A pool of whole-mouth saliva collected from five human carriers of hepatitis B surface antigen, subtype adr, was found to contain antigen particles with mean diameters of 23.3 and 41.8 nm as seen by immune electron microscopy. Two gibbons received subcutaneous injections of the pooled saliva and developed serological and, in at least one animal, biochemical evidence of hepatitis B virus infection at 12 and 22 weeks, respectively. Although none of eight other gibbons that were exposed by the nasal or oral routes were infected, the experiment demonstrated that human saliva can serve as a vehicle for the transmission of hepatitis B virus.

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An antimalarial drug testing system is described which utilizes trophozoite induced Plasmodium cynomolgi malaria in rhesus monkeys. The schizonticidal activity of standard antimalarial drugs in this system is reported. The system accurately predicted antimalarial activity in man of 8 of 9 compounds selected for clinical trials.

No abstract