VIRO-IMMUNOLOGY LABORATORY ANIMAL DISEASES DEPARTMENT Of BIOLOGICAL SCIENCES UNIVERSITY OF QUEBEC AT MONTREAL RESEARCH REPORT APRIL 2002 CONTROL OF RISK TRANSMISSION OF HEPATITIS VIRUS IN A MURINE

Animal model : To study the possibility of a viral transmission through the use of the air pressure injector, we have chosen the mouse hepatitis viral infection as a mouse model since this virus is highly infectious and induces a fulminant hepatitis leading to a rapid death in selected mouse strains. The serotype 3 of MHV strain is the most virulent strain of this virus and induces hepatitis in 48hrs in C57BL/6 mice, the most susceptible mouse strain. The death is caused by a fulminant hepatitis and occurs within three days after infection. The viremia occurs after 48 hrs postinfection (p.i.). The MHV infection in mice is use as an animal model of human viral hepatitis since, the virus also induces a chronic hepatitis in some other mouse strains, such as C3H or SJL and F1(C57BL/6xA\J) mice. The chronic hepatitis follows the survival of the mice to the acute phase of the disease. Hepatocytes are the most target cells to viral replication in the hepatitis process. However, blood cells can also be infected and support an efficient viral replication. The MHV3 infects macrophages, monocytes and B lymphocytes. .An interesting point of this viral infection is the fact that the also induces a rapid immunodeficiency due to the viral replication in dendritic cells, macrophages and lymphocytes, increasing thus the gravity of the hepatitis. The inoculation site has no effect on the outcome of the disease. The hepatitis can be induced following intraperitoneal, cutaneous, intramuscular, intraveinous and also, intracranial injection. By natural ways, an intranasal or oral administration of the virus induces the hepatitis in C57BL/6 mice.