Submitted to: Journal of Medical Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/27/2002
Publication Date: 11/11/2002
Citation: BARNARD, D.R., BERNIER, U.R., POSEY, K.H., XUE, R. REPELLENCY OF IR3535 TM, KBR3023, PARA-MENTHANE-3,8-DIOL, AND DEET TO BLACKSALT MARSH MOSQUITOES (DIPTERA: CULICIDAE) IN THE EVERGLADES NATIONAL PARK USA. JOURNAL OF MEDICAL ENTOMOLOGY. 2002. 39(6). p.895-899. Interpretive Summary: A recent U.S. Environmental Protection Agency ruling exempting certain repellents from regulation under the Federal Insecticide, Fungicide, and Rodenticide Act stimulated the development of topical insect repellents that do not contain deet. Scientists at the Center for Medical, Agricultural, and Veterinary Entomology in Gainesville, FL tested three of these repellents (KBR3023, IR3535, and para-menthane-diol [PMD]) against human-biting populations of the salt marsh mosquito in the Everglades National Park, FL. The results of the tests showed that all three non-deet repellents provided 3-4 hours of protection from mosquito bites, that each was an effective alternative repellent for deet, and that none of the repellents manifested objectionable odor or consistency, or was irritating to the skin.
Technical Abstract: IR3535 TM, KBR3023, para-menthane-3,8-diol (PMD), and deet were evaluated in controlled studies with human subjects for repellency to black salt marsh mosquitoes (Ochlerotatus taeniorhynchus (Wiedemann)) in the Everglades National Park, Florida, USA. In tests of 6 h duration, with an average mosquito biting pressure on exposed forearm skin of 19.5 (plus or minus 13.7) bites per minute, the mean percent repellency (SE) for IR3535 TM, KBR3023, PMD, and deet was 88.6 (3.2), 97.5 (1.7), 89.2 (2.9), and 94.8 (2.5), respectively. Mean complete protection times (SE) for IR3535, KBR3023, PMD, and deet were 3.0 (1.0), 5.4 (0.6), 3.8 (1.4), and 5.6 (0.5) h, respectively. Ethanol controls provided 0 percent repellency. When mosquito biting rates on the untreated forearm of subjects receiving deet or a deet alternative on the opposite forearm were compared with biting rates on untreated subjects (ethanol only on one forearm), biting rates on the former were reduced early in tests by 23 to 40 percent, but increased late in tests to exceed untreated subjects by as much as 22 percent.