Infectious Disease Survey of Mus musculus from Pet Stores in New York City

Most mice used in research are purchased devoid of specific pathogens. Experimental studies required us to evaluate the profile of infective agents harbored in mice sold as pets or food for captive reptiles. Anecdotal reports regarding disease in these mice abound, but there are few published reports on disease prevalence. Purchasers are unaware of the potential zoonotic or adventitious infections carried by these mice. This survey investigated the prevalence of ectoparasites, endoparasites, and viral, bacterial, and fungal agents carried by apparently healthy mice (n = 18) obtained from 6 pet stores in New York City, with an emphasis on those pathogens with zoonotic potential. Serology revealed the presence of antibodies to numerous murine specific viral agents in most mice tested. Ectoparasites were present on most mice. Examination of intestinal contents revealed nematode and cestode parasites, including a potential cause of human cestodiasis, Rodentolepis nana. A multidrug-resistant β-hemolytic Enterococcus faecium was isolated from the skin of mice from a single pet store; this organism causes community-acquired infections in humans. This study confirms that pet-store mice are exposed to or carry numerous pathogens that are excluded from laboratory rodent colonies. The potential for laboratory animal personnel to serve as mechanical vectors of unwanted infective agents likely is increased when these persons handle pet-store mice at home.