Viral replication in the livers of animals following intrahepatic inoculation. C57BL/6 weanling mice were infected intrahepatically with 5,000 PFU of wild-type MHV-A59 (■), wtR10 (•), or wtR1 (▴) (collectively designated wt) (A) C12 (B), 159R36 (C), or 159R40 (D). Animals were sacrificed at the indicated times, and virus titers in the livers were determined by plaque assay. The limit of detection was 500 PFU/g of tissue. The data shown represent the averages (and standard deviations) of the titers from four (wtR10 and wtR1) or six (A59, C12, R36, and R40) animals.