What is Lyme disease?

Lyme disease is spread by a deer tick. To spread the bacteria that causes Lyme disease to people, the tick needs to be attached to the skin for at least 24 hours. If the tick looks very swollen, that can be a sign that it was attached for long enough to spread the bacteria. You cannot get Lyme disease directly from another person.

My child was bitten by a tick! What should I do?

Here is what you can do if your child was bitten by a tick:

  1. Look at the tick to see what kind it is. Deer ticks are about the size of a sesame seed. They have black heads and red bodies.
  2. Check to see if the tick is swollen. Even if a tick is infected with Lyme disease, it does not always spread the bacteria when it bites. This is especially true if it was attached for a short time (less than 24 hours).
  3. To lower the chance that a tick will spread bacteria, remove it as soon as you see it. Use tweezers to grab the tick and pull straight away from the skin. If the mouth parts do not come out, that is okay. They will fall off over time.

I removed a tick from my child. Should I send it to a lab for testing?

Doctors recommend that you do NOT send ticks to a lab to be tested for Lyme disease. If a tick is infected with the bacteria, it often does not spread bacteria when it bites.

Even if the bacteria spread to your child’s blood, often the body’s immune system can often fight it off on its own without antibiotics. If you do send a tick in for testing, the results can take several days to come back. This is not helpful for the doctor in deciding whether your child needs treatment to prevent Lyme disease.

Can my child take antibiotics "just in case?"

In many cases, antibiotic treatment “just in case” is not safe or does not work well. If you know the tick has been attached to your child’s skin long enough, the doctor might prescribe one dose of an antibiotic called doxycycline to prevent Lyme disease. This is called prophylaxis. However, it is not 100% effective and only works if this dose is given within 72 hours (3 days). This antibiotic is typically not recommended for children under 8.

It is important to give antibiotics to children who have Lyme disease with symptoms. It is also important not to give antibiotics to children who do not have Lyme disease. Antibiotics can have bad side effects in the short-term. Some people are also allergic to antibiotics. Also, if a person takes antibiotics when they are not needed, bacteria can learn ways to fight against them. This is called antibiotic resistance. When bacteria become resistant, antibiotics cannot kill them anymore. Future infections are also harder to treat.

What can I do if I am worried that my child has Lyme disease?

Lyme disease can be tricky to diagnose because there is no blood test that can say for sure whether your child was infected. The best way to tell if your child has Lyme disease is by hearing about their symptoms and doing a physical exam. In the first stage of Lyme disease, your doctor can tell if your child has Lyme disease and needs antibiotic treatment based on their exam. At that stage, blood tests can be inaccurate. They do not help make the diagnosis.

If your child has signs of a later stage of Lyme disease, the doctor may order blood tests or other tests to help figure out if your child needs treatment with antibiotics.

How can I prevent Lyme disease?

The best way to prevent Lyme disease is to prevent tick bites. This means wearing light-colored clothing, long sleeves and tucking pant legs into socks or boots. Remove any ticks you see on clothing, skin or hair right away. It is also helpful to treat clothes with permethrin or use insect repellant with DEET.

What are other diseases spread by ticks?

There are two other common diseases spread by ticks in New England. These diseases are anaplasmosis and babesiosis. Anaplasmosis can be spread by both lone star ticks and deer ticks. Babesiosis can only be spread by deer ticks. For both of these diseases, a tick needs to be attached for at least 24 hours to spread the bacteria. Even though ticks can carry these diseases, it is NOT a good idea to send the ticks to a lab for testing.

As with Lyme disease, even if a tick carries an infection, it does not spread bacteria every time it bites. Not everyone who gets the bacteria in their blood will develop anaplasmosis or babesiosis. These diseases can go away on their own with few or no symptoms. There are no good treatments to prevent these diseases.

If your child has symptoms of anaplasmosis or babesiosis, their doctor might send blood tests to decide whether they need treatment. If your child does not have symptoms of either disease, they should not get blood tests or antibiotics.

Rev. 5/2018. Vandana Madhavan, MD, MPH, is the clinical director of Pediatric Infectious Disease and Immunodeficiencies at MGfC. She is also the director of the Pediatric Advanced Clerkship at Massachusetts General Hospital and Harvard Medical School. Caitlin Li, MD, is a pediatric resident at MGfC.