Author/Authors :
Azizi، Kourosh نويسنده 1. Department of Medical Entomology, Research Center for Health Sciences, Faculty of Health & Nutrition, Shiraz University of Medical Sciences, Shiraz Azizi, Kourosh , Moemenbellah-Fard، Mohammad Djaefar نويسنده Department of Medical Entomology, Research Center for Health Sciences, School of Health and Nutrition, Shiraz University of Medical Sciences, Shiraz, , , Khosravani-Shiri، Mousa نويسنده Department of Medical Entomology and Vector Control, School of Health, Shiraz University of Medical Sciences, Shiraz, Iran Khosravani-Shiri, Mousa , Fakoorziba، Mohammad Reza نويسنده Department of Medical Entomology and Vector Control, Research Center for Health Sciences, Faculty of Health and Nutrition, Shiraz University of Med Fakoorziba, Mohammad Reza , Soltani ، Aboozar نويسنده Department of Medical Entomology and Vector Control, School of Public Health and National Institute of Health Research, Tehran University of Medical Sciences, Tehran, Iran ,
Abstract :
Background: Human malaria remains a major malady in Eastern
Iran. Vector control interventions such as indoor residual spraying
are used to fight with the disease. This study was undertaken
to determine the lethal and residual effects of three different
pyrethroid insecticides on adult mosquitoes of Anopheles
stephensi on different surfaces in Iran, as part of a national
program to monitor insecticide resistance in endemic areas.
Methods: Two main endemic foci were selected as collection
sites. Wild adult females of An. stephensi (mysoriensis strain)
from the first focus were subjected to standard susceptibility
tests, using lambdacyhalothrin, deltamethrin and cyfluthrin
insecticides within holding tubes according to the method
proposed by WHO. In Kazerun, the residual effects of these
compounds were examined by conical bioassay tests of An.
stephensi (type strain) on plaster and cement walls. Data were
analyzed using Mann-Whitney test to determine the differences
in susceptibility and residual effects of An. stephensi mosquitoes
to these insecticides.
Results: The susceptibility of females of An. stephensi to
three concentrations of lambdacyhalothrin, deltamethrin and
cyfluthrin insecticides culminated in full scale mortality at the
highest diagnostic dose. The maximal residual time of these three
insecticides on plaster and cement walls was estimated to be about
three months. There was no significant difference in the mortalities
of An. stephensi on different sprayed surfaces (P=0.653).
Conclusion: All field-collected An. stephensi populations exhibit
gross susceptibility to all diagnostic doses of the three evaluated
insecticides. In endemic areas, lambdacyhalothrin reveals a
slightly longer residual activity than the other two insecticides.
