A comparison of the effects of oral inoculation with Rotashield and pentavalent reassortant rotavirus vaccine (WC3-PV) on suckling CB17_scid mice

The effects of oral inoculation into infant CB17_scid mice of two reassortant rotavirus vaccines were compared. The vaccines were Rotashield and WC3-PV, a mixture of five reassortants (G1, G2, G3, G4 and P1; pentavalent reassortant vaccine). Control mice were inoculated with a placebo. At 6 days post-inoculation (p.i.), 8 of 13 (62%; P<0.005) Rotashield-inoculated mice developed hepatitis and/or bile-duct obstruction compared with none of 11 mice given WC3-PV and none of 14 given placebo. In the Rotashield-inoculated mice, only serotype G3 rhesus rotavirus (RRV) was isolated from multiple sites, including intestine, liver, pancreas, spleen, blood and mesenteric lymph nodes. Recovery of RRV from Rotashield-inoculated mice followed a biphasic pattern. The two peaks of RRV recovery appeared to coincide firstly with replication in the intestine during days 1-3 p.i., and secondly with virus infection of the liver from days 10 to 15 p.i. WC3 reassortants of four different serotypes were detected only at day 1 p.i. in the intestine, liver, pancreas and blood cells from three WC3-PV-inoculated mouse pups. However, WC3-PV did not produce any hepatopathology. Rotashield and WC3-PV appeared to exhibit different biological activity in infant CB17_scid mouse pups.