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"How does babesiosis spread?"

ZocdocAnswersHow does babesiosis spread?


I see that it's a blood parasite. Can humans get it too? I'm a 28 year old farmer. It looks horrible.


Babesiosis is an infectious disease caused by a protozoan parasite of the genus babesia. This parasite invades red blood cells and eventually causes them to rupture. The spectrum of disease ranges from totally asymptomatic all the way to severe life-threatening infection. In cases of mild infection, patients typically experience gradual onset of fatigue, malaise, and weakness. Another relatively constant symptom of babesiosis is intermittent (or sometimes sustained) high fevers, accompanied by chills, sweats, and headaches. Because the parasite infects the red blood cells and eventually causes their destruction, a prominent feature of the disease is anemia, or low red blood cell counts. A small minority of cases of babesiosis can be very severe resulting in prolonged hospitalization or even death. These cases are associated with more virulent strains of the parasite and a higher infectious burden of parasites in the blood stream. The complications of severe disease include acute respiratory distress syndrome (ARDS), coagulation abnormalities such as low platelets or disseminated intravascular coagulation (DIC), heart failure, kidney failure, and heart attacks due to low red blood cell counts. Most reported cases of human babesiosis occur in the United States and Europe. As with all parasitic diseases the mode of transmission is closely tied to the life cycle of the infectious organism. Babesia species are typically caried by a vertebrate host reservoir and the vectors which transfer the organism are ticks. For example, babesia microti is the predominant species that causes babesiosis in the United States. The organisms that serve as the reservoirs for this organism are white tailed deer and the white-footed mouse. The ixodes scapularis tick (or deer tick) feeds on these animals and contracts the babesia organism, but is not itself infected by the disease. Human infection is purely incidental and not an important part of the life cycle of the babesia organism. When a deer tick feeds on a human host, the babesia infection is transmitted and the human contracts babesiosis. Babesiosis is endemic to the northeastern united states, particularly to the islands off the coast of southern New England. Although not an especially common infection, babesiosis has potentially serious implications and if you think you may have been infected or if you have any symptoms of the disease, you should go to see a doctor as soon as possible. Either a primary care doctor or an infectious disease specialist would be capable evaluating and treating you for babesiosis.

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