Studies on herpes simplex virus. V. The fate of viable herpes simplex virus administered intravenously to man.

Summary A viable egg-adapted strain of herpes simplex virus was injected intravenously in large amounts in 11 human volunteers and attempts were made at various intervals thereafter to recover the virus from the blood by inoculation into fertile eggs. No significant amount of virus could be recovered by any method employed. The small amount of virus which was recovered after inoculation onto the chorioallantoic membrane could not be transmitted by serial passage in ovo . A complement-like heat labile substance was demonstrated in the plasma of one patient which inhibited the propagation of herpes virus in ovo . Neutralization tests performed on sera obtained from the individuals prior to the virus injection demonstrated marked differences in titer of neutralizing antibodies to herpes virus. In contrast to the previous findings that the antibody titer did not change after injection of inactivated herpes virus, the intravenous injection of viable virus resulted in significant rises in neutralizing antibody levels in 4 out of 9 persons. The role of antibody, the heat labile plasma factor and viral removal mechanisms is discussed. Egg-adapted strains of herpes virus failed to exhibit hemagglutination activity when tested in vitro against a wide variety of animal red blood cells, in contrast to the claims of Moolton et al .