Studies on Serum and Infectious Hepatitis Viruses of Man

A preliminary report of the results so far describe briefly the recovery of the serum hepatitis virus from five human volunteers who acquired serum hepatitis after inoculation with prototype B SH virus and from one patient acutely ill with (presumably transfusion caused) serum hepatitis, as well as the recovery of IH virus from two patients acutely ill with infectious hepatitis. In all instances the SH and IH viruses have been passaged six to 13 times in stable lung cell tissue culture with a different but characteristic cytopathologic effect for the SH and IH viruses. Titration of the SH viruses showed that the TCID50, per ml. ranged from 10‐4.5 to 10‐6.0 per ml. and the IH from 10‐5.5 to 10‐6.6. Neutralizing antibodies against two SH viruses were produced in rabbits and against one IH virus in the guinea pig. A definite serological relationship has been established by neutralization tests between the virus from one of the SH volunteers and the virus from the patient with SH; between the two IH viruses; and between the SH and the IH viruses. The identity of the SH virus isolate from one of the volunteers was demonstrated by the production of neutralizing antibodies in a rabbit inoculated with NIH plasma pool #6, although attempts to grow virus from the plasma pool failed. The SH viruses are not inactivated by heating at 60 C. for four to six hours, the IH viruses are. SH virus killed mice and was recovered in tissue culture from their livers. IH virus did not infect mice. Both viruses have been grown also in trypsinized rabbit, guinea pig and hamster kidney tissue cultures and in human embryonic tissue cultures. Neither virus will grow in monkey kidney, ruling out most other enteric and adenoviruses of human origin. Further reports will be made as the studies continue.