Submitted to: Journal of Medical Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 16, 1999
Publication Date: N/A
Interpretive Summary: This paper reports the results of a preliminary survey of fungal pathogens of deer ticks, the vector of the bacterium that causes Lyme disease, one of the most serious animal-borne diseases of humans to emerge in the NE quadrant if the US in recent years. This survey found a very low incidence of natural infection in adult female deer ticks by fungal pathogens are known to have wide host affinities for diverse insect hosts. While the low incidence of the natural infections is discouraging, it is important that the fungus found to affect the target populations is one that can be manipulated easily in culture and is already being used for practical biological control of aphids, whiteflies, and other insect pests in greenhouses in several parts of the world. This study provides some real hope that continuing research may lead to the practical utilization of fungi for the biological control of tick populations that transmit Lyme disease or other diseases to humans. The collections of ticks and fungal bioassays were done by University of Rhode Island scientists; the fungi were identified at and are preserved by the ARS Collection of Entomopathogenic Fungal Cultures (Ithaca, NY).
Free-living larvae, nymphal, and adult Isodes scapularis Say were collected from scattered locales in southern New England and New York to determine infection rates with entomopathogenic fungi. Infection rates of larvae, nymphs, males, and females were 0% (571), 0% (272), 0% (57), and 4.3% (47), respectively. Two entomopathogenic fungi were isolated from field-collected dI. SCAPULARIS females from Fire Island, NY. Isolates were identified as VERTICILLIUM LECANII (Zimmermann) Viegas and VERTICILLIUM sp. (a member of The VERTICILLIUM LECANII species complex).