Infection of the Severe Fever with Thrombocytopenia Syndrome Virus in Balb/C Mice and Hamsters / 病毒学报

ABSTRACT

The severe fever with thrombocytopenia syndrome virus (SFTSV) is the causative pathogen of an emerging infectious disease severe fever with thrombocytopenia syndrome and a new member in the genus Phlebovirus of family Bunyaviridae. Immune responses and pathological lesions in SFTSV-infected Balb/C mice and hamsters were evaluated by inoculation of SFTSV at 105 TCID50 or 103 TCID50 per animal through four different routes of infection, including intravenous, intramuscular, intraperitoneal, and intracerebral injections. The vehicle control groups were also included. At different time points after the inoculation blood and plasma samples were collected. Blood cell counts, blood viral RNA copies, and plasma antibodies were detected by automatic blood cell counters, real-time PCR, and luminex assays, respectively. At two weeks post inoculation, the animals were sacrificed. Tissues including heart, liver, spleen, lung, kidney, intestine, muscle, and brain, were collected for pathological analyses. Results showed that the SFTSV could infect Balb/C mice and hamsters with SFTSV-specific immunoglobulin (Ig) M and IgG antibodies detected in plasma samples on day 7 post inoculation. The SFTSV-specific IgM levels peaked on day 7 post inoculation and then decreased, whereas the SFTSV-specific IgG levels started to increase on day 7 and then peaked on day 14 post inoculation. Pathological analyses indicated significant pathological lesions in liver and kidney tissues. In conclusion, SFTSV could can infect different strains of rodent animals and cause similar immunological and pathological responses.