title: Chemical and Plant-Based Insect Repellents: Efficacy, Safety, and Toxicity.
abstract: Most emerging infectious diseases today are arthropod-borne and cannot be prevented by vaccinations. Because insect repellents offer important topical barriers of personal protection from arthropod-borne infectious diseases, the main objectives of this article were to describe the growing threats to public health from emerging arthropod-borne infectious diseases, to define the differences between insect repellents and insecticides, and to compare the efficacies and toxicities of chemical and plant-derived insect repellents. Internet search engines were queried with key words to identify scientific articles on the efficacy, safety, and toxicity of chemical and plant-derived topical insect repellants and insecticides to meet these objectives. Data sources reviewed included case reports; case series; observational, longitudinal, and surveillance studies; and entomological and toxicological studies. Descriptive analysis of the data sources identified the most effective application of insect repellents as a combination of topical chemical repellents, either N-diethyl-3-methylbenzamide (formerly N, N-diethyl-m-toluamide, or DEET) or picaridin, and permethrin-impregnated or other pyrethroid-impregnated clothing over topically treated skin. The insecticide-treated clothing would provide contact-level insecticidal effects and provide better, longer lasting protection against malaria-transmitting mosquitoes and ticks than topical DEET or picaridin alone. In special cases, where environmental exposures to disease-transmitting ticks, biting midges, sandflies, or blackflies are anticipated, topical insect repellents containing IR3535, picaridin, or oil of lemon eucalyptus (p-menthane-3, 8-diol or PMD) would offer better topical protection than topical DEET alone.
authors.affiliation: Schools of Public Health and Medicine, Louisiana State University, Health Sciences Center, New Orleans, LA. Electronic address: jdiaz@lsuhsc.edu.
authors.forename: James H
authors.initials: JH
authors.lastname: Diaz
mesh_terms: D000053:Acari / Q000187:drug effects*; D056810:Acaricides / Q000009:adverse effects / Q000494:pharmacology* / Q000633:toxicity; D000818:Animals; D001179:Arthropod Vectors / Q000187:drug effects*; D003141:Communicable Diseases / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D007299:Insect Bites and Stings / Q000209:etiology / Q000517:prevention & control*; D007302:Insect Repellents / Q000009:adverse effects / Q000145:classification / Q000494:pharmacology* / Q000633:toxicity; D007313:Insecta / Q000187:drug effects*; D007306:Insecticides / Q000009:adverse effects / Q000145:classification / Q000494:pharmacology* / Q000633:toxicity; D010936:Plant Extracts / Q000009:adverse effects / Q000737:chemistry / Q000494:pharmacology / Q000633:toxicity
chemical_list: D056810:Acaricides; D007302:Insect Repellents; D007306:Insecticides; D010936:Plant Extracts
keywords: arthropod-borne; infectious diseases; insect; insecticides; mosquito-borne; repellents; tick-borne