Susceptibility of cockroaches Blattella germanica L. collected from hospitals to selected pyrethroid and carbamate insecticides

The resistance to four pyrethroid insecticides: permethrin, deltamethrin, cypermethrin, etofenprox, and to two carbamate insecticides--bendiocarb, propoxur was investigated on field strains of German cockroaches (Blatella germanica L.) caught in hospitals from various parts of Poland. The tests were carried out only on males by the contact method recommended by the WHO. The resistance was evaluated on the basis of LT50S and resistance ratios (RRs). The tested fields strains showed high or moderate resistance to permethrin, deltamethrin, cypermethrin and bendiocarb: moderate resistance or tolerance to etofenproks (this compound has been never used in Poland before), and tolerance or susceptibility to propoxur.