Dengue outbreaks in Divinopolis, south-eastern Brazil and the geographic and climatic distribution of Aedes albopictus and Aedes aegypti in 2011-2012

Trop Med Int Health. 2015 Jan;20(1):77-88. doi: 10.1111/tmi.12402. Epub 2014 Oct 20.

Abstract

Objective: To entomologically monitor Aedes spp. and correlate the presence of these vectors with the recent epidemic of dengue in Divinopolis, Minas Gerais State, Brazil.

Methods: Ovitraps were installed at 44 points in the city, covering six urban areas, from May 2011 to May 2012. After collection, the eggs were incubated until hatching. In the 4th stage of development, the larvae were classified as Ae. aegypti or Ae. albopictus.

Results: In total, 25 633 Aedes spp. eggs were collected. February was the month with the highest incidence, with 5635 eggs collected and a hatching rate of 46.7%. Ae. aegypti eggs had the highest hatching rate, at 72.3%, whereas Ae. albopictus eggs had 27.7%. Climate and population density influenced the number of eggs found. Indicators of vector presence were positively correlated with the occurrence of dengue cases.

Conclusion: These data reinforce the need for entomological studies, highlight the relevance of Ae. albopictus as a possible disease vector and demonstrate its adaptation. Ae. albopictus, most commonly found in forested areas, comprised a substantial proportion of the urban mosquito population.

Keywords: Aedes aegypti; Aedes albopictus; dengue; entomological index; indice entomologique; ovitrampas; ovitraps; pièges à œufs; índice entomológico.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aedes / growth & development*
  • Animals
  • Brazil / epidemiology
  • Dengue / epidemiology
  • Dengue / transmission*
  • Disease Outbreaks
  • Entomology
  • Humans
  • Insect Vectors / growth & development*
  • Larva / growth & development
  • Seasons
  • Temperature
  • Urban Health