Lyme disease, caused by the bacterium Borrelia burgdorferi, is transmitted to people through the bite of infected black-legged ticks, often commonly referred to as deer ticks. In the U.S., it is most commonly acquired in New England, mid-Atlantic and upper Midwest states.
Common symptoms include fever, headaches, fatigue and a characteristic round or oval skin rash. If left untreated, the infection can spread beyond the tick bite site, including to skin rashes in other areas of the body. The infection can also spread to the joints, the heart and the nervous system. Some people feel well without symptoms beyond the characteristic rash, called erythema migrans, which can be the classic “bull’s-eye” with central clearing or the more common pink-red oval skin rash.
In most cases, antibiotics are highly effective in the early stages of Lyme disease. The infection is usually resolved with a two- to four-week course of antibiotics, with the duration depending on the presenting problem. This is not the case for people with ongoing symptoms such as fatigue, brain fog or musculoskeletal pains after an initial course of antibiotics. While the mechanisms driving these patients’ problems are unclear, the problems do not appear to respond to additional antibiotics. While some may experience short-term relief from antibiotics, carefully performed clinical trials do not find improvement rates better than placebo. Therefore, additional antibiotics do not have a role — outside of clinical studies — for people with post-treatment Lyme disease syndrome or problems labeled as chronic Lyme disease.
Using repellents such as DEET or permethrin, inspecting for ticks with prompt removal and bathing after exposure to potential tick habitats (grassy, brushy or wooded areas) are steps that can help prevent Lyme disease.
IDSA engages in advocacy efforts that support better Lyme disease diagnosis, treatment, prevention and public education. IDSA has worked with the American Academy of Neurology and the American College of Rheumatology to develop evidence-based clinical practice guidelines for preventing, diagnosing and treating Lyme disease.