Emergence of Aedes albopictus in artificial containers

Author(s)

Oswaldo Paulo Forattini ^[1] ; Iná Kakitani ^[2] ; Helene Mariko Ueno ^[3]

Affiliation

^[1] Universidade de São Paulo. Faculdade de Saúde Pública. Departamento de Epidemiologia - Brasil

^[2] Universidade de São Paulo. Faculdade de Saúde Pública. Departamento de Epidemiologia - Brasil

^[3] Universidade de São Paulo. Faculdade de Saúde Pública. Departamento de Epidemiologia - Brasil

• Document type: Journal article
• Source: Revista de Saúde Pública; v. 35, n. 5, p. 456-460, 2001-10-00.

Abstract

OBJECTIVE: To estimate the potential of daily average emergence of Aedes albopictus adult females. Since this species is very close to Aedes aegypti , although it has not been implicated in the spread of dengue in Brazil. METHODS: Observations were carried out fortnightly and incessantly in Pedrinhas, in the state of São Paulo, Brazil, between 1996 and 2000. Breeding productivity was measured using the emergence index (E). Two large reservoirs of more than 10 liters of water were used, and their permanent character was assured by replacing water every time its level was low. The other reservoirs were six pots, initially filled out with a liter of distilled water. The water content was constantly replaced after every collection, regardless of rainfall. The associations with climatic factors were calculated using the correlation index of Pearson. RESULTS: The emergence (E) in the uncovered reservoir was 66.5, much higher than the one found at the covered water tank, which was 12.2. The permanent character of both breeding settings was assured by water replacement when there was a decrease in the water levels. There was no significant association between rainfall and temperature variations. It was observed in some of the six pots an association between rainfall and the emergence index, with a lesser productivity in the months with lower rainfalls. That period, June to November, would be the most propitious time to perform the mechanical removal of the containers. CONCLUSION: The differences in productivity of the two permanent reservoirs could be explained, at least in part, to the existence of organic matter that allows larval growth. Regarding the temporary containers, it seems that the best time for cleaning up would be during the dry months. Having organic matter in the water of breeding settings could enable the isolation of these two mosquito populations, Aedes aegypti and Aedes albopictus. (AU)

• FAPESP's process: 99/10517-1 - Synanthropic studies about Culicidae mosquitoes
• Grantee: Oswaldo Paulo Forattini
• Support Opportunities: Research Projects - Thematic Grants