Babesia divergens - Microscopic exam; Molecular diagnostics (PCR).
Babesia divergens is a protozoan parasite of the genus Babesia, family Babesiidae, which causes bovine babesiosis (Redwater also known as fever), but they have also been cases of babesiosis in humans. Babesia divergens is widespread in Europe and North Africa.
The life cycle of this organism involves an intermediate host where mature, usually infected ticks Ixodes ricinus, which transmit the infection during feeding releasing sporozoites into the bloodstream of the animal. Although the major carrier is the tick, Babesia divergens can be transmitted through the use of needles or surgical material vaccinations.
Babesia divergens develops in erythrocytes of the host, which can be visualized as round or oval shaped bodies or ring, with an approximate length of 1.5 to 1.9 .mu.m. In erythrocytes of humans, the parasite is significantly higher than in cattle, with a length of 1.9 microns. Inside red blood cells, Babesia divergens begins to divide, becoming the merozoite form that could be taken with erythrocytes by a new tick for food. After ingestion by ticks, Babesia divergens sexual reproduction begins (gamogony), which after the formation of the zygote and the oocyst, resulting in numerous sporozoites that accumulate in the salivary glands of ticks. In some cases, the parasite can remain in the environment by livestock that has recovered from an infection. In these cases, the parasitaemia may persist for several years after the initial infection, which can be a source of transmission for new infection of ticks. Furthermore, Babesia divergens can be transmitted transplacentally.
In animals, clinical signs include fever, anemia, jaundice, anorexia, depression, weakness, increased heart and respiratory rate, diarrhea, hemoglobinuria and splenomegaly, which can cause death within a few days. In the terminal phase, the animal may have weak pulse, severe jaundice, constipation and dehydration. In general, death is due to renal heart failure, liver or. In some cases, the animal may recover and eliminate the parasite from your body.
While young animals (up to 2 years old) are fully susceptible to infection with Babesia divergens, many of them are resistant to disease. As a result, in areas where there is a high infection by the microorganism, most of the animals have been infected during this period of resistance and therefore become immune without showing clinical symptoms. In cattle older, repeated exposure to infected ticks strengthens immunity, so that clinical cases are usually rare.
In people, after an incubation period of 1 to 3 weeks, affected individuals may have generalized weakness and malaise. In the acute phase, there may be hemoglobinuria, jaundice, persistent fever, chills, intense sweating, headache and myalgia, as well as lumbar and abdominal pain. Furthermore, vomiting and diarrhea may occur. In severe clinical cases, affected individuals may have symptoms of shock, renal failure and pulmonary edema.
Recommended tests for diagnosis:
The diagnosis is based on microscopic identification of parasites in blood smears immunosorbent assay (ELISA), or molecular diagnostic methods (PCR).
Tests in IVAMI:
- Microscopic examination for observation of parasites in blood smears.
- Molecular diagnosis (PCR), to detect DNA of Babesia divergens.
- Whole blood collected with EDTA (2 to 5 mL).
Preservation and shipment of sample:
- Refrigerated (preferred) for less than 2 days (for microscopic examination and / or molecular diagnostics).
- Frozen: more than 2 days (for molecular diagnostics).
- Microscopic examination: 24 hours.
- Molecular diagnosis (PCR): 24 to 48 hours.
Cost of the test: