Dr. Jim Mitterando
What is the risk of Lyme disease from a tick bite and what is the best treatment for tick bites? Lyme disease is caused by bacteria transmitted to animals and humans by bites from hard-to-detect deer ticks. These ticks, about the size of a poppy seed when young, grow only to the size of a sesame seed and are much smaller than common dog ticks, which do not carry Lyme disease. What to do if you are bit
If a deer tick bites you, do not panic. The risk of transmission is low and depends how long the tick was feeding and if it is engorged with blood. If the tick was present for less than 72 hours and is not engorged with blood, there is less than a 1 percent chance of infection and antibiotics are not recommended for prevention. If a deer tick is present for more than 72 hours, or if it was engorged with blood your risk of developing Lyme disease increases. In that case, taking two Doxycycline pills one time may prevent infection. Doxycycline cannot be taken by children younger than 8 years or by pregnant or nursing mothers. In those instances, Amoxicillin may be useful. Removing a tick
To remove the tick use a pair of tweezers. Grasp the tick by the head and pull firmly. If parts of the head remain in the skin do not worry because the bacteria that cause Lyme disease are in the tick’s abdomen and not in the pincers. Don’t try to kill the tick or get it to loosen its grip by covering it with petroleum jelly, burning it with a hot match or rubbing it with alcohol or nail polish remover. Those methods don’t work. Watch for rash
The earliest sign of Lyme disease is a rash, which may appear 3 to 30 days after a tick bite. This rash, called erythema migrans, usually starts at the tick bite and expands to several inches in diameter. The center of the rash may become clear as it enlarges, creating a “bull’s eye” appearance. The rash may be warm, but usually is not painful. Often, people with the rash do not even notice they have been bitten. Most rashes from tick bites are not Lyme disease. Any insect bite may trigger an allergic, itchy reaction that may improve with antihistamines, such as Claritin or Benadryl. Allergic reactions usually occur within hours to days after the tick bite. If the rash becomes painful, it may be infected and require antibiotics. Summer flu without head cold Think Lyme disease or other tick-related illness, if you develop flu-like symptoms of fevers, aches, stiff neck and headache in the summer- time and you do not have any cold symptoms of cough, sore throat or nasal congestion. The flu symptoms, generally, occur after the rash. About 20 percent of infected people do not develop a rash and only have the flu-like symptoms. Other tick-borne illness such as babesiosis, erlichiosis, tularemia can also cause summer flu-like symptoms but are much less common than Lyme and are mostly seen on the Cape, Nantucket and Martha’s Vineyard. Lyme disease can spread to the nervous system causing Bell’s palsy (a condition that causes the face to droop) or, less commonly, meningitis. Low incidence of Lyme disease The anxiety about Lyme disease is out of proportion to the incidence of the illness. Fortunately, relatively few people contract Lyme disease. On the South Shore, Lyme disease occurs in about two in every 10,000 people per year. It is more common on Cape Cod, Rhode Island and especially Nantucket and Martha’s Vineyard. Prevention
If hiking, consider wearing long-sleeved shirts and long pants and tuck your pant legs into your socks or boots. Apply an insect repellent containing DEET to clothes or exposed skin, or one containing Permethrin to your clothes only. Contrary to popular claims, DEET is safe for pregnant women and infants two months and older. The FDA and CDC recommend DEET in these groups. Check yourself and your child’s skin and scalp for ticks and rashes. Check your pets for ticks, too. The Lyme vaccine is no longer available because of low demand and concerns about causing an increased risk of arthritis.
Dr. Jim Mitterando is a family doctor at Cohasset Family Practice and a staff member at South Shore Hospital in Weymouth.
Readers should send questions to: Ask the Doctor, The Patriot Ledger, P.O. Box 699159, Quincy, MA 02269-9159, or by E-mail to his attention at [email protected].
Questions of general interest will be answered in this column. The information in this column is not intended to diagnose individual conditions, and individual replies are not possible. Readers should see their own doctors about specific problems.
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