Activity and biological effects of neem products against arthropods of medical and veterinary importance

Botanical insecticides are relatively safe and degradable, and are readily available sources of biopesticides. The most prominent phytochemical pestic ides in recent years are those derived from neem trees, which have been stu died extensively in the fields of entomology and phytochemistry, and have u ses for medicinal and cosmetic purposes. The neem products have been obtain ed from several species of neem trees in the family Meliaceae. Six species in this family have been the subject of botanical pesticide research. They are Azadirachta indica A. Juss, Azadirachta excelsa Jack, Azadirachta siame ns Valeton, Melia azedarach L., Melia toosendan Sieb. and Zucc., and Melia volkensii Gurke. The Meliaceae, especially A. indica (Indian neem tree), co ntains at least 35 biologically active principles. Azadirachtin is the pred ominant insecticidal active ingredient in the seed, leaves, and other parts of the neem tree. Azadirachtin and other compounds in neem products exhibi t various modes of action against insects such as antifeedancy, growth regu lation, fecundity suppression and sterilization, oviposition repellency or attractancy, changes in biological fitness, and blocking development of vec tor-borne pathogens. Some of these bioactivity parameters of neem products have been investigated at least in some species of insects of medical and v eterinary importance, such as mosquitoes, flies, triatomines, cockroaches, fleas, lice, and others. Here we review, synthesize, and analyze published information on the activity, modes of action, and other biological effects of neem products against arthropods of medical and veterinary importance. T he amount of information on the activity, use, and application of neem prod ucts for the control of disease vectors and human and animal pests is limit ed. Additional research is needed to determine the potential usefulness of neem products in Vector control programs.