New classification of natural breeding habitats for Neotropical anophelines in the Yanomami Indian Reserve, Amazon Region, Brazil and a new larval sampling methodology

Here we present the first in a series of articles about the ecology of immature stages of anophelines in the Brazilian Yanomami area. We propose a new larval habitat classification and a new larval sampling methodology. We also report some preliminary results illustrating the applicability of the methodology based on data collected in the Brazilian Amazon rainforest in a longitudinal study of two remote Yanomami communities, Parafuri and Toototobi. In these areas, we mapped and classified 112 natural breeding habitats located in low-order river systems based on their association with river flood pulses, seasonality and exposure to sun. Our classification rendered seven types of larval habitats: lakes associated with the river, which are subdivided into oxbow lakes and nonoxbow lakes, flooded areas associated with the river, flooded areas not associated with the river, rainfall pools, small forest streams, medium forest streams and rivers. The methodology for larval sampling was based on the accurate quantification of the effective breeding area, taking into account the area of the perimeter and subtypes of microenvironments present per larval habitat type using a laser range finder and a small portable inflatable boat. The new classification and new sampling methodology proposed herein may be useful in vector control programs.

Avaliaçäo da eficacia de dois larvicidas biologicos no controle de mosquitos no Distrito Federal / Assessment of the Efficacy of Two Biological Larvicides in Mosquito Control in Distrito Federal

A eficacia de dois inseticidas biologicos a base de Bacillus sphaericus e Bacillus thuringiensis foi comparada a do inseticida quimico Abate, um organofosforado a base de Temefos, utilizado sistematicamente no controle de mosquitos na area urbana de Brasilia. O trabalho foi realizado pelo Nucleo de Controle de Vetores do Instituto de Saude do Distrito Federal em cooperacao com o Centro Nacional de Pesquisa de Recursos Geneticos e Biotecnologia (CENARGEN). Os tres produtos apresentaram resultados satisfatorios, reduzindo a densidade de larvas nos criadouros. Entretanto, no decimo quinto dia de avaliacao do experimento, os criadouros tratados com B. sphaericus continuavam apresentando baixo numero de larvas, indicando persistir mais tempo que os outros dois produtos (Au);