Laboratory and field evaluation of the repellents deet, CIC-4, and AI3-37220 against Anopheles farauti (Diptera: Culicidae) in Australia

Laboratory and field tests of the repellents diethyl methylbenzanide (deet), 1-(3-cyclohexen-1-yl-carbonyl)-2-methylpiperidine (AI3-37220), and (2-hydroxymethylcyclohexyl) acetic acid lactone (CIC-4) were conducted against Anopheles farauti s.s. Laveran, an important malaria vector in the southwest Pacific region. In the laboratory, An. farauti was tolerant of all 3 repellents, but deet and CIC-4 provided significantly better protection than AI3-37220. The field study was conducted in rain Forest located near Innisfail, northern Queensland, and tested 25% (vol:vol) ethanol solutions of each repellent against An. farauti. All 3 repellents provided >95% protection against An. farauti for 5 h after application. In contrast to the laboratory tests, protection provided by AI3-37220 was significantly better than that by either deet or CIC-4, and there was no difference between protection by deer and CIC-4. The protection by deet and CIC-4 declined 8 h after application and provided less than or equal to 50% protection at 9 h. In contrast, A13-37220 provided greater than or equal to 94% protection for 9 h.