TICKS AND LYME DISEASE IN THE NATIONAL PARKS LYME DISEASE Lyme disease is an illness caused by corkscrew-shaped bacteria called spirochetes that are transmitted to people by tick bites. Not all ticks carry the disease. However, local infection rates can be quite high in some tick species. The disease gets its name from the town of Old Lyme, Connecticut, where it was first described in 1975. 2 In 1984, there were 1,498 cases of Annals of Internal Medicine, June 1977 Vol. 86, No. 6, Lyme disease reported from 22 states to the pp. 685-698, Dr. Allen C. Steere, et. al. Centers for Disease Control. Over 90% of all reported cases have been acquired in seven states: the Northeast seaboard (Connecticut, Massachusetts, Rhode Island, symptoms. If left alone, these early New Jersey, and New York) and the upper symptoms may disappear, but more serious Midwest (Wisconsin and Minnesota). An problems may follow. increasing number of cases have also been reported from California and Oregon, Some patients apparently have no Texas, and parts of the Southeastern further symptoms, especially if treatment is United States. sought. However, for others later complications can be quite severe. The most common later problem is arthritis, usually of the large joints (e.g., knees, hips, ankles). This can occur a few weeks SYMPTOMS AND to over a year after the tick bite, and can recur several times over the following years TREATMENT (occasionally, it can become chronic). Meningitis may also occur, with fever, A characteristic rash or lesion called severe headache and stiff neck weeks to erythema chronicum migrans (ECM, for months after the tick bite. Other short) develops a few days to a few weeks complications include neurological after the bite of an infected tick. The rash problems such as numbness, tingling in the generally looks like an expanding red ring extremities, loss of concentration and with a clear center, but it can vary from a ability to have memory retention, loss of blotchy appearance to red throughout. confidence and withdrawal, lethargy, Sometimes there are two or more lesions. and/or Bell's palsy (loss of control of one Unfortunately, some patients never get a side of the face), or cardiac symptoms such rash, making diagnosis difficult. At about as heart palpitations or heart block. this time, flu-like symptoms may appear Remember, some patients do not get a along with headache, stiff neck, fever, rash, and progress directly to these later muscle aches, and/or general malaise. It is manifestations. Treatment of later important to seek medical attention if any symptoms is more difficult than for early of these symptoms appear. Tell the symptoms and is less often successful. physician that you have been or may have Therefore, early treatment is very been bitten by a tick. Timely treatment important. If you develop any of these (with appropriate antibiotics) can cure the symptoms after being bitten by a tick, or disease or lessen the severity of any later after visiting an area where Lyme disease is common, see a doctor and mention the The common American dog tick possibility of Lyme disease. Don't put it (Dermacentor variabilis) does not transmit off! Lyme disease, but carries other diseases such as Rocky Mountain Spotted Fever. TICKS THAT CARRY LYME DISEASE The deer tick (Ixodes dammini) is responsible for most cases of Lyme disease in the northeastern and northcentral United HOW TO AVOID States. Adults are found in grassy, TICK BITES shrubby, and woodland habitats in the fall and spring, and even on warm winter When in tick habitat (grassy, brushy, days. They feed mostly on white-tailed or woodland areas), several precautions can deer, Odocoileus virginianus, but will also minimize your chances of being bitten by a attack other large mammals. If infected, tick. they can transmit the Lyme disease spirochete to their hosts. After engorging, Tuck your pant legs into your socks. females apparently drop to the ground to Tuck your shirt into your pants. Deer lay eggs. The larvae that hatch from the ticks grab onto feet and legs and eggs seek hosts from July through then climb up. This precaution will September. They are very small and keep them on the outside of your difficult to spot. clothes, where they can be spotted and picked off. Larva Nymph Adult Wear light colored clothing. Dark Some of the larvae acquire the Lyme ticks can most easily be spotted disease spirochete while feeding on against a light background. infected hosts. After engorging, they molt Inspect your clothes for ticks often into nymphs, which appear the following while in tick habitat. Have a spring and early summer (May through July). Nymphs that were infected as larvae companion inspect your back. can now transmit spirochetes to their new Wear repellents, applied according to hosts. Both immature stages attach to a variety of small mammals, but mostly to label instructions. Application to white-footed mice, Peromyscus leucopus. The shoes, socks, cuffs, and pant legs are nymphs molt into adult ticks, completing most effective against deer ticks. the life cycle. In the north, therefore, a generation apparently lasts two years. Inspect your head and body However, some individuals may complete thoroughly when you get in from the the life cycle in one year, especially in field. Have a companion check your southern parts of the range. back, or use a mirror. The lone star tick (Amblyomma When working in tick habitat on a americanum), a common southern species, regular basis, do not wear work and the California black-legged tick (Ixodes clothing home. This will reduce the pacificus), a western tick, can also transmit chances of bringing ticks home and Lyme disease. exposing family members. WHAT TO DO IF BITTEN BY Prepared for the NPS by: A TICK Howard S. Ginsberg Center for Coastal and Environmental Remove the tick as soon as possible. Studies The easiest method is to grasp the tick Rutgers-The State University of New with fine tweezers, as near to the skin as Jersey you can, and to gently pull it out. You New Brunswick, NJ 08903 may want to save the tick in a small jar for later identification. Check to see whether Jorge L. Benach the mouthparts broke off in the wound. If they did, seek medical attention to get Edward M. Bosler them removed. If you get any symptoms of Lyme disease in the following week to State of New York Department of Health Health Sciences Center several months, see a physician immedi- State University of New York at Stony ately. Be sure to tell the doctor that you Brook were bitten by a tick. A blood test can help Stony Brook, NY 11794 determine if you have been exposed to Lyme disease.