Originally discovered in the mid-70's after a cluster of cases of arthritis was seen in children from Old Lyme, CT, Lyme disease is an infection caused by a microscopic organism carried in ticks and injected into the bloodstream following a tick bite. The most common tick involved is one that follows the deer population, called the deer tick. It is found where deer roam—in woodlands and fields, marshes, gardens and even beach areas. Seen worldwide, in the United States the infection is concentrated in southern New England, south-eastern NY, NJ, Delaware, Eastern PA, Minnesota and Wisconsin, though even within a particular state infection rates vary widely from county to county.
The likelihood of becoming infected after a deer tick bite depends upon several factors: the percentage of ticks in that area that are themselves infected, the life stage of the tick and the time the tick has spent feeding on an individual. It takes between 36 and 48 hours in children and 48 and 72 hours for adults for a tick to insert itself into the skin to begin feeding. Fortunately 75 percent of ticks are spotted and removed before 48 hours, so the risk of getting infected isn't high. In fact, overall, only one to two percent of bitten individuals get Lyme disease.
The signs and symptoms of Lyme disease are divided into early and late stages, but which symptoms are present varies among persons. The earliest signs show up in the skin, at the site of the bite. Usually between one and two weeks later, a characteristic rash forms in two-thirds of infected children. The rash can be itchy, painful or neither, uniformly red or with a clear, target-like center. The rash spreads outwards from the original site and can get very large, fading away in one to two weeks or longer. Fever, headache, fatigue and muscle aches can be present with this initial rash, or may appear later in the early stage as the organism spreads throughout the body. A second similar but smaller scattered rash can be seen during this phase, as well as headache, neck pain, swollen lymph nodes and conjunctivitis. Rarely, signs of meningitis are present. These secondary symptoms occur three to 10 weeks after the initial tick bite.
The late form of Lyme disease shows up as arthritis, and this can be months later. The knee is involved 90 percent of the time. The knee is painful and swollen, but gets better after a few weeks even with no treatment. Other joints can then become involved.