Effect of urea and uric acid on influenza virus type C. Brief report.

The replication of influenza type C/1233 virus following inoculation into the amniotic sac of embryonated hen's eggs is significantly greater than that seen in the allantoic cavity. However, optimal growth condition for amniotically propagated C/1233 occur in the allantois of 8-day old embryos incubated post-inoculation at 32 degrees C. Differences in pH levels between the amniotic and allantoic cavities did not account for the variable growth ability of C/1233 virus, but in both in vitro and in ovo studies, levels of urea and uric acid, or urea-uric acid mixtures caused significant reductions in virus yield.