LYME DISEASE

Lyme disease has been known in this country as a medically important illness since 1975 and has become the most notorious tick-transmitted illness in North America. In the last decade it increased tenfold and it is estimated that more than 9,677 cases occurred in the US in 1992. It is caused by the spirochete, Borrelia burgdorferi, and is transmitted in the Northeast primarily by the blacklegged tick, Ixodes scapularis (= I. dammini), a tick which is abundant in many parts of Rhode Island, especially southern and coastal areas.

The larval and nymphal stages of the blacklegged tick feed primarily on mammals and birds. One mammal in particular, the white-footed mouse, serves admirably as the host for these two stages. In addition, this mouse harbors the spirochete and is a major reservoir host for the disease. In this way, the spirochete is acquired by the tick while feeding on the mouse. If by chance the nymphal or adult ticks harboring the spirochetes were to feed on humans, the spirochete could be transmitted during the blood meal.

GENERAL INFORMATION

EPIZOOTIOLOGY

SYMPTOMS, DIAGNOSIS, AND TREATMENT