Symptoms of poisoning for deltamethrin and cis-permethrin on nymphs III of
Triatoma infestans were described. The time required for incoordination and
paralysis were determined. Deltamethrin was equal or more rapid in the
onset of the first effect (accordingly to dose), and cis-permethrin in the
onset of the second one. There were no significant differences between
incoordination doses 50% (IncD50s) at different times for the two
pyrethroids. They showed equivalent incoordination power, but the nymphs
treated with deltamethrin recovered slightly more rapid and in greater
amount than the nymphs treated with cis-permethrin. The recovery was
inhibited by the simultaneus application of piperonyl butoxide. This result
suggests that biotransformation by mixed-function microsomal oxidases are
involved in the process of recovery.