Assessing the Susceptibility Status of Cypermethrin resistance in German Cockroaches (Blattella germanica: Blattellidae) to Hydramethylnon Gel Bait

The German cockroach (Blatella germanica) is one of the most important vectors of public health interest due to its involvement in the transmission of infectious diseases. Different insecticides are used to control cockroaches; however, resistance developed against most of insecticides has made them ineffective. Attempts should always be made to find proper alternatives to control this insect. In the present study, B. germanica was collected from a hospital in Tehran. Insecticide susceptibility of the cockroaches to cypermethrin was determined using the WHO glass jar method and discriminating doses.Mortality was assessed at 14 h intervals after exposure to bait. The results showed a resistance ratio of about 3.4 to cypermethrin and a complete susceptibility of the field strain to Hydramethylnon gel bait insecticide when they were compared with the susceptible strain. Therefore, there was no cross resistance pattern between these insecticides. This report is the first study on the susceptibility status of resistantB. germanica to Hydramethylnon bait in Iran. We suggest that the use of Hydramethylnon gel bait could be used as an effective control method especially when other insecticides fail to control the cockroach populations0.0.