Infectious Diseases - Lyme Disease

Spread by the bites of infected deer ticks, Lyme disease is the most commonly reported vector-borne disease in the United States. Lyme disease is caused by the Borrelia burgdorferi organism and produces early symptoms such as skin rashes, headache, fever, and general illness; if untreated, the disease can cause arthritis and heart damage.

The CDC began to track Lyme disease in 1982, and the disease was added to the list of nationally notifiable diseases in 1990. Figure 7.3 shows the dramatic increase in the number of reported cases from 1982 to 2000. In 2000 the CDC received reports of 17,730 cases of Lyme disease from forty-four states and the District of Columbia, with the majority of cases occurring in the northeastern and north central states. In 2002, 23,763 cases of Lyme disease were reported to the CDC. Twelve states—Connecticut, Rhode Island, New Jersey, New York, Pennsylvania, Delaware, Massachusetts, Wisconsin, Minnesota, Maine, New Hampshire, and Maryland—accounted for 95 percent of the total cases reported in 2002.

In December 1998 the FDA announced approval for the world's first vaccine against Lyme disease. Doctors warned, however, that although the vaccine, LYMErix, developed by SmithKline Beecham, would help prevent Lyme disease, it would not eliminate the threat entirely. To achieve the best immunity, a person must receive a series of three shots over the course of a full year.

FIGURE 7.3
Number of cases of Lyme disease, by year, 1982–2000

Because LYMErix is not 100 percent protective, the FDA warned that people still must take precautions against ticks. Wearing long-sleeved shirts and long pants, tucking pants legs into socks, and spraying the skin and/or clothing with tick repellents can keep ticks away from the skin. If a tick is found on the body, it should be removed promptly, and the affected individual should be alert for early symptoms of the disease. Immediate medical treatment is imperative to prevent long-term health damage from Lyme disease.