243 Scientific Publications Relating to Insect Vectors from 1995 to 2004 Field Evaluation of Mosquito Coils Derived from Plants against Night-Biting Mosquitoes in Thailand Apiwat Tawatsin, Usavadee Thavara and Jakkrawarn Chompoosri National Institute of Health, Department of Medical Sciences, Ministry of Public Health. Published in Proceedings International Conference on Biopesticides 3, April 21-26, 2002, Kuala Lumpur, Malaysia, 214-220. Abstract Nine plants namely greater galangale (Alpinia galanga), fingerroot (Boesenbergia pandurata), turmeric (Curcuma longa), cardamom (Elettaria cardamomum), neem (Azadirachta indica), Siamese cassia (Cassia siamea), citronella grass (Cymbopogon nardus), eucalyptus (Eucalyptus citriodora) and Siam weed (Eupatorium odoratum) were studies for their efficacy in reducing human-mosquito contact when used in mosquito coils. Each plant material was prepared as 25% in each mosquito coil formulation. Repellency of the 9 mosquito coil formulations and the blank coil against night biting mosquitoes were determined under field conditions in an urban area of Nonthaburi Province, Thailand. Evaluations were carried out by capturing landing-biting mosquitoes on human volunteers and were conducted from 1830 h to 2130 h. Results showed that mosquito coils provided protection against mosquitoes with a ranging from 50% to 71% reduction in biting activity while the blank coil consisting of inert materials only reduced mosquito attacks by about 43%. Mosquito coil containing leaves of citronella grass showed highest efficacy whereas that containing rhizomes of turmeric was least effective. Mosquitoes caught in this study included 12 species belonging to 5 genera (Aedes, Anopheles, Armigeres, Culex and Mansonia), but Cx. vishnui, Culex gelidus and Cx. quinquefasciatus were most predominant species. Keywords Mosquito coil, field evaluations, mosquitoes, Thailand, phytochemicals, biopesticides, personal protection