Objective: The aim is to establish a unified version of the biological method for babesiosis detection in vivo.
Patients and methods: Materials and methods: samples (n=257) of biological material of different origin were examined. These included: blood samples from patients (n=6) and cattle (n=15); salivary gland homogenates (n=28) from 147 imagoes of ticks of the family Ixodidae, 32 imagoes of Ixodes ricinus and 115 imagoes of Dermacentor reticulates; spleen homogenates (n=63) from mouse-like rodents (Muridae) of the genera Myodes, Microtus, Apodemus and Sylvaemus. In order to cultivate in vivo Babesiae of the species B. microti, Syrian hamsters were infected with spleen homogenates from mouse-like rodents; for cultivating the B. divergens species Mongolian gerbils and nonlinear white mices were infected with blood samples from patients and cattle and salivary gland homogenates from ixodic ticks. The technology of modeling was based on the group specificity (differences in susceptibility to parasites and in parameters of morbidity) of the animals, involved in the experiment (Syrian hamsters, Mongolian gerbils, nonlinear white mices).
Results: Results: Experimental animals were contaminated by means of intraperitoneal inoculation of 0.3 ml samples of biological material (infected with Babesiae). The animals were infected next day following a day of their preinoculation preparation. The marker parameters for the functional state of experimental animals were as follows: preterm death; appearance and development of clinical-laboratory signs of disease (hypo- or adynamia, loss of appetite, inertness/absence of reactogenicity to tactile/acoustical stimulation, postural changes, wetting of fur, pronounced lameness, flatulence, loss of ≥ 25% of body mass) in them; parasitaemia, histodestruction, cellular detritis. Parasitaemia was detected every two days (beginning with day 8 from the moment of inoculation) by reserves of light and luminescent microscopy. In case of the positive result (revealing of haemoparasites with Babesia spp.-like morphological and tinctorial signs) the verification of Babesiae with their more precise specific identification was performed using the technique of polymerase chain reaction (PCR). Preliminary detection of morbidity parameters in each experimental animal with the artificially created immunocompromised state became an obligatory moment of the described experiment.
Conclusion: Conclusions: The biological method for detecting Babesia spp. in vivo was improved by the author. This result was achieved by using a double reservoir (Syrian hamsters, Mongolian gerbils and nonlinear white mices with an increased level of susceptibility to parasites) followed by the immunocompromise formation. The use of the improved version of biological method increased the total rate of revealing of Babesiae, therewith creating an objective basis for optimizing the available ways of detection and study of Babesiae in vivo.
Keywords: Mongolian gerbils; Syrian hamsters; babesiosis; biological method; detection; nonlinear white mices.