Impact of environmental temperatures on resistance to organophosphate insecticides in Aedes aegypti from Trinidad.
نویسندگان
چکیده
OBJECTIVE To examine the effects of increasing larval rearing temperatures on the resistance status of Trinidadian populations of Aedes aegypti to organophosphate (OP) insecticides. METHODS In 2007-2008, bioassays and biochemical assays were conducted on A. aegypti larvae collected in 2006 from eight geographically distinct areas in Trinidad (Trinidad and Tobago). Larval populations were reared at four temperatures (28 ± 2ºC, 32ºC, 34ºC, and 36ºC) prior to bioassays with OP insecticides (fenthion, malathion, and temephos) and biochemical assays for esterase enzymes. RESULTS Most larval populations reared at 28 ± 2ºC were susceptible to fenthion (>98% mortality) but resistant to malathion and temephos (< 80% mortality). A positive association was found between resistance to OP insecticides and increased activities of α- and β-esterases in larval populations reared at 28 ± 2ºC. Although larval populations reared at higher temperatures showed variations in resistance to OPs, there was a general increase in susceptibility. However, increases or decreases in activity levels of enzymes did not always correspond with an increase or decrease in the proportion of resistant individuals reared at higher temperatures. CONCLUSIONS Although global warming may cause an increase in dengue transmission, based on the current results, the use of insecticides for dengue prevention and control may yet be effective if temperatures increase as projected.
منابع مشابه
Climate change, environmental temperature change, and resistance to insecticides of dengue mosquito.
To the Editor: The recent article, “Impact of environmental temperatures on resistance to organophosphate insecticides in Aedes aegypti from Trinidad,” is very interesting (1). Polson and colleagues simulated temperature change as a model of global warming and concluded that “the use of insecticides for dengue prevention and control may yet be effective if temperatures increase as projected” (1...
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عنوان ژورنال:
- Revista panamericana de salud publica = Pan American journal of public health
دوره 32 1 شماره
صفحات -
تاریخ انتشار 2012