U.S. Lyme disease incidence rates in 2022, by state

In 2022, the U.S. states with the highest rates of Lyme disease were Rhode Island, Vermont, and Maine. However, the states with the highest total number of Lyme disease cases were New York, Pennsylvania, and New Jersey. That year, there were a total of 2,653 cases of Lyme disease in the state of Maine, with an incidence rate of 192.6 per 100,000 population.

What is Lyme disease?

Lyme disease is caused by bacteria usually transmitted to humans through the bite of a tick. Lyme disease is the most common vector-borne disease in the United States, however it is much more prevalent in some states than others, with the upper Midwest and the Northeastern states most at risk. Symptoms of Lyme disease can vary and usually come in stages but may include a rash, fever, headache, stiffness in the joints, tiredness, and muscle aches and pains. Lyme disease is usually treated with antibiotics. In 2022, funding for Lyme disease from the National Institutes of Health (NIH) totaled around 50 million U.S. dollars.

Trends in Lyme disease

Although the number of Lyme disease cases per year fluctuates, over the past couple decades, the number of Lyme disease cases in the United States has steadily increased. Between 1996 and 2022, the highest number of Lyme disease cases was in the year 2022 when over 62,500 cases were reported. The lowest number reported during this period was in 1997, with around 12,800 cases. Cases of Lyme disease are much more common in the summer months of June and July as this is when people are most likely to encounter ticks. The risk of Lyme disease is expected to increase in the future as climate change contributes to an expanded habitat for ticks.