What is babesiosis?

Babesiosis (say: bab-e-see-oh-sis) is a rare infection of the blood caused by a parasite that lives in some ticks. Deer ticks typically carry the parasite that causes this illness.

Babesiosis infections are more common in animals than in humans, but cases have been reported in parts of the United States. Babesiosis has been reported most often in the upper midwest and the northeastern areas of the country, especially along the coasts.

What are the symptoms of babesiosis?

Some people who have babesiosis may not have any symptoms. When symptoms do occur, they are often similar to symptoms of the flu and include:

• Fever (as high as 104°F)
• Chills
• Sweating
• Weakness
• Fatigue
• Joint and muscle aches
• Loss of appetite
• Headache

However, sometimes the illness can quickly become serious, and can even cause death, especially in people who have had their spleen removed, are elderly, have liver disease, have kidney disease or have weak immune systems (due to conditions such as the human immunodeficiency virus [HIV], acquired immunodeficiency syndrome [AIDS] and cancer). Babesiosis can affect people of all ages, but most people who get it are in their 40s or 50s.

Who gets babesiosis?

People who spend time in areas where ticks are common (either for work or recreation) are at higher risk of getting tick-borne diseases. Ticks usually wait near the top of grassy plants and low bushes for people or animals to brush up against their perch. Ticks will often crawl upward on people's clothes or bodies for up to several hours or more before attaching to the skin.

How can my doctor tell if I have babesiosis?

Your doctor will need to do blood tests to see if you have this illness. Your doctor might also do blood tests to look for other infections that ticks can carry.

How is babesiosis treated?

In people who have healthy immune systems and only mild cases of babesiosis, no treatment is typically needed. The body fights the infection on its own.

People who have a more severe case of babesiosis are usually treated with 2 types of antibiotics. If you develop shortness of breath or any other symptoms after you start taking the antibiotics, tell your doctor right away.

Some people who have very severe cases of babesiosis or weak immune systems need to go to a hospital to be treated.

How can I prevent tick-borne diseases?

The best way to prevent tick-borne diseases is to avoid being bitten by ticks. When you are outdoors, follow these guidelines:

1. Use tick repellents according to their instructions to help prevent bites. Use an insect repellent containing 20% to 30% DEET. Tick repellents that contain DEET can be put directly on your skin or on your clothing before going into tick-infested areas. Apply DEET sparingly to skin according to directions on the label. Don't apply it to the face and hands of children and don't use it on infants younger than 2 months of age. Repellents containing permethrin should be put only on clothing. Make sure to talk to your doctor before you use any tick repellent on your child. Your doctor can give you more information on what type and strength of repellent is safe to use.
   
2. Wear light-colored clothing that covers most of your skin when you go into the woods or an area overgrown with grass and bushes. This makes it easier to see and remove ticks from your clothing. Wear a long-sleeved shirt and wear pants instead of shorts. Tuck your pant legs into your socks or boots for added protection. Remember that ticks are usually found close to the ground, especially in moist, shaded areas. Check your entire body for ticks after you have been in tick-infested areas, and check your children and pets for ticks. Common tick bite locations include the back of the knees, groin area, underarms, ears, scalp and the back of the neck.
   
3. Remove any attached ticks as soon as possible. To remove an attached tick, use fine tweezers to grab the tick firmly by the head (or as close to the head as possible) and pull. Do not use heat (such as a lit match), petroleum jelly or other methods to try to make the tick "back out" on its own. These are not effective ways to remove a tick.
   
4. Wash the area where the tick was attached thoroughly with soap and water. Keep an eye on the area for a few weeks and note any changes. You should call your doctor if you develop a rash around the area where the tick was attached. Be sure to tell your doctor that you were bitten by a tick and when it happened. Only people who get sick and/or get a rash after being bitten by a tick need antibiotics. If you are bitten by a tick and don't get sick or get a rash, you don't need antibiotics.

During the months of May through September, stay away from places where ticks are common. This is especially important if you've had your spleen removed, if you have had an organ transplant or are taking immunosuppressant medicines (which weaken or suppress the immune system), if you have HIV infection, AIDS or other chronic conditions that affect your immune system.

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