Effects of climate and different management strategies on Aedes aegypti breeding sites: a longitudinal survey in Brasília (DF, Brazil)

• Published in: Tropical medicine & international health 2006-07, Vol.11 (7), p.1104-1118
• Main Authors: Favier, Charly, Degallier, Nicolas, Ribeiro Vilarinhos, Paulo de Tarso, De Carvalho, Maria do Socorro Laurentino, Cavalcanti Yoshizawa, Maria Amelia, Britto Knox, Monique
• Format: Article
• Language: English
• Subjects: Aedes - physiology; Aedes aegypti; Animal reproduction; Animals; Brazil; Climate; Dengue - prevention & control; Disease management; Disease transmission; Earth Sciences; Environment; Environmental Sciences; Geophysics; Global Changes; Health Surveys; Humans; Insect Vectors - physiology; Insecticides; Larva - physiology; Longitudinal Studies; Mosquitoes; Physics; Polls & surveys; Risk Factors; Sciences of the Universe; Seasons; Water Supply; Yellow Fever - prevention & control
• ISSN: 1360-2276; 1365-3156
• DOI: 10.1111/j.1365-3156.2006.01653.x

Summary Objective  To determine the influence of climate and of environmental vector control with or without insecticide on Aedes aegypti larval indices and pupae density. Methods  An 18‐month longitudinal survey of infestation of Ae. aegypti immature stages was conducted for the 1015 residences (premises) of Vila Planalto, an area of Brasilia where the Breteau Index was about 40 before the study. This area was divided into five zones: a control zone with environmental management alone and four zones with insecticide treatment (methoprene, Bti, temephos). We tested for significant differences between infestation levels in the control and insecticide‐treated areas, for relationships between climatic variables and larval indices, and to determine risk factors of infestation for certain types of premises and containers. Results  Environmental vector control strategies dramatically decreased infestation in the five areas. No significant differences could be detected between control strategies with insecticide and without. Some premises and container types were particularly suitable for breeding. The influence of climate on the emergence of Ae. aegypti adults for the area is described. Conclusion  In a moderately infested area such as Brasilia, insecticides do not improve environmental vector control. Rather, infestations could be further reduced by focusing on residences and containers particularly at risk. The nature of the link between climate and larval population should be investigated in larger‐scale studies before being used in forecasting models. Keywords  Aedes aegypti management strategies longitudinal survey breeding sites larval Stegomyia indices pupae Objectifs  Déterminer l'influence du climat et du contrôle environnemental des vecteurs avec ou sans insecticide sur les indices larvaires d’Aedes aegypti et sur la densité des nymphes. Méthodes  Une surveillance longitudinale sur 18 mois de l'infestation par les stades immatures d’Ae. aegypti a été conduite sur les 1015 résidences de Vila Planalto, un quartier de Brasília où l'indice de Breteau était d'environ 40 avant l’étude. Ce quartier a été divisé en 5 zones: une zone témoin avec une gestion environnementale seule et 4 zones avec des traitements par insecticide (methoprene, Bti, temephos). Nous avons recherché: 1) des différences significatives entre les niveaux d'infestation de la zone témoin et les zones traitées aux insecticides; 2) des relations entre les paramètres climatiques et les indice