Elevation as a Driver of Lyme Disease Dynamics: Density, Phenology, and Borrelia burgdorferi Infection Rate of Ixodes scapularis Ticks in Central Vermont, Poster 27

Lyme disease incidence is on the rise in northern New England. This prompts the need to understand the disease – caused by the bacterium Borrelia burgorferi - and its ecological determinants – partially transmitted... [ view full abstract ]

Lyme disease incidence is on the rise in northern New England. This prompts the need to understand the disease – caused by the bacterium Borrelia burgorferi - and its ecological determinants – partially transmitted through the tick Ixodes scapularis’s life cycle. The changes in biotic and abiotic factors that occur with increasing elevation are similar to changes due to geographical climatic variation. Therefore, patterns observed along an elevational gradient may provide insights into the influence of climate on disease dynamics. Recent studies have shown that B. burgdorferi infection rates and genotype distribution are influenced by climate and vector seasonality in the United States, and a number of studies in Europe have established a negative correlation between elevation and B. burgdorferi infection. In this study, we investigate elevation’s effect on (a) the density and infection of I. scapularis and (b) phenology of I. scapularis. Our preliminary results indicate a negative correlation between elevation and adult and nymph tick densities. A threshold relationship fit better than a linear model, with a cutoff at ~300m. Ultimately, this study will improve understanding of Lyme disease in the Northeast and inform future investigation and prevention efforts.