Seasonal abundance of Lutzomyia longipalpis (Diptera: Psychodidae) at an endemic focus of visceral leishmaniasis in Colombia.
Ecological studies on the sand fly Lutzomyia longipalpis (Lutz & Neiva) were conducted during 1990-1993 in a small rural community in Colombia where American visceral leishmaniasis is endemic. Standardized weekly sand fly collections made from pigpens and natural resting sites displayed a bimodal annual abundance cycle, with a small peak occurring in October-November and a larger one in April-May. Time series analysis was employed to quantify the associations between sand fly abundance and weather factors (temperature, relative humidity, and rainfall). In addition to a prominent 6-mo cycle. Fourier analysis of the collection data demonstrated that the L. longipalpis population also exhibited a 5- to 8-wk cycle that may represent the length of larval development. Autoregressive moving average models were fit to weekly collection data and their residuals were regressed against rainfall, temperature, and relative humidity. A significant positive association between female L. longipalpis abundance and the relative humidity and rainfall recorded 3 wk earlier was found, indicating that these factors may be of value in predicting sand fly abundance. Additionally, these data indicated that L. longipalpis larvae may become quiescent during adverse conditions.
Morrison
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AC
Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, CT 06520-8034, USA.
Ferro
C
C
Pardo
R
R
Torres
M
M
Devlin
B
B
Wilson
M L
ML
Tesh
R B
RB
D000818:Animals; D003105:Colombia / Q000453:epidemiology; D003624:Darkness; D005260:Female; D007898:Leishmaniasis, Visceral / Q000453:epidemiology / Q000469:parasitology*; D008027:Light; D008297:Male; D008685:Meteorological Concepts; D011157:Population Dynamics; D011576:Psychodidae / Q000502:physiology*; D012621:Seasons