Do soil microorganisms such as fungi explain variation in local Lyme disease risk in northern Dutchess County?

Lyme disease has emerged as the most common tick-borne disease in the United States and the sixth most common notable disease. A blacklegged tick (Ixodes scapularis) infected with the bacteria, Borrelia burgdorferi, transmits the illness to humans and wildlife. Across northern Dutchess County, there is variation in the number reported Lyme disease cases, with certain areas having higher incidence than others. Thus, it is important to understand the ecological factors that explain this variation of risk in peridomestic environments. Recent research has focused on the role of entomopathogenic fungi as a potential risk indicator. Entomopathogenic fungi are native fungi that can act as parasites in killing ticks and other insects through the production of spores that then penetrate the exoskeleton of the host. The most common entomopathogenic fungi, Beauveria bassiana and Metarhizium anisopliae, have been shown to reduce the fitness of the blacklegged tick. There is less known about the presence of entomopathogenic fungi in relation to Lyme disease incidence. In this study, I investigated the relationship between the presence of natural enemies and the number of Lyme disease cases in northern Dutchess County. I compared the presence of natural enemies in soil samples from private properties using an established waxworm assay to assess the abundance of microorganisms. There was no significant relationship between the presence of natural enemies and the number of Lyme disease cases. There was also no significant relationship between the abundance of blacklegged ticks and the number of Lyme disease cases. These results reveal that there needs to be continuing research to determine which other environmental factors explain the variation of Lyme disease risk. Further research may be conducted during peak season of nymphs to better understand the relationship of how the abundance of blacklegged ticks affects the number of Lyme disease cases