First made reportable in New Jersey in 1981, Lyme disease is a multi-systemic, inflammatory disorder caused by the spirochete Borrelia burgdorferi that is transmitted primarily through the bite of an infected blacklegged tick, known more familiarly as the deer tick. About 50% of adult and 25% of nymphal blacklegged ticks are infected with Lyme disease spirochetes. The white-footed mouse, Peromyscus leucopus, and Eastern chipmunk, Tamias striatus, are the primary reservoir hosts. The infection is maintained throughout the lifecycles of the tick, but transovarial passage is infrequent.
Within 3 to 30 days following tick bite, Lyme disease is often, but not always, characterized by a distinctive skin lesion known as erythema migrans (EM), which first appears as a red, raised area that expands in size over time and may develop central clearing. Single or multiple lesions are usually preceded or accompanied by a variety of other symptoms, including headache, fever, fatigue, malaise, joint pain, stiff neck, and nausea. If untreated, neurological and cardiac symptoms may develop within weeks or months of the appearance of EM. Finally, individuals may develop swelling and pain in the large joints. In both the early and advanced phases of Lyme disease, symptoms are often recurrent and may become chronic in untreated individuals. During the last 5 years, an average of 2,750 confirmed Lyme disease cases have been reported annually in New Jersey.