Ecology of Lutzomyia longipalpis in an area of visceral leishmaniasis transmission in north-eastern Brazil.
Visceral leishmaniasis is a major public health issue in South America, where the disease is rapidly spreading. Changes in ecology and distribution of the principal vector, Lutzomyia longipalpis are among the factors accounting for the increasing incidence of the disease in this region. However, information about the ecology of L. longipalpis is still incipient, which may directly impair the implementation of effective control programs. Herein, the ecology of L. longipalpis was studied in a focus of visceral leishmaniasis in north-eastern Brazil. From August 2009 to August 2010, phlebotomine sand flies were monthly collected in four localities using CDC light traps (~37 per month) and a lantern-baited Shannon trap with mouth aspirators. A total of 24,226 phlebotomine sand flies were collected with light traps and 375 with mouth aspirators. The most abundant species was L. longipalpis, representing 97.9% of the specimens collected with light traps and 91.5% with the mouth aspirator. Other species (Lutzomyia evandroi, Lutzomyia lenti and Lutzomyia sallesi) were found in low numbers. Most phlebotomine sand flies (94.6%) were collected at chicken coops and corrals. No significant correlation was found between the monthly abundance of phlebotomine sand flies and the monthly averages of temperature, relative humidity or rainfall. However, interestingly enough, 82.4% of L. longipalpis specimens were collected in months when relative humidity surpassed 75%. This study points out that this vector is well adapted to live in different habitats and to different climate conditions. It also suggests that some north-eastern populations of L. longipalpis may be more xerotolerant than southern populations. Further studies to assess the relationship between microclimate and L. longipalpis density in different Brazilian regions are advised.
Departamento de Imunologia, Centro de Pesquisas Aggeu Magalhães, Fundação Oswaldo Cruz, Recife, Pernambuco, Brazil.
Pietra Lemos
PL
Costa
Filipe
F
Dantas-Torres
Fernando José
FJ
da Silva
Vanessa Cristina Fitipaldi Veloso
VC
Guimarães
Kamila
K
Gaudêncio
Sinval Pinto
SP
Brandão-Filho
D000818:Animals; D001938:Brazil / Q000453:epidemiology; D004463:Ecology; D017753:Ecosystem; D005260:Female; D006801:Humans; D006813:Humidity; D007303:Insect Vectors / Q000145:classification / Q000502:physiology*; D018314:Leishmania infantum / Q000502:physiology; D007898:Leishmaniasis, Visceral / Q000453:epidemiology / Q000469:parasitology / Q000635:transmission*; D008297:Male; D011156:Population Density; D011576:Psychodidae / Q000145:classification / Q000502:physiology*; D011891:Rain; D012621:Seasons; D013696:Temperature