[K-othrine WG250 (deltamethrine)-based treatment in an area characterized by high infestation rates of Aedes aegypti].

Introduction: dengue and its lethal form, that is, dengue hemorrhagic fever, has significantly increased in Las Americas, being the Aedes aegypti the main and the only transmitting vector till now.

Objective: to evaluate the effectiveness of K-Othrine WG250 (deltamethrin) in residual (perifocal) applications in rest sites and in breeding sites of Aedes aegypti.

Methods: from February to June 2011, a perifocal residual treatment was applied in San Juan de Dios people's council of "José Martí" university polyclinic in Camaguey. It was directed to rest and breeding sites of the vector, for which several areas comprising different number of non-adjacent and randomly chosen houses, with high and similar rates of infestation in the period before the treatment, were selected. The application of this treatment was based on the use of IKA-9 hand sprayers at a dose of 1 g/l of water, with fitted conical nozzle for three areas and with flat nozzles 80-02 in the other three areas to deposit 25 mg ia/m2. Focality was monitored 5 months before the applications and 3 months afterwards by means of entomological surveys conducted in the selected universe of houses.

Results: the number of foci was reduced to 0 in the first month after the application if compared to the existing number before the treatment and with both types of nozzles. Fifteen positive reservoirs were reported in June, mainly low water tanks located outside the house.

Conclusions: this product showed high effectiveness for 3 months in the Aedes aegypti control as part of the residual (perifocal) treatment. Therefore, it should be considered as an alternative in the surveillance and control strategies aimed at this vector.