Safety of a topical insect repellent (picaridin) during community mass use for malaria control in rural Cambodia

Abstract

BackgroundWhile community distribution of topical repellents has been proposed as an additional malaria control intervention, the safety of this intervention at the population level remains poorly evaluated. We describe the safety of mass distribution of the picaridin repellent during a cluster-randomised trial in rural Cambodia in 2012–2013.MethodsThe repellent was distributed among 57 intervention villages with around 25,000 inhabitants by a team of village distributors. Information on individual adverse events, reported by phone by the village distributors, was obtained through home visits. Information on perceived side effects, reported at the family level, was obtained during two-weekly bottle exchange. Adverse events were classified as adverse reactions (events likely linked to the repellent), cases of repellent abuse and events not related to the repellent use, and classified as per Common Terminology Criteria for Adverse Events.FindingsOf the 41 adverse events notified by phone by the village distributors, there were 22 adverse reactions, 11 cases of repellent abuse (6 accidental, 5 suicide attempts) and 8 non-related events. All adverse reactions were mild, occurred in the first few months of use, and mainly manifested as skin conditions. Of the 11 cases of abuse, 2 were moderate and 2 life-threatening. All cases with adverse reactions and repellent abuse recovered completely. 20% of families reported perceived side effects, mainly itching, headache, dizziness and bad smell, but few discontinued repellent use.ConclusionsAdverse reactions and abuse during mass use of picaridin were uncommon and generally mild, supporting the safety of the picaridin repellent for malaria control.

Evaluation of a push–pull system consisting of transfluthrin-treated eave ribbons and odour-baited traps for control of indoor- and outdoor-biting malaria vectors

“…Spatial repellents and odour baited traps have both separately been proposed as potential new tools for expanding the malaria control tool box, though there is not yet adequate data to justify their large-scale application [ 9 ]. For spatial repellents, current focus areas include developing strategies for delivery of active ingredients in ways that ensure long-term efficacy and safety [ 34 ] and also improving user compliance, which has previously impaired field effectiveness [ 17 ]. On the other hand, for odour-baited traps, focus areas include developing highly effective attractants [ 23 ] and improved trapping devices [ 23 ], but also on how the technologies can best be combined with existing interventions [ 28 , 31 ].…”

“…Even where repellents offer effective protection, poor compliance among users can significantly reduce this protection [ 7 , 8 ]. This is particularly a challenge with topical repellents, such as picaridin, for which despite high reported acceptance, actual daily user compliance was as low as 8% in a trial in Cambodia [ 8 , 17 ]. Because of the sub-optimal use even in areas with high access rates, the repellents in this study did not lead to any further reduction in malaria burden [ 18 ].…”

Wilderness Medical Society Clinical Practice Guidelines for the Prevention and Management of Tick-Borne Illness in the United States

“…Although picaridin has a much shorter track record of use than DEET, it appears to be nontoxic and, when compared to DEET, has a superior safety profile. 42 Picaridin is also odorless and, in contrast to DEET, is not harmful to synthetic fabrics.…”

Characterization in Effective Stimulation on the Magnitude, Gating, Frequency Dependence, and Hysteresis of INa Exerted by Picaridin (or Icaridin), a Known Insect Repellent

“…Picaridin (icaridine, 1-piperidinecarboxylic acid 2-(2-hydroxyethyl)-1-methylpropylester), a cyclic amine and a member of the piperidine chemical family, is viewed as a synthetic, broad-spectrum arthropod repellent [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 ]. The repellent and deterrent activities of picaridin have been previously demonstrated to involve olfactory sensing in mosquitoes and ticks, via their interactions with odorant receptor proteins residing in neurons [ 17 , 18 , 19 , 20 , 21 , 22 ].…”