The occurrence of Cryptosporidium parvum and C-muris in wild rodents and insectivores in Spain

Five rodent and two insectivore species were investigated for Cryptosporidi um at seven sites in north-eastern Spain. Of the 442 animals studied, 82 Ap odemus sylvaticus, 1 A. flavicollis, 5 Mus spretus, 1 Rattus rattus, 8 Clet hrionomys glareolus and 13 Crocidura russula were infected with only C. par vum. Eleven A. sylvaticus and 2 C. glareolus were infected with only C. mur is and 16 A. sylvaticus, 1 M. spretus and 2 C. glareolus showed mixed infec tions. Both cryptosporidial species were found in most study areas. No caus al relationship was found between intrinsic host factors (age and sex) and the parasitic prevalence in the most captured host species (A. sylvaticus a nd C. russula). Extrinsic factors such as collection site of host, seasonal ity and covering vegetation exerted different influence on the prevalence o f Cryptosporidium. Small mammals could become one of the most important sou rces of cryptosporidial oocysts in those areas where neither farm animals n or significant human activity are present. This is the first study to repor t the infection of M. spretus and C. russula by C. parvum and the first fin ding of C. muris in M. spretus. (C) 2000 Elsevier Science B.V. All rights r eserved.