Lyme disease is a bacterial infection that's spread primarily though the bite of an infected black-legged tick. These tiny insects, which can carry the bacteria Borrelia burgdorferi, typically live in wooded and grassy areas.
While lyme disease was once thought of as fairly rare, recent estimates from the Centers for Disease Control and Prevention suggest it's actually 10 times more common than we'd assumed, infecting roughly 300,000 Americans each year.
Common symptoms of lyme disease (in blue) include fever, headache, fatigue, and a characteristic bulls-eye skin rash. But if left untreated, the infection can spread to the joints, heart, and nervous system and cause more serious problems. Luckily, most cases can be treated successfully with antibiotics.
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