Lymphocytic Choriomeningitis Virus

Prepared by: Michael J. Huerkamp, DVM, Diplomate ACLAM
Date: December 19, 2005

Agent: Lymphocytic Choriomeningitis Virus

Laboratory-associated infections with LCM virus are well-documented in facilities where infections are present in laboratory rodents – especially mice, hamsters and guinea pigs. Nude, SCID, immunologically abnormal and congenitally-infected mice pose a special risk of harboring inapparent, chronic infections. Infected cell cultures and transplantable tumors are additional sources of dissemination and infection.

Potential Hazard: The virus may be present in blood, cerebrospinal fluid, urine, other body fluids, feces and tissues of infected animals. Transmission may occur by inoculation; by contamination of mucous membranes of the eyes, nose and mouth; by exposure of broken skin, across the placenta, and by AEROSOL transmission. Clinical signs of infections in people may vary greatly, but infection usually appears as a mild influenza-like illness, with or withoutinvolvement of the central nervous system. Some people may become severely ill, requiring hospitalization. Congenital infections are possible. The virus may pose a SPECIAL RISK during PREGNANCY because of potential infection of the fetus.

Recommended Precautions:

  • Laboratory-adapted, mouse brain-passaged strains in rats or mice infected as adults: The animal biosafety level II+ practices (DAR SOP 400-3) will protect husbandry personnel against exposure or infection. Fully immunocompetent rodents with these attenuated infections typically clear the infection within one week.
  • Virulent strains and/or congenital infection of mice, infection of hamsters and guinea pigs, infection of nude, SCID or immunologically altered mice: The animal biosafety level III practices (DAR SOP 400-14) will protect husbandry personnel against exposure or infection. These rodents may have persistent, silent infections and shed a large amount of virus.
  • Vaccines are not available for use in humans.

References:Amer J Pathol 151: 633-9, 1997.
Barton LL. Mets MB. Beauchamp CL. Lymphocytic choriomeningitis virus: emerging fetal teratogen. American Journal of Obstetrics & Gynecology. 187(6):1715-6, 2002.
Biosafety in Microbiological and Biomedical Laboratories, 4th edition, CDC-NIH, 1999, pp. 163-64, 190.
Enders G. Varho-Gobel M. Lohler J. Terletskaia-Ladwig E. Eggers M. Congenital lymphocytic choriomeningitis virus infection: an underdiagnosed disease. Pediatric Infectious Disease Journal. 18(7):652-5, 1999.