when compared to a susceptible strain. Five
strains, resistant to both cypermethrin and permethrin, were also resistant to DDT,
phenothrin and deltamethrin. Propoxur resistance in ten strains was suppressed with
the synergists,piperonyl butoxide (PBO) and S,S,S-tributylphosphorotrithioate
(DEF!), suggesting monooxygenase and esterase involvement in the resistance.
However, the levels of resistance for cypermethrin and permethrin were not
affected when using either PBO or DEF