Data from: A low technology emanator treated with the volatile pyrethroid transfluthrin confers long term protection against outdoor biting vectors of lymphatic filariasis, arboviruses and malaria

Background. The vapor phase of the volatile pyrethroid transfluthrin
incapacitates mosquitoes and prevents them from feeding. Although existing
emanator products for delivering volatile pyrethroids protect against
outdoor mosquito bites, they are too short-lived to be practical or
affordable for routine use in low-income settings. New transfluthrin
emanators, comprised simply of treated hessian fabric strips, have
recently proven highly protective against outdoor-biting vectors of
lymphatic filariasis, arboviruses and malaria, but their full protective
lifespan, minimum dose requirements, and range of protection have not
previously been assessed. Methodology. The effects of
transfluthrin-treated hessian strips upon mosquito biting exposure of
users and nearby non-users, as well as dependence of protection upon
treatment dose, were measured outdoors in rural Tanzania using human
landing catches (HLC). Principal Findings. Strips treated with 10ml of
transfluthrin prevented at least three quarters (p < 0.001) of
outdoor bites by Anopheles arabiensis, Culex spp. and Mansonia spp.
mosquitoes, and >90% protection against bites on warmer nights with
higher evaporation rates, for at least one year. Strips treated with this
high dose also reduced biting exposure of non-users at a distance of up to
5m from the strips for An. arabiensis (p < 0.001) and up to 2m for
Mansonia spp. (p = 0.008), but provided no protection to non-users against
Culex spp.. No evidence of increased risk for non-users, caused by
diversion of mosquitoes to unprotected individuals, was found at any
distance within an 80m radius. A dose of only 1ml provided equivalent
protection to the 10ml dose against An. arabiensis, Culex spp. and
Mansonia spp. mosquitoes over 6 months (p < 0.001).
Conclusions/Significance. Transfluthrin-treated hessian emanators provide
safe, affordable, long-term protection against several different
pathogen-transmitting mosquito taxa that attack humans outdoors, where
they are usually active and cannot be protected by bed nets or residual
sprays with conventional, solid-phase insecticides.