Theiloviruses (TMEV, RTV)
RNA virus, nonenveloped.
Common in laboratory colonies, and wild rats and mice.
Serology or PCR.
Disease in mice can result from the rare occurrence of viraemia, which occurs most frequently around 6 – 10 weeks of age. In most cases, natural infection with theiloviruses is asymptomatic.
Several strains have been identified.
Regular serological testing is recommended.
TMEV and RTV are shed through the faecal – oral route.
In the case of TMEV, animals are persistently infected and virus is shed for approximately two months after infection.
Environment should be chemically decontaminated with the help of detergents and oxidising agents. Materials in contact with animals should be autoclaved or cold sterilised.
Rare as a natural infection of contemporary mice and rats. TMEV can interfere with research on the nervous system, immune system and musculoskeletal system. Little is currently known about the effects of RTV on research in rats and consequently an infection should be treated with caution.
Culling and replacing infected animals. Hysterectomy rederivation and embryo transfer.
Infectious Diseases of Mice and Rats. National Research Council 1991.
Charles River Laboratories website, www.criver.com