Some cases are seronegative.
There are cross reactions with antibodies to EB virus, Rickettsia, syphilis, and Leptospira. These diseases should be ruled out clinically or by specific tests when evaluating patients with Lyme disease antibody present. It is widespread in the U.S. and is caused by Borrelia burgdorferi, a spirochete transmitted by the bite of the tick Ixodes dammini. The disease has protean manifestation, can become chronic, and responds to antibiotics, so prompt proper diagnosis is important. All patients with chronic disease will have positive assays.