Dear Doctor: We moved from the city to rural Massachusetts, and suddenly Lyme disease is a real threat. I’ve read about it forever, but now that we’re here, I realize I don’t know much about the disease. How do you know if you’ve got it? And how do we protect ourselves and our kids?
Dear Reader: Lyme disease is one of a range of illnesses that can occur when an individual is bitten by a tick. In the case of Lyme disease, the tick has been infected by a bacterium known as Borrelia burgdorferi. In the eastern half of the United States, the bacterium is carried by the blacklegged tick, also known as the deer tick. On the Pacific coast, the disease is spread by the western blacklegged tick.
In order to transmit the disease, the tick must have been attached to its host for at least 24 hours. But because these ticks are quite small -- they range in size from a poppy seed to a sesame seed, depending on the stage of their life cycle -- they can be easy to miss. About 30,000 cases of Lyme disease get reported to the Centers for Disease Control and Prevention each year, but epidemiologists estimate that the true number is closer to 300,000.
One of the challenges of Lyme disease is that the symptoms, which vary depending on the stage of infection, are similar to indicators of other common conditions. In its early stages, Lyme disease can cause fever, swollen lymph nodes, chills and body aches, which are also symptoms of upper respiratory viral infections. Another early symptom can be a localized skin rash, which sometimes clears at the center as the edges expand, forming a distinctive target shape. However, this rash has been found to be a symptom in only about 70% of Lyme cases. To add to the uncertainty, the rash doesn’t always follow the target-shaped pattern. Stiffness and joint swelling, which can arise days or months after the tick bite, mimic arthritis.
Additional symptoms that can arise days or months after an infection include pain in the joints and tendons, heart arrhythmias, dizziness, nerve pain, shortness of breath, loss of muscle tone on one side of the face and even changes to memory and cognition. Anyone with these symptoms who has been bitten by a tick, or who lives in tick country, should seek medical attention. Diagnosis includes a history of potential tick exposure, and it may include lab tests to detect antibodies to the bacterium. Treatment of early-stage Lyme disease with antibiotics such as doxycycline, amoxicillin or cefuroxime is usually quite effective.
Ticks are found in wooded and brushy areas, lawns and gardens, and on outdoor pets. Protect yourself with light-colored clothing, which makes ticks easier to see. Clothes and gear can be treated with the insecticide permethrin. Tuck pants into socks and remember protection for your head. Always perform whole-body tick checks after outdoor activities. If bitten, remove the tick with fine-tipped tweezers, grasping as close to skin as possible. Clean area thoroughly, and see if your physician wants you to save the tick. If so, wrap it in tape. And remember -- a tick bite doesn’t automatically equal Lyme disease.
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