Microparasites of three species of shrews from Finnish Lapland

Forty-five common shrews, Sorex araneus, caught in 1997; and 48 S. araneus, 21 masked shrews, Sorex caecutiens, and 25 pygmy shrews Sorex minutus trapped in 1998 at Kilpisjärvi in northern Finland were examined for microparasites. Bartonella sp. was found in blood smears of S. araneus both in 1997 (prevalence 15%) and 1998 (10%) but no blood parasites were found in S. caecutiens or S. minutus. This is the first report of blood parasites of shrews from Finland. A fungal parasite, Pneumocystis carinii, was also observed in S. araneus both in 1997 (prevalence 31%) and in 1998 (58%). In contrast to previous reports, 20% of S. minutus had cyst forms of P. carinii in the lungs but none of the S. caecutiens were infected. Results of this study and related studies from elsewhere indicate that the blood parasite communities of Sorex shrews are less diverse than those found in small rodents. In this study the prevalence of Bartonella was highest in the most abundant host species in the shrew community.