In Connecticut, for example, only one percent of the tick population is infected. The first sign of infection is usually a bull's eye rash, a small round ring with a central clearing. The rash extends several inches in diameter, then disappears in a few weeks. The spirochete bacteria, if untreated, can enter the nervous system, causing encephalitis, meningitis, or temporary paralysis of the face. Slowing of the heart occurs in some patients, causing dizziness, faintness, and shortness of breath.
Blood testing is neither completely reliable nor useful early in the infection process.
Blood tests can take months to register a positive result, and positive test results are not guaranteed with an infected patient. Recollection of possible tick exposure, recognition of the characteristic rash and a progression of the typical symptoms can make diagnoses. Lyme Disease is easily prevented through avoidance. The risk of acquiring parasitic ticks can be minimized by wearing long clothing, tucking one's pants into their socks, wearing white clothing which readily display ticks, using insect repellants, and checking one's body thoroughly after any risk of contact. The immediate removal of a tick greatly minimizes transmission potential.