Erythema migrans

"Erythema migrans is the only manifestation of Lyme disease in the United States that is sufficiently distinctive to allow clinical diagnosis in the absence of laboratory confirmation.

The initial sign of about 80% of Lyme infections is an erythema migrans (EM) rash at the site of a tick bite, often near skin folds, such as the armpit, groin, or back of knee, on the trunk, under clothing straps, or in children's hair, ear, or neck.

[10][12][13]The EM rash is often accompanied by symptoms of a viral-like illness, including fatigue, headache, body aches, fever, and chills, but usually not nausea or upper-respiratory problems.

Within days or weeks, additional EM rashes, usually smaller, can appear at other sites, or the infection can cause more serious complications in the nervous system, heart, or joints.

Afzelius published his work 12 years later and speculated the rash came from the bite of an Ixodes tick, meningitic symptoms and signs in a number of cases and that both sexes were affected.

[18] In the 1920s, French physicians Garin and Bujadoux described a patient with meningoencephalitis, painful sensory radiculitis, and erythema migrans following a tick bite, and they postulated the symptoms were due to a spirochetal infection.

In the 1940s, German neurologist Alfred Bannwarth described several cases of chronic lymphocytic meningitis and polyradiculoneuritis, some of which were accompanied by erythematous skin lesions.