ABSTRACT
Vector resistance to insecticides is becoming a major obstacle to malaria prevention measures. A baseline survey was carried out in Khartoum city, Sudan, during September-November 2007, to map the insecticide susceptibility status ofAnophelesarabiensis and to examine the correlation with insecticide usage in urban agriculture. Susceptibility tests were conducted in 6 sentinel sites representing urban and periurban strata of the city. Mortality rates and knockdown times were calculated for 8 insecticides on a total of 9820 specimens. An. arabiensis was susceptible to bendiocarb (98.1%), propoxur (100%), fenitrothion (100%), deltamethrin (99.8%) and lambda-cyhalothrin (99.2%). Susceptibility rates were significantly different between urban and periurban sites for malathion (80.8% vs 56.0%), DDT (99.0% vs 95.0%) and permethrin (98.5% vs 96.3%). The 50% knockdown times were significantly higher in periurban than urban populations of An. arabiensis for deltamethrin, lambda-cyhalothrin and malathion.
Subject(s)
Anopheles/drug effects , Insect Vectors/drug effects , Insecticides/pharmacology , Malaria/prevention & control , Mosquito Control/methods , Animals , Cities/statistics & numerical data , Drug Resistance , Female , Humans , Malaria/transmission , Male , Polymerase Chain Reaction , Sudan , Urban PopulationABSTRACT
Vector resistance to insecticides is becoming a major obstacle to malaria prevention measures. A baseline survey was carried out in Khartoum city, Sudan, during September-November 2007, to map the insecticide susceptibility status of Anopheles arabiensis and to examine the correlation with insecticide usage in urban agriculture. Susceptibility tests were conducted in 6 sentinel sites representing urban and periurban strata of the city. Mortality rates and knockdown times were calculated for 8 insecticides on a total of 9820 specimens. An. arabiensis was susceptible to bendiocarb [98.1%], propoxur [100%], fenitrothion [100%], deltamethrin [99.8%] and lambda-cyhalothrin [99.2%]. Susceptibility rates were significantly different between urban and periurban sites for malathion [80.8% vs 56.0%], DDT [99.0% vs 95.0%] and permethrin [98.5% vs 96.3%]. The 50% knockdown times were significantly higher in periurban than urban populations of An. arabiensis for deltamethrin, lambda-cyhalothrin and malathion
