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Research has been conducted on maternal HIV-1 genotype in MT-2 cells. The association of this genotype at or near delivery time with perinatal HIV-1 transmission has been investigated and the results demonstrate that the association of the nonsyncytium-inducing phenotype with transmission is stronger in women who has received azidothymidine during pregnancy.

The ELISA test for hepatitis C virus appears to be more accurate in HIV-infected patients than in patients who are not infected with HIV. This probably occurs because HIV-infected patients are less likely to clear the hepatitis C infection than an HIV-negative person.

In 1974, it was first recognized that not all cases of viral hepatitis were hepatitis A or hepatitis B. It proved difficult to identify the infectious agent responsible for these cases of non-A, non-B hepatitis. However, it has recently become clear that many cases of post-transfusion non-A, non-B hepatitis are the result of infection with a new virus, hepatitis C. Modern immunological and genetic engineering techniques have resulted in tests that can detect antibody to hepatitis C virus (HCV). A major study has now been conducted to compare the first HCV antibody tests with more recently developed tests, and to determine the fraction of transfusion recipients with non-A, non-B hepatitis due to infection with hepatitis C. The study was conducted on 1,247 transfusion recipients and 1,235 matched controls. A total of 115 transfusion recipients developed non-A, non-B hepatitis; HCV antibodies were already present in four patients prior to the bout of hepatitis. Of the remaining 111, 46 percent developed antibodies, as indicated by the first generation tests. When the new antibody test was used, a total of 60 percent were found to have HCV antibodies. Forty of the control patients developed hepatitis from causes unrelated to transfusion during the study period. Of these, three already had antibodies to HCV. In contrast, however, none of the remaining 37 patients developed HCV antibodies after developing hepatitis. This suggests that the rate of non-A, non-B hepatitis is about three percent in those who have not received transfusions. Assuming the same rate holds for the 1,247 transfusion recipients, then 37 of the 111 cases of non-A, non-B hepatitis would likely have happened anyway. The remaining 74 cases may be attributable to the transfusion, and since 67 of these cases were positive by the second-generation antibody test, 91 percent of post-transfusion hepatitis cases clearly involve hepatitis C infection. The study also found that not all the donor blood that transmitted HCV was positive by the antibody test. However, many specimens had elevated alanine aminotransferase; increases in this liver enzyme strongly hint at the presence of subclinical hepatitis. Testing donor blood for both HCV and alanine aminotransferase could greatly reduce the transmission of hepatitis C to transfusion recipients. (Consumer Summary produced by Reliance Medical Information, Inc.)

The vaccine that is currently used against hepatitis B infections is effective, but its use is limited because of its high cost. This study investigated the feasibility of substituting an intradermal (injected under the skin rather than into muscle) vaccine containing lower dosages of the surface antigen, hepatitis B surface antigen, (HBsAg). (Antigen stimulates the production of specific antibodies; in this case an immunized individual would have antibodies against hepatitis B.) Medical students are one of the groups at increased risk for contracting the hepatitis B virus (HBV) and were used as the subjects of this study. Ninety-two healthy young students volunteered for the study and were screened for previous exposure to the virus. The subjects were given a low-dose intradermal injection of Heptavax-B, containing the active ingredient HBsAg, which was followed up with additional injections at one month and at six months. Measurement of HBsAg antibody levels were also taken at these intervals and again after one year had elapsed. Some minor abnormalities were observed in the tissue area surrounding the injection site. At the six-month interval, 18 percent of the students had a hardening of the tissue at the injection site, but this disappeared by the end of one year. Another side effect which persisted in 63 percent of the subjects for over a year was a discoloration of the skin. Tests made at six months indicated levels of antibodies at greater than or equal to 10mlU per ml for HBsAG. At the end of one year 95 percent of the subjects showed antibody levels greater than or equal to 10mlU per ml and 75 percent actually had levels exceeding 100mlU per ml. It was concluded that Heptavax-B is a safe and economic means of providing immunization to large groups of people. The authors believe that the value of this technique is significant because universal vaccination is being considered for children in this country and Heptavax-B may provide the best method.