Synthetic pyrethroid aerosol (0.02% deltamethrin +0.13% allethrin) was found less effective in control
of cockroaches in the present study in catering establishments in comparison to houses as well as it was less effective in comparison to propoxur.
Resistance to deltamethrin in B. germanica has been reported in some studies.
The use of synthetic pyrethroids of the 2nd type (viz. deltamethrin) against cockroaches has been recommended by workers because they can produce a higher insecticidal effect as well as irreversible knock-down