BACKGROUND & OBJECTIVES Phlebotomus argentipes is the vector for visceral leishmaniasis in India. The development of resistance in kala-azar vector to DDT has been reported from various parts of India. The main objective of this study was to generate information on insecticides susceptibility status of P. argentipes to DDT, malathion and deltamethrin in different parts in three states of India....

The prevalence of Trypanosoma cruzi infection in Triatoma infestans, Triatoma guasayana, and Triatoma sordida was evaluated in Amamá and other neighboring rural villages in northwestern Argentina for five years after massive spraying with deltamethrin in 1992 and selective sprays thereafter. Local residents and expert staff collected triatomines in domiciliary and peridomestic sites. During 199...

Fecundity and egg viability of Tribolium castaneum (Herbst) females were significantly (P<0.01) reduced by synthetic pyrethroids and an alkaloid containing insecticide nimbicidine. In control, the average number of eggs laid by each female/day was 12.18. The lowest number of eggs laid by each female/day was noted as 4.38 when combining nimbicidine with two pyrethroids i.e., cypermethrin and del...

Excitability changes following a nerve impulse were studied in the rat tail. Supernormal nerve excitability in control animals was present, as in other vertebrate nerve fibres, from 4-30 ms and was followed by a period of subnormal excitability extending up to 100-200 ms. Two to seven hours after intravenous administration of 1.5 mg/kg deltamethrin, supernormality was increased in degree and pr...

During the earlier stages of visceral leishmaniasis transmission in Posadas City, Misiones, both the night activity and attraction to humans of Lutzomyia longipalpis were assessed, in order to provide preliminary recommendations. The impact of peridomestic deltamethrin spraying performed by local officials was also evaluated. Although Lu. longipalpis were found in traps located over a dog the e...

A strain of Boophilus decoloratus, resistant to fenvalerate, was subjected to larval immersion, adult immersion and stall tests using the following classes of ixodicides: organochlorines, organophosphates, a diamidide and pyrethroids. A susceptible reference strain of B. decoloratus was used for comparative purposes. The results indicated a high level of resistance to DDT and camphechlor, sligh...

Mammalian voltage-gated Na(+) channels were less sensitive to pyrethroids than their insect counterparts by 2 to 3 orders of magnitude. Deltamethrin at 10 microM elicited weak gating changes in rat skeletal muscle alpha-subunit Na(+) channels (Nav1.4) after > 30 min of perfusion. About 10% of the peak current was maintained during the 8-ms, +50-mV pulse and, upon repolarization to -140 mV, the ...

Malaria in industrial complexes is promoted by extensive mosquitogenic potential generated by excavations and importation of parasite through migratory labor. The National Thermal Power Corporation (NTPC), Shaktinagar, Sonbhadra district was surveyed for malariogenic conditions from 1994 to 1996. The major mosquito breeding sites were drains, storm-water drains, lakes, outside tanks, overhead t...

Routine surveillance on resistant status of field mosquito populations is important to implement suitable strategies in order to prevent pest outbreaks. WHO test kit bioassay is the most frequent bioassay used to investigate the susceptibility status of field–collected mosquitoes, as it is relatively convenient to be carried out in the field. In contrast, the topical application of active ingre...

A 3-year entomological study was carried out on the transmission of malaria in a village of 900 inhabitants in a rice-growing area of Burkina Faso. In the study area inhabitants use bed nets to protect themselves from mosquito bites. In the first year of the study, baseline data were collected; in the second year, the village was divided in two parts and all the bed nets in the southern part we...