Susceptibility status of female anopheles’ mosquito to organophosphate and carbamate insecticides in market environs in Itu LGA, Akwa Ibom State, Nigeria

Malaria remains a serious public health problem and is still responsible for death of individuals globally with the female Anopheles gambiae established to be one of the major vectors which aid the transmission of this disease. This study examined the susceptibility and resistance of An. gambiae to carbamate and organophosphate which has not been frequently used in vector control in Nigeria. The CDC (Centres for Disease Control and Prevention) bottle bioassay was employed to measure the susceptibility of An. gambiae to insecticides. The procedure involved 2–5-day old An. gambiae adult mosquito populations starved from blood. In this study, we employed a diagnostic time of 30 minutes to administer doses of 12.5µg/bottle of Bendiocarb and Propoxur (Carbamates) and 20µg Pirimiphos-methyl (Organophosphate) to Anopheles spp. populations. The knockdown effect of the three insecticides indicated that bendiocarb and propoxur (carbamates) had a mortality of 98% while pirimiphos-methyl (organophosphate) had 81% at 30 minutes, regarded as the HUH for measuring resistance/susceptibility of insecticides. Further exposure at 60 minutes yielded 100% mortality for both bendiocarb and propoxur while 98% mortality was applicable in pirimiphos-methyl insecticides. An. gambiae was susceptible to bendiocarb and propoxur insecticides and resistant to pirimiphos-methyl. Invariably, vector control decision-making in the area will be influenced by the result of the study being that it is a baseline data/information. It is paramount that before any vector control strategies are implemented, sufficient susceptibility/resistance data be taken into thought