Patient education: Lyme disease (The Basics)

What is Lyme disease? — Lyme disease is an illness that can make you feel like you have the flu. It can also cause a rash or fever, as well as nerve, joint, or heart problems.

People can get Lyme disease after being bitten by a tiny insect called a tick. When a certain type of tick bites you, it can pass the germ that causes Lyme disease from its body to yours. But a tick can infect you only if it stays attached for at least a day and a half.

The ticks that carry Lyme disease feed on deer and mice. They are only about the size of a poppy seed when they are young, which is when they most often spread Lyme disease. They grow to about the size of a sesame seed as adults (figure 1). Ticks are found in tall grass and on shrubs, and can attach to animals and people walking by. Ticks cannot fly or jump.

What are the symptoms of Lyme disease? — Symptoms can start days or weeks after a tick bite. They include:

●A rash where you were bitten – The rash often appears within a month of getting bitten. It is red, but its center can be the color of your skin. It might get bigger over a few days. To some, it looks like a "bull's eye" (picture 1).

●Fever

●Body aches and pains

●Heart problems such as a slowed heart rate

●Headache and stiff neck

●Feelings of pain, weakness, or numbness

If a person is not treated, further symptoms can occur months to years after a tick bite. This is sometimes called "late" Lyme disease. Some people develop late Lyme disease without having any earlier symptoms. The most common symptom of late Lyme disease is pain and swelling of the joints, usually 1 or both knees. Some people can have other symptoms, such as numbness, tingling, or pain in the legs. They can also have skin problems, such as skin swelling or thinning, but this happens mostly in Europe.

Should I see a doctor or nurse? — Yes. If you have symptoms of Lyme disease, see a doctor or nurse. Some people don't know that they were bitten by a tick. Or they might not remember having a rash or other early symptoms.

Is there a test for Lyme disease? — Yes. Blood tests can show if you are infected with the germ that causes Lyme disease. But it takes time for the blood tests to turn positive. This means the tests won't work if you get them right after being bitten or when you have the early rash that goes with Lyme disease. Because of this, if you have a recent tick bite or the rash, you do not need a blood test for Lyme disease. If you have been ill from Lyme disease for more than a month, the tests work well.

If your doctor or nurse suspects you have Lyme disease, they will do an exam and ask you questions. The doctor or nurse will use this information (and your blood test result, if needed) to decide your treatment.

How is Lyme disease treated? — Lyme disease is usually treated with antibiotics. There are a few different types. Treatment with antibiotics should help your symptoms go away. Sometimes, symptoms improve quickly. Other times, it can take weeks or months for symptoms to go away.

What if I am pregnant? — If you are pregnant, talk to your doctor. Some medicines for Lyme disease are safe to take if you are pregnant, but others might not be.

Can Lyme disease be prevented? — The best way to prevent Lyme disease is to avoid getting bitten by a tick. But if you were already bitten, your doctor might give you an antibiotic. In some situations, this can reduce your chances of getting Lyme disease.

To try to avoid getting bitten by a tick, you can:

●Wear shoes, long-sleeved shirts, and long pants when you go outside. Keep ticks away from your skin by tucking your pants into your socks.

●Wear light colors so you can spot any ticks that get on your clothes

●Wear bug repellent that protects against ticks, such as a spray or cream containing DEET. But you should talk to your doctor or nurse about using DEET on children. For example, DEET should not be used on babies younger than 2 months, and experts suggest not using products with more than 30 percent DEET on other young children.

On your clothes and gear, you can use bug repellents that have a chemical called "permethrin."

●Shower within 2 hours of being outdoors if you think you have been in an area where there are ticks

●Put dry clothes briefly (for about 4 minutes) in a dryer after being outdoors

●Check your clothes and body for ticks after being outdoors. Be sure to check your scalp, waist, armpits, groin, and backs of your knees. If you have children, check them, too.

●If you live in a place that has deer or mice nearby, take steps to keep those animals away. Deer and mice carry ticks.

If you find a tick on your body or on your child, use tweezers to grab it. Then pull it out slowly and gently. After that, wash the area with soap and water.

You do not need to keep the tick. But knowing what it looked like can help your doctor decide about your treatment. See if you can tell:

●Its color and size

●If it was attached to your skin or just resting on your skin

●If it was big, round, and full of blood

You should see your doctor or nurse if you have a tick and you cannot get it off.

You should also call your doctor or nurse if you think you have had a tick attached for at least 36 hours (a day and a half). Then they can decide if you need to take a dose of an antibiotic to help prevent Lyme disease. Doctors only recommend antibiotics to prevent Lyme disease in some situations. It depends on your age, where you live, what kind of tick bit you, and how long it was attached.

If you or your child was bitten by a deer tick, you should watch the area around the bite for a month to see if a rash appears.

More on this topic

Patient education: Insect bites and stings (The Basics)

Patient education: Lyme disease symptoms and diagnosis (Beyond the Basics)
Patient education: What to do after a tick bite to prevent Lyme disease (Beyond the Basics)
Patient education: Lyme disease treatment (Beyond the Basics)
Patient education: Lyme disease prevention (Beyond the Basics)