Authors

¹ Department of Parasitology and Invasive Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Poland;  ² Department of Parasitology, Institute of Zoology, Faculty of Biology, University of Warsaw, Poland;  ³ School of Life Sciences, University Park, University of Nottingham

Discussion

Babesia microti causes disease, babesiosis. Congenital invasions have been recorded in humans, dogs, livestock and laboratory mice. Our aim was to determine if vertical transmission of B. microti occurs in naturally-infected hosts. We sampled 124 common voles (M. arvalis), 76 root voles (M. oeconomus) and 17 field voles (M. agrestis) in the Mazury Lakes District (Poland). 113 embryos were isolated from 20 pregnant females. 11 pregnant females were kept in animal house until they had given birth and weaned their pups (n=62). Blood smears and/or PCR targeting the 18s rRNA gene were used for the detection of B. microti. Selected PCR products were genotyped (n=117). The highest prevalence was recorded in common voles (45.2%), then in root voles (39.5%) and field voles (17.7%). B. microti DNA was detected in 71% of pregnant females of common voles, 40% of root voles and 33.3% of field voles. Congenital B. microti infection was confirmed in 91% of embryos of common voles and in 29% of root voles. B. microti DNA was detected in 70% of pups of common voles and in 83% of root voles. The IRU1 genotype was dominant in wild-caught voles (92%), pregnant females (83%) and dams (60%). The IRU2 genotype was dominant among positive embryos (68%) and pups (71%).Conclusion: high rate of vertical transmission of two genotypes of B. microti was confirmed in naturally infected comm