Two significant factors contribute to the lower Lyme disease infection rates in the southeastern US. First, black-legged ticks in the north attach to and feed off mammals that are efficient at carrying and spreading the bacteria that causes the disease. Ticks in the south mostly attach to lizards that aren’t as efficient of disease carriers.
We also found that low tick densities at some southern sites, such as Tennessee and North Carolina, contributed to the low infection rates and low numbers of host-seeking ticks. This science can help researchers understand and predict the spread of Lyme disease bacteria and other vector-borne diseases. This new knowledge can help determine where human health threats could occur and inform management decisions to protect communities.