Abstract: Objective To establish reovirus type 3 ( Reo-3) infection model of ICR mice and observe clinical syndrome, investigate virus load in target organs and serology dynamic change in infected mice. Method Animal adaption method was used to increase the virus’s virulence. Systemic infection model was established with tail vein and intraperitoneally inoculation to ICR. The clinical sign was observed. The tissues and serums were harvested on 0 d before and 4 d、7 d、18 d、25 d、35 d、72 d、129 d after inoculation. Blood samples of three mice were randomly collected on 47 d、81 d、103 d. qPCR and ELISA were respectively used to detect the virus nucleic acid at target tissue and the antibody level. Results Virus virulence was increased after four times adaption trial. Mice death was observed at d7, d9, d10, d11, d16 post inoculation. The highest load of the virus was found in liver through qPCR, followed by heart, spleen, and lung. The peaks of viral load emerged from 6 to 11 d in all organs, negative results appeared at 129 d in the most organs. The earliest antibody detect time was on 18 d. The titer of antibody hit the peak on 25 d, then maintained a high level till to 129 d. Conclusion virus virulence can be enhanced significantly through mouse in-vivo inoculation, multiple organs inflammation and early death in mice can be identified by the systemic infection way of Reo-3. This experiment provides an approach to establish Reo-3 infected mice animal model and provides good experimental data for further research on Reo-3 infection mechanism .

Key words: Reovirus type 3(Reo-3), Infection, Clinical research, Respiratory intestinal disease