Newly released data is the latest to show that Lyme disease cases in the U.S. are on the rise. The research found that private insurance claims related to the tickborne disease have substantially climbed since 2007, including more recently in the last five years. This relative increase was especially dramatic in rural areas.
The research comes from FAIR Health, an independent nonprofit organization that formed in 2009 as part of a settlement between New York State and local health insurers over allegedly fraudulent out-of-network charges. Since then, in collaboration with health policy researchers, the organization has collected and regularly analyzes reams of private insurance claims data, in what they say is the largest database of its kind in the U.S.
For this new report, researchers tracked claims that mentioned a diagnosis of Lyme disease dating back to 2007. Between 2007 and 2021, they found that claims reported from people living in cities and other urban areas rose by 65%, and by 357% from people in rural areas. The report is also an update to an analysis conducted by FAIR Health in 2017, and Lyme disease diagnoses have continued increasing since then as well. Between 2016 and 2021, claims from urban areas rose by 19% and by 60% in rural areas. An accompanying infographic can be seen here.
“Overall diagnoses are more frequent in urban areas because the population is larger in urban areas. However, our data indicate that diagnoses of Lyme disease in rural areas are increasing more rapidly,” Thomas Swift, chief operating officer at FAIR Health, told Gizmodo in an email.
The newest findings line up with other research indicating that Lyme and other tickborne diseases are becoming more common over time. Based on their own analysis of commercial insurance data, for instance, researchers with the Centers for Disease Control and Prevention recently estimated that over 450,000 Americans are now being diagnosed and treated for Lyme annually—more than 10 times the number of reported cases and up from the 300,000 annual cases previously estimated by the CDC.
FAIR Health’s data also suggests that people outside of areas where Lyme is known to be endemic are coming across these disease-carrying ticks more often, at least in some years. In 2017, for example, claims from North Carolina rose substantially, with the state having the third highest proportion of Lyme-related claims against all diagnoses that year. By 2021, North Carolina was no longer in the top five, but Maine had supplanted it as third on the list—the latter state having previously never been in the top five. In both 2017 and 2021, New Jersey, Connecticut, Rhode Island, and Vermont were the four other states with the highest proportion of Lyme-related diagnoses.
Lyme disease is caused by certain Borrelia bacteria (usually B. burgdorferi), and most cases can be readily treated with antibiotics, especially when caught early. But a small percentage of people report lingering symptoms post-infection, which is known as post-treatment Lyme disease syndrome. There is no strong evidence that these symptoms are caused by an ongoing infection from the bacteria—a theory promoted by adherents of “chronic Lyme”—but it may be linked to immune dysfunction following infection. People whose infection isn’t diagnosed and cured early can also develop more serious complications that can persist even after treatment, such as nerve pain and muscle weakness.
Interestingly enough, FAIR Health’s other findings offer support for the increased risk of longer-term illness among Lyme sufferers. Using their data, they compared the outcomes of Lyme patients to the overall population and found that they had a greater chance of being later diagnosed with fatigue, malaise, and other health problems, a pattern seen across all age groups.
There are ongoing efforts to develop an effective vaccine for Lyme. But with climate change continuing largely unimpeded, experts expect that Lyme and other tick-related illnesses will represent an ever-growing thorn in our side—one that doctors and researchers will have to keep a watchful eye on.
“The current pandemic has focused clinical attention on covid-19, but other diseases remain public health issues worthy of notice. FAIR Health’s data indicate that Lyme disease has not gone away but continues to grow,” said Swift.