Back to homepage

Vector-Borne Diseases main page

Send us an email to share your concerns.

Lyme Disease
Lyme disease is a serious illness caused by the bacterium Borrelia burgdorferi and transmitted to humans by the bite of infected deer ticks.   In 2005 there were 2336 cases of Lyme disease in Massachusetts.

Most cases of Lyme disease can be treated successfully with a few weeks of antibiotics. Steps to prevent Lyme disease include using insect repellent, removing ticks promptly, landscaping, and integrated pest management. The ticks that transmit Lyme disease can occasionally transmit other tick-borne diseases as well.

The website of the CDC (Centers for Disease Control) is a good source for information about Lyme disease.

The Mass. Dept. of Public Health offers a useful fact sheet on Lyme Disease, and a website on ticks and tick borne diseases.

If you are interested in the science behind the spread of Lyme disease, click here to see the work of UMass entomologist Stephen M. Rich, who is tracking Lyme disease throughout New England.

According to the CDC, Typical symptoms include fever, headache, fatigue, and a bulls-eye skin rash. Lyme disease can infect several parts of the body, producing different symptoms at different times. Not all patients with Lyme disease will have all symptoms. If you believe you may have Lyme disease, it is important that you consult your health care provider for proper diagnosis.

The first sign of infection is usually a circular bull's-eye rash. This rash occurs in approximately 70-80% of infected persons and begins at the site of a tick bite after a delay of 3-30 days. The rash gradually expands over a period of several days, reaching up to 12 inches across. The center of the rash may clear as it enlarges, resulting in a bull’s-eye appearance. It may be warm but is not usually painful. Patients also experience fatigue, chills, fever, headache, and muscle and joint aches, and swollen lymph nodes. In some cases, these may be the only symptoms of infection.

Untreated, the infection may spread to other parts of the body within a few days to weeks, producing a range of separate symptoms. These include loss of muscle tone on one or both sides of the face (called "Bell’s" palsy), severe headaches and neck stiffness due to meningitis, shooting pains that may interfere with sleep, heart palpitations and dizziness due to changes in heartbeat, and pain that moves from joint to joint. These symptoms may go away without treatment.

Approximately 60% of patients with untreated infection will begin to have intermittent bouts of arthritis after several months, with severe joint pain and swelling. In addition, up to 5% of untreated patients may develop chronic neurological complaints months to years after infection. These include shooting pains, numbness or tingling in the hands or feet, and problems with concentration and short term memory.

Most cases of Lyme disease can be cured with antibiotics, especially if treatment is begun early in the course of illness.

A few patients have symptoms that last months to years after treatment with antibiotics. These symptoms can include muscle and joint pains, arthritis, cognitive defects, sleep disturbance, or fatigue. The cause of these symptoms is not known. There is some evidence that they result from an autoimmune response, in which a person’s immune system continues to respond even after the infection has been cleared.




deer tick


The tiny deer tick, shown above is the carrier for Lyme Disease.

It is also known as the black-legged tick, or the bear tick.

The scientific name is Ixodes scapularis.