What is the Babesia Parasite?
Babesia is a single-celled parasite that infects the red blood cells. The most common strain known to cause illness in the United States is Babesia microti. Infection with Babesia is called babesiosis.
The parasite is typically transmitted to people through the bites of certain ticks. Although uncommon, it can also be transmitted by packed cell transfusion and via the transplacental route from mother to child.
In the United States, Babesia is usually transmitted by the bite of Ixodes scapularis (deer ticks). The nymph stage of the tick, which is about the size of a poppy seed, is the most likely to cause infection.
Ticks carrying the Babesia parasite are the most common in the Northeast and upper Midwest. Diagnosis rates tend to peak during the warm months, when the ticks are most active.
Many of those infected with Babesia don’t have any symptoms. Effective treatment is available for those who are diagnosed with babesiosis.
What Are the Symptoms of Babesiosis?
The most typical signs and symptoms of babesiosis in otherwise healthy people are usually mild and flu-like: high fever, chills, sweats, headache, muscle or joint pain, loss of appetite, nausea, and fatigue. Less common symptoms are severe headache, abdominal pain, mood changes, skin bruising, and yellowing of skin and eyes.
If the infection remains undiagnosed and untreated, some patients may develop chest pain, shortness of breath, hip pain, and drenching sweats. Since Babesia infects blood cells, babesiosis can lead to hemolytic anemia, resulting from the destruction of red blood cells. Serious long-term complications include very low blood pressure, liver problems, and kidney and heart failure.
Babesiosis may manifest as a severe illness in patients who do not have a spleen or who have reduced immune function for some other reason, such as cancer or AIDS. Those with other serious health conditions and the elderly are also likely to experience symptoms that can possibly even be life-threatening.
How Is a Babesia Parasite Infection Diagnosed and Treated?
If your doctor suspects that you’ve been infected with Babesia based on your symptoms and history of visiting high-risk areas, they will order a blood test. The standard diagnostic technique of babesiosis is the examination of blood smears under a microscope to detect the parasite. Other conventional testing methods include polymerase chain reaction (PCR), serological testing, and culture techniques. The ELISpot test is a fairly new and especially effective way of detecting active Babesia infections.
Since babesiosis is caused by a parasite, it doesn’t respond to antibiotics alone. Successful treatment requires antiparasitic drugs, like those used for malaria. A combination of atovaquone and azithromycin is usually used to treat most mild to moderate cases. A potential alternative is clindamycin and quinine.
Treatment of severe illness typically involves azithromycin given intravenously and atovaquone orally, or clindamycin given intravenously and quinine orally. Extremely severe cases may require a blood transfusion.
Although babesiosis is normally efficiently treated, relapses can sometimes occur. If your symptoms resurface following treatment, you need to be treated again. Those with weaker immune systems may need to undergo a longer course of treatment.
Is There a Connection Between Babesiosis and Lyme Disease?
The same tick that carries the Babesia parasite can also be infected with the bacterium responsible for Lyme disease, Borrelia burgdorferi. The prevalence of coinfections in ticks ranges from 2% to 13%, and up to 20% of people diagnosed with Lyme are also infected with Babesia. However, babesiosis often goes undiagnosed.
The signs and symptoms of the two illnesses are quite similar to those of Lyme disease, but coinfection can exacerbate the symptoms of both. Co-infected patients are more likely to experience severe fatigue, headaches, sweats, chills, nausea, and depression than those with Lyme disease alone. It’s important to consider the possibility of a coinfection when diagnosing patients with either illness, because they both require different treatments.
How Do I Prevent Tick Bites, and What Should I Do if They Happen?
You can prevent contracting babesiosis and Lyme disease by taking a few simple precautionary steps in order to limit your exposure to ticks. If you’re visiting a wooded or meadow area where deer are present, wear long pants and long sleeves. It’s a good idea to tuck your pants in your socks for added safety. Treat your clothing with permethrin and spray a repellent containing DEET on your shoes, socks, and all exposed areas of your skin! Keep to cleared trails and always walk in the middle of the trail.
Once you’ve returned home, you should search yourself and any children for ticks. If you find a tick on someone’s skin, you must remove it as soon as possible. Use pointed, fine-tipped tweezers to grab the tick’s mouth parts close to the skin, and carefully pull the tick straight out. You should see your doctor if you have flu-like symptoms shortly after visiting a high-risk area, even if you don’t recall being bitten by a tick.