Health Matters: Ticks and tick-borne diseases
The tick-borne illnesses most commonly encountered in our community are Lyme disease and anaplasmosis. Both of these infections are caused by bacteria and are treated with antibiotics. These infections tend to present with symptoms as early as one week following the bite. Typically, we see patients with symptoms between two and four weeks following the bite.
Symptoms are similar for both infections and can include fatigue, loss of appetite, headache, neck stiffness, muscle or joint pain, swollen lymph nodes, and/or fever. There are some distinguishing features between the two infections, however. Anaplasmosis tends to cause higher fevers, less joint and muscle aches, possible cough, confusion and more weakness. Lyme is often described to health caregivers by patients as experiencing "flu" in the summer due to the extreme fatigue, muscle and joint aches and headache. The classic bull's eye rash is seen with Lyme disease, but is not always present. In fact, this rash occurs only 15 to 25 percent of the time. Thus, you do not need a rash to have tick-borne illness.
Patients may also experience redness, itching and warmth at the site. This can represent a local allergic reaction to the tick and may not represent infection. A local reaction may last for several days following the bite. It is a good idea to get these checked if you are unsure. Typically, a bite reaction is less than 5 cm (2 inches) in size. You may be asked to watch a tick bite spot for signs of enlarging over a few days or return to your practitioner's office for recheck before treating with antibiotics right away.
After a tick bite, antibiotic prophylaxis (two pills of doxycycline given as one dose only) is started for patients 8 years and older if seen in office within 72 hours of removal of an engorged tick. Clinical guidelines recommend starting prophylaxis if the tick was attached for 24 or more hours. This is the amount of time expected for ticks to become engorged with blood, which causes them to expel the bacteria into the bite. There is no approved prophylactic treatment for patients 7 years and younger. For these patients, we recommend careful observation for the signs and symptoms discussed above. Preventative treatment with doxycycline has only been studied for Lyme disease. It is unknown whether this strategy will prevent other tick-borne illnesses.
Tick bite prevention includes avoiding skin exposure by wearing long sleeves and long pants tucked into socks when outside. Ticks are found in tall grasses and wooded areas. DEET applied to the skin and Permethrin applied to clothing are both effective tick repellants.
Ticks found on the body can be removed with tweezers. Place tweezers at the head of the tick and pull straight back without twisting. The skin should be cleansed with soap and water after removal. Aftermarket tick removal devices are similarly effective. Occasionally, the tick breaks during the removal process, leaving the jaws embedded in the skin. These do not require further removal and will expel spontaneously without further treatment. Retention of these pieces is not found to increase incidence of infection.
The tests for Lyme disease are only accurate after the body has had sufficient time to develop antibodies. This may take two to four weeks. Therefore, your health caregiver may not feel it is necessary to test you before starting treatment, especially if you have classic symptoms and known tick bite. Tests for other tick-borne infections can detect infection right away, but again, classic symptoms may prompt your practitioner to treat without testing, especially with such a high rate of tick-borne infection in our community. Patients that develop early Lyme disease or anaplasmosis are generally treated with an oral antibiotic for two to three weeks, such as doxycycline, amoxicillin, cefuroxime-axetil.
If you meet criteria for antibiotic prophylaxis or have symptoms of tick-borne illness, you should be evaluated by your primary care provider.
This column was written by Erica Gallen, F.N.P., Southwestern Vermont Medical Center (SVMC) ExpressCare, with help from Marie George, M.D., infectious disease specialist with SVMC Multispecialty Practice, and Trey Dobson, M.D., chief medical officer at SVMC and medical director for Dartmouth-Hitchcock Putnam Physicians. "Health Matters" meant to educate readers about their personal health, public health matters and public policy as it affects health care. For more stories like this one, visit svhealthcare.org/wellnessconnection. For health system news and updates, follow facebook.com/svmedicalcenter.
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