The use of bacterial larvicides in mosquite and black fly control programmes in Brazil

Bacillus spp. based larvicides are increasingly replacing, with numerous advantages, chemical insecticides in programmes for controlling black fly and mosquito populations. Brazil was among the pioneers in adopting Bacillus thuringiensis israelensis (B.t.i) to control black flies. However, the major current mosquito control programme in Brazil, the Programme for Eradication of Aedes aegypti launched in 1997, only recently decided to replace temephos by B.t.i based larvicides, in the State of Rio de Janeiro. In the last decade, works developed by research groups in Brazilian institutions have generated a significant contribution to this subject through the isolation of B. sphaericus new strains, the development of new products and the implementation of field trials of Bacillus efficacy against mosquito species under different environmental conditions

Controle integrado do vetor da filariose com participaçäo comunitária, em uma área urbana do Recife, Brasil / Integrated control of the filariasis vector with community participation in an urban area of Recife, Pernambuco, Brazil

Um projeto piloto para o controle da filariose bancroftiana foi desenvolvido em duas áreas do Recife, com índices iniciais de prevalência de microfilaremia de 10 por cento. Nas duas áreas, foi aplicado um tratamento em massa com doses baixas de dietilcarbamazina. Em uma das áreas, esse tratamento foi associado ao controle do vetor, integrando medidas físicas, como o uso de camadas flutuantes de esferas de poliestireno, ao tratamento periódico dos criadouros com a bactéria entomopatógena Bacillus sphaericus. Como resultado, a densidade populacional do vetor, de ordem de sessenta a 120 Culex/quarto/noite antes das intervençöes, foi drasticamente reduzida, mantendo-se, durante dois anos, em valores entre quatro e 16 Culex/quarto/noite. Neste contexto, as açöes para envolver a comunidade escolar local no controle do vetor resultaram na realizaçäo de atividades curriculares e extraclasses, culminando com a participaçäo efetiva de grupos de alunos ("Vigilantes de vetores") na aplicaçäo das medidas de controle e na divulgaçäo de conhecimentos básicos sobre a biologia do Culex quinquefasciatus. O entusiástico envolvimento de professores e alunos mostrou ser a escola um espaço aberto à participaçäo em programas desta natureza.

Integrated control measures against Culex quinquefasciatus, the vector of filariasis in Recife

Integrated control measures against Culex quinquefasciastus have been implemented in a pilot urban area in Recife, Brazil. About 3,000 breeding sites found within the operational area were responsible for very high mosquito densities recorded during the pretrial period. Physical control measures have been applied to cess pits before starting a series of 37 treatments of the other sites with Bacillus sphaericus strain 2362, over 27 months. In spite of the difficulties due to environmental conditions, very significant reductions in preimaginal population of C. quinquefasciatus were achieved and, as a consequence, low adult mosquito densities were maintained for a relatively long period of time. Entomological and environmental data gathered in this pilot project can contribute to design an integrated mosquito control program in Recife city.