A SEROLOGIC SURVEY FOR VIRUSES AND MYCOPLASMA-PULMONIS AMONG WILD HOUSE MICE (MUS-DOMESTICUS) IN SOUTHEASTERN AUSTRALIA

Plasma samples from 267 wild house mice (Mus domesticus) trapped at 14 sites in southeastern Australia were screened for antibody to 14 viru ses normally associated with laboratory-reared rodents and to Mycoplas ma pulmonis. Serologic prevalence was high for murine cytomegalovirus (99%, n = 94), murine coronavirus (95%), and murine rotavirus (74%). S amples from mice collected at all sites contained antibody to these vi ruses. The serologic prevalence was lower for mouse adenovirus, strain K87 (37%), parvovirus (33%), and reovirus type 3 (28%), with substant ial site-to-site variation. Plasma from mice collected at 12 sites con tained mouse adenovirus or reovirus antibody, and samples from mice at eight sites contained parvovirus antibody. Parvovirus-antibody positi ve mice were typically from high density populations or from low densi ty populations that had recently declined from high density. Antibody to lymphocytic choriomeningitis virus (LCMV) and Sendai virus occurred at only three sites, and the serologic prevalence was very low (9.6% and 1.8%, respectively). All of the LCMV-positive mice were from north eastern New South Wales. The presence of this zoonotic virus in a mous e plague-prone region raises questions about human health risks result ing from cohabitation with large numbers of mice. It appeared that mou se populations at high density or declining from high density had high er prevalence of viral antibody than populations that had been at low or moderate density for some time. Thus, viral epizootics may occur am ong high-density populations and may be responsible for or precipitate declines in mouse density. These data raise the possibility of rodent viruses having potential as biological control agents.