Characteristics of the Spatial Pattern of the Dengue Vector, Aedes aegypti, in Iquitos, Peru
We determine the spatial pattern of Aedes aegypti and the containers in which they develop in two neighborhoods of the Amazonian city of Iquitos, Peru. Four variables were examined: adult Ae. aegypti, pupae, containers positive for larvae or pupae, and all water-holding containers. Adults clustered strongly within houses and weakly to a distance of 30 m beyond the household; clustering was not detected beyond 10 m for positive containers or pupae. Over short periods of time restricted flight range and frequent blood-feeding behavior of Ae. aegypti appear to be underlying factors in the clustering patterns of human dengue infections. Permanent, consistently infested containers (key premises) were not major producers of Ae. aegypti, indicating that larvaciding strategies by themselves may be less effective than reduction of mosquito development sites by source reduction and education campaigns. We conclude that entomologic risk of human dengue infection should be assessed at the household level at frequent time intervals.
KeywordsAdult Mosquito Dengue Case Complete Spatial Randomness Dengue Transmission Entomologic Survey
We thank the residents of Maynas and Tupac Amaru, Iquitos, Peru for allowing us to work with them in their homes. We greatly appreciate support of the Loreto Regional Health Department, including Dr. Carlos Calampa, Dr. Jorge Reyes, Dr. Ruben Naupay, Dr. Carlos Vidal, Dr. Martin Casapia, and Dr. Moises Sihuincha, who have all facilitated our work in Iquitos. Helvio Astete and Gerson Perez Rodriguez supervised the collection and processing of mosquitoes. Entomologic surveys were carried out by Jimmy Maykol Castillo Pizango, Rusbel Inapi Tamani, Juan Luiz Sifuentes Rios, Nestor Jose Nonato Lancha, Federico Reategui Viena, Victor Elespuru Hidalgo, Edson Pilco Mermao, Abner Enrique Varzallo Lachi, Fernando Chota Ruiz, Angel Puertas Lozano, Guillermo Inapi Huaman, and Manuel Ruiz Rioja. Jimmy Roberto Espinoza Benevides and Fernando Espinoza Benevides entered data into our database. Jose Elespuro Bastos checked data entry for accuracy.
Financial support: This study was supported by grant AI-42332 from the National Institutes of Health.
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