Fall 1996 Volume 1, Number 3		Top hepatitis abstracts from the ICACC Here are the top public health abstracts on viral hepatitis from the 36th Interscience Conference on Antimicrobial Agents and Chemotherapy, held in New Orleans September 15-18: Hepatitis A A group from Ben Gurion University in Israel, headed by R. Dagan, evaluated the immunogenicity of a combination hepatitis A + B vaccine versus separate hepatitis A and hepatitis B vaccinations (both manufactured by Merck). Preliminary results showed anti-HBs and anti-HA responses in the combination vaccine group that were similar to the separate-vaccines group. T.L. Cromeans and colleagues from CDC described a new hepatitis A antibody test that could be used to distinguish infection from vaccination. The test, evaluated in chimps and humans, detected nonstructural 3C protein, which is produced only during viral replication and not by vaccination. M. Hoyt and others from CDC evaluated adverse events (AEs) after vaccination with inactivated hepatitis A vaccine (VAQTA, Merck and Co.) among about 12,000 children immunized in 1995 in Butte County, California during an outbreak (see HCR April 1996). As of March 1996, no serious side effects were reported. Of a smaller group actively followed to assess mild AEs, 4.4% of subjects reported fever greater than or equal to102 degrees F after the first dose, and 5.1% reported fever after the second dose. Ninety-eight percent of all AEs were pain and tenderness at the site of injection. G. De Serres and co-workers from Centre de Sant Publique de Quebec, Canada, described three waste water treatment plant workers who contracted hepatitis A during a communitywide outbreak. The authors concluded that hepatitis A can be a "professional disease" for such workers, because the cases had no special risk factors for hepatitis A infection and were "not linked to the outbreak." However, the authors also noted no correlation between anti-HAV seroprevalence and levels of exposure to sewage fluids in a small seroprevalence study done at the sewage plant. Hepatitis B Z. Nadel and CDC colleagues studied whether antibody response to influenza vaccine predicts response to hepatitis B vaccine. The non-response rate to influenza vaccine was 24% among hepatitis B responders and 33% among non-responders, indicating no significant difference. Chronic diseases such as heart or lung disease predicted non-response to both vaccines. A therapeutic hepatitis B vaccine may be feasible, according to investigators from SmithKline Beecham in Belgium led by M. Wettendorf. They described experiments with several hepatitis B vaccine and immunostimulant combinations in HBsAg transgenic mice, an animal model for human HBsAg carriers. One formulation, containing alum and immunostimulants, did appear to stimulate anti-HBs antibody and suppress HBsAg production successfully, leading the investigators to conclude that "breaking of tolerance can be achieved with hepatitis B vaccine formulated with potent immunostimulants." Hepatitis E A.G. Barriga and colleagues from Hospital de Infectologia in Mexico City reported on a serosurvey of 233 persons in Veracruz State and Mexico City for antibody to hepatitis E virus (EIA HEV IgG). The total seroprevalence was 2.5%. In rural towns the seroprevalence was 6.3%. In urban areas it was 0.6%. Two hepatitis E outbreaks had been reported in Mexico previously.