wildlife and zoo assay data sheet

Babesia species

Test code: X0020 - Qualitative detection but not differentiation of most reported species of Babesia, such as Entopolypoides (Babesia) macaci and B. microti, by real time polymerase chain reaction

Babesiosis is an illness caused by the parasite Babesia which is an intra-erythrocytic protozoan. This parasite can infect a wide range of mammals including primates, dogs, cats and various livestock. The parasite can also be transmitted to humans by ticks.  Infected animals and humans may develop fever, chills, sweating, myalgias (muscle aches), fatigue, hepatosplenomegaly (enlargement of the liver and spleen) and hemolytic anemia.

Currently, more than 100 species of Babesia have been reported but only a few have been identified as causing human infection. Babesia microti and Babesia divergens have been identified in most human cases, but variants (considered different species) have also been identified recently. There is only scanty knowledge about the occurrence of Babesia species in malarial areas where Babesia can easily be misdiagnosed as Plasmodium, the agent of malaria.

Babesia-like parasites of the genus Entopolypoides macaci have been reported to infect nonhuman primates. Analyses of the small-subunit rRNA (SSUrRNA) sequences of E. macaci and serological and epidemiological data suggest that the genus Entopolypoides is synonymous with that of Babesia.  In various primate centers, natural infections with this parasite have been reported in baboons (Papio cynocephalus), cynomolgus macaques (Macaca fascicularis), and rhesus macaques (Macaca mulatta).  Sub-clinical infections with this parasite may exist in various primate centers and breeding farms; the use of these infected animals could pose a significant problem to research studies and occupational hazard to workers who handle these animals.

Infections with this parasite are common in livestock. For example, bovine babesiosis is an important tick-borne disease caused by B. bovis, B. bigemina and B. divergens. Currently, control methods such as chemotherapy, premunition and vaccination with attenuated parasites are used to avoid economic losses caused by Babesia infection.

Blood smear examination is considered to be the “gold standard” for diagnosis of babesiosis.  However, parasite visualization in blood smears may be difficult in cases where small numbers of parasites are present in the peripheral blood (Böse et al., 1995), and Babesia can be difficult to differentiate visually from Plasmodium species. Serological detection is of limited value because of the existence of multiple species of Babesia.  Many animals have been previously exposed to this parasite and have developed antibody responses, so that a positive serological result may not reflect a recent infection.  Currently, molecular detection is considered to be the most sensitive and specific method to identify animals infected with this parasite (Costa-Júnior et al., 2006).

Utilities:

• Confirm the disease causing agent
• Environmental monitoring
• Ensure that animal populations are free of Babesia species
• Early prevention of spread of these parasites among a group of animals
• Minimize human exposure to these parasites
• Safety monitoring of biological products and vaccines that derive from susceptible animals

References:
Böse, R., Jorgensen, W.K.,  Dalgliesh, R.J., Friedhoff, K.T. and De Vos, A.J. (1995) Current state and future trends in the diagnosis of babesiosis, Vet. Parasitol. 57 61–74.

Costa-Júnior, L.M., Rabelo, E.M.L., Filho, O.A.M. and Ribeiro, M.F.B.(2006) Comparison of different direct diagnostic methods to identify Babesia bovis and Babesia bigemina in animals vaccinated with live attenuated parasites. Vet. Parasitol. 139:231-  

Specimen requirements:  0.5 ml whole blood in EDTA (purple top) or ACD (yellow top) tube.

For specimen types other than those listed here, please call to confirm specimen acceptability and shipping instructions.

For all specimen types, if there will be a delay in shipping, or during very warm weather, refrigerate specimens until shipped and ship with a cold pack unless more stringent shipping requirements are specified. Frozen specimens should be shipped so as to remain frozen in transit. See shipping instructions for more information.

Turnaround time: 2 business days

Methodology: Qualitative PCR

Normal range: Nondetected