FIELD-EVALUATION OF 4 REPELLENTS AGAINST LEPTOCONOPS-AMERICANUS (DIPTERA, CERATOPOGONIDAE) BITING MIDGES

Four repellents, deet, AI3-37220, AI3-35765, and CIC-4, prepared as 12 .5% ethanol solutions, were evaluated against biting midges on Stansbu ry Islands, UT. Leptoconops americanus Carter was the only species tha t was biting human volunteers during the study. This species bit prima rily on the ears at rates up to 840 bites per hour. All four repellent s significantly reduced the number of bites on treated volunteers. AI3 -37220 consistently provided the longest period of protection, giving 97 and 74% protection at 4 and 8 h, respectively. In a direct statisti cal comparison, AI3-37220 significantly outperformed deet. CIC-4 and A I3-35765 were the least effective repellents, providing 45-78 protecti on 8 h after application.