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What is Lyme disease? Lyme disease in North America is caused by the spirochete Borrelia burgdorferi which is transmitted to humans by ticks. The carrier has been identified as a deer tick. As it feeds, the tick infects its host with the spirochete. The tick acts as a vector and transmits the spirochete from animal hosts to humans. The animal hosts may include mice, deer, birds, various wild and domestic animals, and even humans. The spirochetes enter the skin or bloodstream through either saliva or fecal material deposited by the tick.
Transmission: Ticks may stay attached for hours or days at a time. In their nymphal state, the ticks cling to the underside of vegetation (tall grass, brush, sand dunes, lawns, or woods). The nymphs cannot fly so there must be direct contact between the nymph and the skin of the person. The nymphal tick is about the size of a poppy seed and the adult that of a sesame seed. Since they are so small, few people even remember being bitten. Transmission can take place any time of the year but the majority is in late spring and summer.
Signs and symptoms: About 70-80% of people infected develop the characteristic skin lesion, erythema migrans (EM), which occurs at the site of the tick bite 3 to 30 days after the tick has detached. A distinctive feature of the rash is that it 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 usually not painful. Fever, headache, joint and muscle aches usually accompany early disease. Patients with untreated Lyme disease may develop cardiac involvement, neurologic disease or migratory musculoskeletal pain. Late manifestations of Lyme disease include arthritis, typically of the knee, and various neurologic conditions. Lyme disease is based on symptoms, physical findings, and the possibility of exposure to infected ticks; laboratory testing is helpful in the later stages of the disease. Health Services is unable to perform lab testing in the summer so anyone concerned that they need a blood test should go to either Wilton Medical Arts Center or the Emergency Room.
Treatment: No vaccine is currently available to prevent Lyme disease. Most cases of Lyme disease can be treated successfully with a few weeks of antibiotics. The strongest indication for antibiotic use is in a highly endemic area when an engorged tick is attached for 48 hours or more.
Prevention: The best way to prevent Lyme disease is to avoid places where the tick is found. It takes 6-12 hours for a tick to attach its mouth to a host. If removed during this time, it will probably not affect its victim. Since transmission of B. burgdorferi is more likely with prolonged tick attachment, prompt removal of ticks can also prevent disease. -Avoidance of ticks and use of tick repellants such as DEET or picaridin, or the insecticide permethrin on clothing can prevent Lyme disease. Only DEET can be used on the skin, but never in high concentrations, follow the manufacturer’s directions.
-Preventive measures must be taken, especially those with increased contact in the outdoors and in endemic areas. It is advised to avoid wooded and grassy areas as much as possible April through October, avoid brushing against vegetation, and keep toward the center of walking trails.
-Long-sleeved shirts and long pants with cuffs tucked into socks should be worn. If you tuck long pants into socks and shirts into pants, be aware that ticks that contact your clothes will climb upward in search of exposed skin. This means they may climb to hidden areas of your head and neck if not intercepted first; spot-check clothes frequently. Ticks will be more easily spotted on light-colored clothing and enclosed shoes. Tick checks should be done on leaving any danger area and for those with prolonged exposure, checks should be done twice daily. This involves inspecting clothing as well as the body, especially the areas of thighs, buttocks, trunk, or areas with tight-fitting clothing.
-Keep long hair tied back, especially when gardening.
-Avoid sitting directly on the ground or on stone walls (havens for ticks).
-Upon returning home, clothes can be spun in the dryer for 20 minutes to kill any unseen ticks.
-A shower and shampoo may help to remove crawling ticks, but will not remove attached ticks. Inspect yourself carefully after a shower. Keep in mind that nymphal deer ticks are the size of poppy seeds; adult deer ticks are the size of apple seeds. Frequent tick checks should follow a systemic, whole body examination each night before going to bed. Performed consistently, this ritual is perhaps the single most effective current method for prevention of Lyme disease.
-You can reduce the number of ticks around your home by removing leaf litter, and brush and wood piles around your house and at the edge of your yard. By clearing trees and brush in your yard, you can reduce the likelihood that deer, rodents, and ticks will live there.
What if I find a tick on me? If you do find a tick attached to your skin, there is no need to panic. Not all ticks are infected, and studies of infected deer ticks have shown that they begin transmitting Lyme disease an average of 36-48 hours after attachment. Therefore, your chances of contracting LD are greatly reduced if you remove a tick within the first 48 hours. Remember, too, that nearly all of early diagnosed Lyme disease cases are easily treated and cured.
If a tick is found it should be removed. Do not use petroleum jelly, fingernail polish, alcohol, or a hot match to remove. These methods are ineffective and may cause more harm by causing the tick to release its infected material into the skin. The tick should be grasped firmly with tweezers as close to the skin as possible. Pull it out gently but firmly. Don’t grab its bottom or crush it, spirochetes may be injected if this is done. After removal of the tick, cleanse the area well with alcohol or betadine. It may be a good idea to save the tick in a jar with alcohol; label the jar with the date and time of the bite. Many labs are now analyzing ticks to detect the presence of spirochetes. The bitten area should be observed for several weeks and immediately report any rash or other symptoms. Even if there are no other symptoms for several weeks, the tick bite should be kept in mind for mysterious symptoms in the future.
What about family members and pets? If one family member develops Lyme disease, others are not at risk unless also bitten. Human-to-human transmission has not been noted. Although dogs and cats can get Lyme disease, there is no evidence that they spread directly to their owners. However, pets can bring infected ticks into your home or yard. Consider protecting your pet through the use of tick control products for animals.
Additional information regarding Lyme disease may be found at the following websites:
