Babesiosis: Symptoms, Diagnosis, Treatment and Prevention

Babesiosis is a rare and life-threatening infection of the red blood cells that’s usually spread by ticks. It’s caused by tiny parasites called Babesia. The kind that most often affects humans is called Babesia microti. They enter your bloodstream when you’re bitten by an infected deer tick.
Other ways babesiosis can spread include:
Babesiosis usually happens in the warmer months. Ticks carrying the parasite have been found in:
People have gotten this infection in other states, too, including:
It’s also been seen in Europe.
Signs of babesiosis start 1 to 8 weeks after you come in contact with the parasite that causes the disease. Sometimes you won’t notice any symptoms. If you do, they might include:
You also can get a condition called hemolytic anemia in which your red blood cells die faster than your body can make new ones. Symptoms of this can include:
Symptoms can be worse if you’re elderly, no longer have your spleen, or have a health condition or take medications that weaken your immune system.
If you notice any of these symptoms, see your doctor and be sure to tell them if you’ve traveled recently. Ticks can be the size of a poppy seed, so you may not know if you’ve been bitten by one.
Your doctor will order blood tests to check for signs of infection. This includes looking for Babesia in the blood under a microscope. They may also want to do other blood tests to rule out conditions with similar symptoms, such as anaplasmosis or Lyme disease, which is also caused by ticks. It’s possible to have Lyme disease at the same time as babesiosis.
If you don’t have any symptoms, you probably won’t need treatment. If you do, your doctor may prescribe a drug called atovaquone that kills microorganisms along with the antibiotic azithromycin. Another combination they may recommend is quinine with the antibiotic clindamycin.
The ticks that cause babesiosis typically have to stay on your body for 36 to 48 hours to cause an infection. Here are some ways to prevent one: