El uso de Sistemas de Información Geográfica - CDIA-EC ...

El uso de Sistemas de Información Geografica y Sensores Remotos (SR) en Salud Pública
Bogotá, Colombia, 27 al 30 de Marzo de 2006
triatomines and it can help to identify the specific characteristics of houses that
should be prioritized in house improvement programmes.
The results from two risk factor analysis are presented here: 1) from a controlled
research study carried in Barinas (South-Western Venezuela) and 2) from an
unusually large survey carried out by a team of four Colombian institutions in
conjunction with Ministry of Health Personnel.
A multivariate logistic regression was undertaken to identify risk factors (35
measured at house level and 18 at outbuilding level) for indoor triatomine
infestation and colonisation in 18 villages (552 houses and 1,068 peridomestic
outbuildings) in Barinas State, Venezuela. All houses and peridomestic outbuildings
were inspected by active search aided with tetramethrin and by householders, who
were urged to keep any triatomines found. After adjusting for other risk factors,
including palm roofs and the presence of hen nests, R. prolixus infestation and
colonisation of outbuildings (and, to some extent, houses) was significantly
associated with proximity to high densities of Attalea butyracea palm trees. House
infestation was also positively associated with bug density in peridomestic
outbuildings, the age of the palm roof, the presence of pigsties and hen nests. The
presence of cement walls and electricity resulted protective factors for infestation
and colonization with R. prolixus respectively. House infestation and colonization
with Triatoma maculata was significantly enhanced in houses with hen nests
present. Amongst peridomestic outbuildings with nests, the highest risks of
infestation and colonization were in outbuildings with a palm roof.
In Colombia the association between triatomine infestation and housing
characteristics was investigated based on an unusually large standardized survey
in 41,971 houses in 15 departments. Multivariate logistic regression was used to
test for associations of two highly correlated infestation measures of infestation
(householders reporting having seen triatomines inside the house, and sending
triatomines to the survey team), with 15 household level risk factors. Residents
were asked if they had seen triatomines and were handed posts to collect any
triatomine they would find. The results from house-level risk factor analysis in
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