Babesiosis
Babesiosis is a parasitic disease primarily caused by the protozoan parasites Babesia microti and Babesia divergens, which are transmitted to humans through the bite of infected deer ticks. While many individuals may remain asymptomatic, some experience flu-like symptoms, including malaise, fever, chills, fatigue, and muscle pain, which can develop within one to nine weeks after exposure. Severe cases can occur, particularly in individuals with weakened immune systems or those without a functional spleen, leading to symptoms reminiscent of malaria. Treatment typically involves a combination of antiparasitic medications and antibiotics, though those with mild symptoms may recover without intervention. Babesiosis is increasingly recognized as an emerging infection in the northeastern United States, with preventive measures focusing on protective clothing and insect repellents in tick-heavy environments. Despite its historical documentation dating back to the late 19th century, no vaccine currently exists, making awareness and prevention crucial for at-risk populations.
Babesiosis
ALSO KNOWN AS: Human piroplasmosis, Nantucket fever
ANATOMY OR SYSTEM AFFECTED: Blood, kidneys, liver, respiratory system
DEFINITION: A parasitic disease that is transmitted to humans by the bite of an infected tick.
CAUSES: Parasitic infection
SYMPTOMS: Malaise, fatigue, chills, fever, sweating, muscle and joint pain, jaundice, anemia, shortness of breath
DURATION: Days to months
TREATMENTS: Combined antiparasitic and antibiotic therapy, supportive care
Causes and Symptoms
Babesiosis is caused by a protozoan parasite that infects livestock and domestic animals and, more rarely, humans. Babesia microti (in the United States) and Babesia divergens (in certain parts of Europe) are the species more often associated with disease in humans. The parasite, which destroys red blood cells, is spread by the bite of infected deer ticks (in the United States), which also transmit Lyme disease. Ticks become infected with the Babesiaorganism while feeding on infected deer, mice, or voles. The can also be transmitted by blood transfusions, although this mode is uncommon.
Many people infected with Babesia have no symptoms of illness, even though infection may persist for months to years. Others experience flulike symptoms, such as fatigue, poor appetite, fever, chills, sweating, headaches, body aches, or even nausea. Symptoms usually manifest themselves after a one- to nine-week and may last for weeks. For people with a weak or who lack a functioning spleen, life-threatening, malaria-like symptoms may develop that include high fevers, severe (as a result of the abnormal breakdown of red blood cells), and jaundice.
Treatment and Therapy
People with no symptoms or only mild symptoms usually recover on their own. Otherwise, the standard treatment has consisted of the clindamycin and the antiparasitic drug quinine. More recently, therapy has included the antibiotic azithromycin and the antiparasitic drug atovaquone, which are more easily tolerated.
Transfusions may be given to replace the infected in severe cases associated with high levels of parasites in the blood. For complications such as very low blood pressure, breathing difficulties, and kidney failure, supportive care consists of vasopressors (to increase the blood pressure), mechanical ventilation, and dialysis.
Perspective and Prospects
The Romanian scientist Victor Babes was the first to document the symptoms of babesiosis in cattle in 1888. The American scientist Theobald Smith and his colleagues identified a protozoan as the cause of disease and the tick as the agent of in 1893. The first case of babesiosis in humans was reported in 1957 in a person whose had been removed.
In the United States, babesiosis is considered an emerging infection, especially in coastal areas of the northeastern United States and its offshore islands, where the first case was reported in 1969 from Nantucket Island, Massachusetts. According to the Centers for Disease Control and Prevention (CDC), cases have been reported in New England, New York, New Jersey, Wisconsin, and Minnesota. No is available to date. The best prevention is to wear protective clothing to cover the skin and to use insecticides to repel ticks when journeying through wooded, tick-infested areas.
Bibliography:
"Babesiosis." National Institute of Allergy and Infectious Diseases, Nov. 12, 2010.
"Babesiosis FAQs." Centers for Disease Control and Prevention, 1 June 2023, www.cdc.gov/parasites/babesiosis/gen‗info/faqs.html. Accessed 28 Mar. 2024.
Considine, Glenn D., ed. Van Nostrand’s Scientific Encyclopedia. 10th ed. 3 vols. Hoboken, N.J.: Wiley-Interscience, 2008.
Gelfand, Jeffrey A., and Edouard Vannier. “Babesiosis.” In Harrison’s Principles of Internal Medicine, edited by Anthony Fauci et al. 18th ed. New York: McGraw-Hill, 2012.
Montero, E. et al. "Retrospective Study of the Epidemiological Risk and Serological Diagnosis of Human Babesiosis in Asturias, Northwestern Spain." Parasites Vectors, vol. 16, no. 195, June 2023, doi.org/10.1186/s13071-023-05817-x. Accessed 28 Mar. 2024.
Mylonakis, Eleftherios. “When to Suspect and How to Monitor Babesiosis.” American Family Physician 63 (May, 2001): 1969–1974, 1976.
"Tick Bites." MedlinePlus, Apr. 29, 2013.