A new method of deploying entomopathogenic fungi to control adult Aedes aegypti mosquitoes

A new system for deployment of fungus-impregnated black cloths was tested against Aedes aegypti. A PET trap was placed in a test chamber to evaluate attractiveness to female A.aegypti with black cloths covered in adhesive film or adhesive film only for 24 and 48hr. Traps with fungus (Metarhizium anisopliae and Beauveria bassiana)-impregnated black cloths were tested against female mosquitoes for different time periods (3h to 48hr) in the chambers. Traps were then tested under intradomicile conditions against sucrose and blood-fed insects. Experiments were carried out to ascertain the minimum number of PET traps need to be deployed per test room and to test the effect of different periods of exposure to traps. Exposing the insects for 24 and 48hr to a PET trap with adhesive film + black cloth resulted in higher rates of trapped mosquitoes (38.6% and 68%, respectively) when compared with adhesive film only (6% and 12.6%, respectively). Both fungal species were effective at reducing survival rates when mosquitoes were exposed to traps for 24hr or 48hr. Lower exposure times did not significantly alter survival rates when compared to controls. The results showed that five traps or three traps per room were equally effective in reducing mosquito survival rates when testing both fungal species. The results for sucrose-fed insects showed significant reductions in survival when exposed to M.ansiopliae or B.bassiana for 24, 48 or 120hr when compared to control survival, with the lowest survival rates seen following 48- or 120-hr exposures. Survival of blood-fed mosquitoes exposed to fungus-impregnated traps for 48hr was not significantly different to the controls; however, longer exposure times significantly reduced survival rates. PET traps could be an effective system for deploying fungus-impregnated cloths in residences, facilitating cooperation of volunteers and reducing distribution time.