Efficacy of permethrin-impregnated clothing on knock-down and mortality of dengue mosquito vectors
2015 (English)In: Tropical medicine & international health, ISSN 1360-2276, E-ISSN 1365-3156, Vol. 20, no Suppl. 1, 110-110 p.Article in journal, Meeting abstract (Other academic) Published
Introduction: As vector control for dengue has proven to be elusive, additional methods to protect against dengue are urgently needed. We have previously shown that pre-fabricated clothing impregnated with permethrin in a proprietary manner had a close to 100% 1 h knock-down and 24 h-mortality effect on Aedes mosquito vectors. However, this effect rapidly declined with repeated washing. Here we investigated different impregnation techniques to assess the best method with the lowest waning efﬁcacy after washing. Materials and methods School clothes were impregnated with permethrin by two different technologies: pad-dry-cure versus exhaustion. Impregnated products were tested for their efﬁcacy using laboratory-reared Aedes mosquito vectors using WHOPES cone test, before and after 10 washes.
Results: The 1 h knock down effect and 24 h mortality rate of school clothes treated by both technologies were both found to be 100%. However, the clothes treated by pad-dry-cure technology could stand frequent washing better than those treated by exhaustion technology. The decrease in efﬁcacy of up to about 60% of the clothes treated by pad-dry-cure technology was observed after washing 8 times while those treated by exhaustion technology showed decrease in knock-down effect (67.27%) and mortality rate (74.29%) after washing only 4 times.
Conclusion: The knock-down and 24 h mortality results look very promising to support impregnated clothing as a potential strategy to protect against day-biting Aedes mosquito vectors to prevent dengue infections. However, rapid waning efﬁcacy of impregnated clothing after <10 washes suggests that impregnation techniques for sustainable effect are sub-optimal and hence such an approach is not recommended at this point in time. Either new impregnation technologies will need to be developed to overcome the waning efﬁcacy after washing, or clothing such as aprons or vests will need to be employed. Since school aprons are hanged in classrooms after daily use without washing through out the school term, they could potentially have a prolonged impact of permethrin on mosquito vectors (in terms of knock-down and mortality) and eventually dengue transmission in school.
This research was funded by the European Union 7th Frame- work Programme through ‘DengueTools’ and Mahidol University.
Disclosure: Nothing to disclose
Place, publisher, year, edition, pages
Wiley-Blackwell, 2015. Vol. 20, no Suppl. 1, 110-110 p.
Public Health, Global Health, Social Medicine and Epidemiology
IdentifiersURN: urn:nbn:se:umu:diva-109941ISI: 000360758800267OAI: oai:DiVA.org:umu-109941DiVA: diva2:861305
The 9th European Congress on Tropical Medicine and International Health, (ECTMIH), Basel, Switzerland, September 6-10, 2015