Lyme Disease as a Public Health Concern

Lyme disease is the most common vector-borne disease in the United States, affecting tens of thousands of people each year and costing millions of dollars. There are many symptoms associated with Lyme disease, including fever, chills, headache, fatigue, muscle and joint aches, and swollen lymph nodes. Given the potential physical and financial impacts of Lyme disease, the study authors sought to understand how climate change might affect the incidence of Lyme disease in the eastern and upper Midwestern U.S., as well as the estimated healthcare expenses.

Climate Change and Lyme Disease

As temperatures and changes in precipitation have shifted, so too has the number and range of ticks, which are the primary vector for Lyme disease. At the same time, human outdoor recreation patterns are likely to change, potentially bringing more people into contact with ticks. The authors found that, despite an expected decrease in cases in Virginia and North Carolina, an overall increase in incidence in New England and the upper Midwestern U.S. was expected.

Increase of Incidence—by Temperature Rise—and Costs

An increase of Lyme disease would lead to an increase in related health costs.

The authors found:

• Assuming 3°C of warming baseline, approximately a 38 percent increase of Lyme diseases cases and associated healthcare costs in this region from present-day estimates 
• At 6°C of warming, the most extreme scenario in the paper, the authors projected a 146 percent increase in cases and costs above current levels. 

These results may inform decision-makers tasked with addressing climate risks, the public, and healthcare professionals preparing for treatment and prevention of Lyme disease.