PubMed · 7863394
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
R J Hift, A E Simjee. 1994. Hepatitis A.. https://pubmed.ncbi.nlm.nih.gov/7863394/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Explore the source record for details and available documents.
BACKGROUND: The transmission of hepatitis A virus (HAV) has been associated with the use of a number of solvent/detergent-treated factor VIII concentrates and possibly a factor IX concentrate. These reports have emphasized the necessity of using virus-inactivation methods for plasma products that are capable of inactivating nonenveloped viruses such as HAV. STUDY DESIGN AND METHODS: A simple, highly accurate titration procedure for HAV, which allows extensive kinetic investigations of virus-inactivation procedures, has been developed. This system has now been used to evaluate the efficacy of vapor heating in inactivating HAV after the addition of the virus to a range of human plasma products. RESULTS: It was demonstrated that HAV was significantly more thermostable than other picornaviruses, which reinforced the fact that such viruses cannot be used as model viruses for HAV-inactivation studies. A one-step vapor-heating procedure was demonstrated to inactivate between 5.9 and > 6.3 log10 of HAV in different products. A two-step vapor-heating procedure had the capacity to inactivate between > 8.7 and > 10.4 log10 of HAV. Both procedures were more effective in inactivating HAV than was the pasteurization procedure used for virus inactivation in human albumin solutions. CONCLUSION: These data demonstrate the efficacy of vapor heating in inactivating high-titer HAV after the spiking of plasma products with virus. This study confirms and explains the results of controlled clinical trials and long-term clinical usage with respect to the lack of HAV transmission by such vapor-heated products.
Hepatitis A vaccines (Havrix and Vaqta), administered in two doses, provide long-term protection. Target groups include international travelers, children in high-risk communities, homosexually active men, injecting drug users, persons who work with nonhuman primates, patients with chronic hepatitis, and recipients of clotting factors. The place of hepatitis A vaccination in the childhood-immunization schedule has not been determined. Postexposure prophylaxis for hepatitis A consists of administration of immune globulin within 2 weeks of exposure. Hepatitis B vaccines (Recombivax HB and Engerix-B), administered in three doses, provide protective antibody levels in more than 95% of recipients. Duration of protection appears to approach 10 years. Booster doses are not currently recommended. Hepatitis B vaccination has been incorporated into the routine childhood-immunization schedule. Additional target groups include medical personnel exposed to blood products, household and sexual contacts of infected persons, injecting drug users, and homosexually active men. Postexposure prophylaxis consists of administration of hepatitis B immune globulin as soon after exposure as possible, along with the initial dose of vaccine if desired.