The National Institutes of Health wants to find out what causes lingering Lyme disease symptoms like pain, fatigue and brain fog. The NIH’s National Institute of Allergy and Infectious Diseases is funding research into post-treatment Lyme disease syndrome. The agency awarded $3.2 million last month in first-year funding for five projects investigating the causes of chronic Lyme disease. “As tickborne diseases, including Lyme disease, become more common and widespread in the United States, it is increasingly urgent that we understand all facets of the disease, including the root causes of PTLDS,” Hugh Auchincloss, NIAID’s acting director, said in a statement. What we know: — Lyme disease is spread to humans by ticks infected with the Borrelia burgdorferi bacterium. — Most people who contract Lyme respond to a short-term course of oral antibiotics, but some continue to report symptoms after their infection clears. — Chronic Lyme disease has no standard treatment. Despite little evidence that long-term antibiotics are effective, some doctors prescribe them, but the drugs carry their own risks and side effects. What we don't know: Chronic Lyme disease’s cause. Some scientists hypothesize that chronic Lyme could be an autoimmune response to the Borrelia burgdorferi bacterium, meaning patients’ immune systems are attacking their own cells. Effective treatments are difficult to develop without understanding the biological mechanism causing chronic Lyme. Why it matters: The Centers for Disease Control and Prevention estimates that 476,000 people in the U.S. become infected with Lyme disease each year. As many as 1 in 5 have lingering symptoms. What’s next? In addition to better treatments, understanding the biological mechanisms that trigger post-treatment Lyme disease syndrome could further understanding of other infection-related chronic diseases, like long Covid and chronic fatigue syndrome.
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