Behavior of Lutzomyia longipalpis, the main vector of American visceral leishmaniasis, in Campo Grande, State of Mato Grosso do Sul

摘要

The municipality of Campo Grande, State of Mato Grosso do Sul, Brazil, has presented cases of canine and human visceral leishmaniasis since 2002, and is classified as an area of intense transmission. This study was carried out from May 2003 to April 2005, in partnership with the National Health Foundation and the State Health Department, with the objective of determining the behavior and seasonality of the species Lutzomyia longipalpis. Captures were accomplished using luminous traps of CDC type, at twelve stations distributed in the urban zone. The stations with the highest population densities were situated in the southern part of the city and the relative abundance increased during or immediately after rainfall. During the cold and dry months, the number of specimens was reduced and the relative abundance was higher in habitats surrounding homes. Spraying with alpha-cypermethrin at four-month intervals contributed towards reducing the vector numbers in three of the four sprayed stations. Among the eight stations that did not receive chemical interventions, five showed an increase.