Lyme Disease and other Tick-Borne Illnesses
Pam Koenig, FNP
Publish Date: Fri, Jun 14th, 2013
Hooray! Spring has finally arrived and the warm sunny days entice us outdoors to garden, hike, fish, camp, play sports and relax on a hammock. Unfortunately, the pleasures of being outside also put us at for tick exposure. Deer ticks are a major concern as they carry several tick-borne illnesses such as Lyme disease, babesiosis and anaplasmosis.
Anna is 62 years old and an outdoor enthusiast. Last week she came into the clinic carrying a plastic bag in which a tiny dark tick was crawling. "I pulled this tick out of my big toe last night. Do you think it's a deer tick?" The bagged tick was solid dark brown with black legs, about the size of a sesame seed.
Lyme disease is the most common tick-borne illness in North America. In Maine it is caused by the bacteria borrellia burgdorferi and transmitted through a deer tick bite. According to the Maine Center for Disease Control (CDC), Lyme disease is increasing every year in all counties. A record high of 1100 cases was reported in 2012 and Lyme disease is already being reported for 2013. Lyme disease is most common in school-age children, middle-aged adults and adults over age 65. The prevalence of Lyme disease in Maine is 8 times greater than the national average and last month the Maine CDC released a state-wide health advisory to alert the public about this health concern.
Deer ticks are found on white-tailed deer and white-footed mice. Nymphs and adult females carry the bacteria that cause Lyme disease and typically bite humans when temperatures are above freezing. The greatest risk for a deer tick bite is April to August and through the fall. Ticks are found close to the ground and cannot jump or fly. They are attracted to human body heat and the carbon dioxide we exhale. Ticks land on humans when we brush directly against them; they bite and attach to our skin so they can feed on blood. A tick must have fed on its human host for at least 24 hours for infection to occur.
Deer ticks are small - nymphs are the size of a poppy seed and unfed adults are the size of a sesame seed. Adult females have a reddish-brown tear shaped body with a dark brown hood, and adult male deer ticks are solid black or dark brown. Deer ticks prefer wet, marshy, brushy or wooded areas and river beds. However, if you have deer grazing in your yard, garden or pastures, deer ticks will be in plentiful supply.
Dog ticks are also common to this area and are easily differentiated from deer ticks. Adult female dog ticks bite and feed upon dogs and humans alike. Unfed dog ticks are about the size of a watermelon seed, have a dark brown body, a white dot or shield behind the head, or white 'racing stripes' down the back. Dog ticks are abundant in the summer and prefer dry open habitats like fields and grass. If you find ticks in the spring or fall, chances are they are probably deer ticks.
Lyme disease causes an inflammatory response in the body. Early symptoms may include an expanding red bull's eye rash that occurs within 3-30 days, muscle and joint pain, fatigue, chills, fever, headache and swollen lymph glands. As the infection progresses symptoms such as numbness or tingling, irregular heart rhythms, fatigue, shortness of breath, and drooping of one side of the face may develop. Late symptoms include recurrent joint pain and swelling, brain inflammation, confusion, worsening headaches and possibly facial paralysis.
Lyme disease is treatable and preventable and most people recover after receiving effective treatment. A single dose of antibiotic within 72 hours of the bite may prevent the disease with ongoing monitoring for 30 days recommended. For those who develop a bull's eye rash without ever seeing a tick bite, a longer course of antibiotic is indicated. It is possible to become re-infected with Lyme disease and symptoms can persist over time. A blood test can determine if the infection is in the early or late stages.
"My toe is pink where the tick was embedded and a little swollen but it doesn't hurt" said Anna. "I don't know how long the tick was there - do you think I have Lyme disease?" The site of the bite did not have the classic 'bulls eye' rash of Lyme disease but was pink, flat and warm. Given Anna's penchant for the outdoors and the fact that she lives in an area known to support deer tick habitat it was prudent to treat with an antibiotic to prevent Lyme disease.
Other diseases carried by deer ticks in Maine include anaplasmosis and babesiosis. Co-infections with Lyme disease can occur as a single deer tick may carry multiple pathogens. Symptoms of anaplasmosis include fever, chills, severe headache, malaise and body aches. Symptoms of babesiosis include extreme fatigue, aches, fever, chills, sweating, and dark urine. There is no data showing antibiotic treatment within 72 hours as preventative for anaplasmosis and a single antibiotic dose will not have an effect on babesiosis. This is the reason for ongoing monitoring for 30 days after early treatment for a deer tick bite.
By far the best approach to Lyme disease is prevention. Dress appropriately and use caution in tick infested areas – tuck pant legs into socks and wear protective clothing. Use insect repellent such as DEET, oil of lemon or eucalyptus and thoroughly wash and dry clothes worn outdoors. Perform daily tick checks including hair, nape of the neck, ears, armpits, groin, and between toes.
If you find a deer tick embedded in your skin, remove the tick promptly and properly, using tweezers or a tick spoon. Place tweezers around the mouth of the tick as close to the skin as possible. Pull the tick upward with gentle, slow, steady pressure until it lets go. Place the tick in a sealable plastic bag and dispose of it outside your home. Do NOT twist, poke, squash or burn the tick and don't smother it with petroleum jelly or kerosene. Try to identify the type of tick, date and location of the bite and how long it was attached. Clean the bite area with soap and water, rubbing alcohol or hydrogen peroxide. If a rash or flu-like symptoms appear, contact your health care provider as soon as possible after being bitten. Remember – the risk of disease is considerably reduced if the tick is removed within 36 hours and treatment is received within 3 days.