergies or hypersensitivity to topical creams
6. Participant agrees to a pre-trial skin reactivity test for all the repellents that will be used in the trial
7. If in the event of the participant experiencing an adverse reaction to a repellent during the trial, the participant agrees to inform his/her general practitioner and seek appropriate treatment if necessary
8. Participant is willing to allow laboratory-reared Musca sorbens flies to land and crawl on their arm, during the modified arm-in-cage assay, for periods of up to ten minutes at a time
9. Participant agrees not to use any perfumed or scented product, including bathing products, for a 24-hour period before each laboratory session
10. Participant has signed informed consent
11. Participant is not a smoker, and will agree to refraining from smoking for the 12 hours before each laboratory trial
Field trial eligibility criteria
1. Par…
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Protective Efficacy (PE)
Timeframe: 2 months
2
Complete Protection Time (CPT)
Timeframe: 3 months
Trial details
NCT IDNCT03813069
SponsorLondon School of Hygiene and Tropical Medicine