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Lyme Disease

This fact sheet answers frequently asked questions about Lyme Disease.

Lyme disease is an illness caused by bacteria.

The basics

What is Lyme disease? 

It spreads to people and animals through tiny infected deer ticks. It is the most frequently reported tick-borne illness in the United States.

Where is Lyme disease found?

You can find deer ticks everywhere in Massachusetts. They are especially populous in coastal areas, islands, and the Connecticut River Valley. In Boston, you can find ticks in grassy, brushy, or wooded areas. The disease is most likely to spread between spring and early autumn, when ticks are most active.

How is Lyme disease spread?

Deer ticks cling to plants near the ground in brushy, wooded, or grassy places. These ticks are quite small and climb onto animals and people who brush against the plants. Very young ticks, called larvae, pick up the bacteria that cause Lyme disease by biting infected animals. Slightly older ticks, called nymphs, are the size of a poppy seed and are the stage most likely to bite humans. Adult deer ticks can transmit the disease, but they are not as great a risk as nymphs. Adults are less likely to bite humans because they are easier to see and remove.

Ticks live for 2 years and can infect animals as well as people. Not all ticks carry Lyme disease, and a deer tick bite does not mean that you will always get the disease. The tick must usually attach for at least 24 hours to pass on the bacteria. Removing the tick promptly will greatly decrease your chances of infection.


What are the symptoms of Lyme disease?

Early stage (days to weeks):

An early symptom of Lyme disease is usually a rash where the tick attached. The rash appears between 3 to 30 days after the bite. It often starts as a small red area then spreads, clearing up in the center so it looks like a donut. However, the rash may not always appear like this. Flu-like symptoms, such as fever, headache, stiff neck, sore and aching muscles and joints, fatigue and swollen glands are also common in the early stages of Lyme disease.

Although these early symptoms often go away by themselves after a few weeks, the person may still be infected. The rash may come back in some people in other places on their bodies, and some will experience more serious problems. Early treatment with antibiotics can clear up the rash within days and is important to prevent more serious problems from occurring later on.

Later stages (months to years):

People with Lyme disease can develop late-stage symptoms even if they never noticed a donut-shaped rash. Up to 60% of people with untreated Lyme disease get arthritis that comes and goes. Some people who don't get treatment develop nervous system problems. The most common problems include meningitis, facial weakness, general weakness, and pain. These symptoms can last for months, often shifting between mild and severe. In rare cases it can affect the heart with changes in the heartbeat.


How can I prevent Lyme disease?

The best way to prevent Lyme disease is to avoid areas where you are likely to find deer ticks. In general you can keep tick numbers low by reducing cover and shade, keeping grass mowed, removing leaf litter and trimming shrubs and trees. Other precautions to take:

  • Wear long sleeved shirts and long pants and tuck your pant legs into your socks
  • Light colored clothes can help you spot the ticks on your clothes before they reach your skin
  • Stay to the middle of paths when in a heavily wooded area
  • Use insect repellants containing DEET on exposed skin.  Read labels carefully. Use products with no more than 30% DEET. Do not use insect repellents on infants. Wash skin with soap and water after returning indoors
  • There are others insect repellent products approved by the EPA for ticks other than DEET. Visit the EPA to find the right repellent for you
  • Always check yourself and your children for ticks after visiting a high risk area

Click here to learn more about tickborne diseases.

What should I do if I find a tick on myself, my child or my pet?

Remove any ticks promptly using fine point tweezers:

  • Exam pets for ticks
  • Do not squeeze or twist the tick. Grasp it close to the skin and pull straight out with the steady pressure. Other methods such as using a match, petroleum jelly, or kerosene are not recommended
  • Clean the skin around the bite with soap and water or a disinfectant
  • Mark the date and location of the bite for future reference
  • If you develop a rash, see your health care provider


How is Lyme disease treated?

Prompt treatment of early symptoms with antibiotics is an important step to prevent later, more serious problems. Talk with your health care provider about the treatment of Lyme disease.

Is there a human vaccine for Lyme disease?

A human vaccine for Lyme disease is not currently available.

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