IMMUNIZATION FOR VIRAL-HEPATITIS

Viral hepatitis is among the most common infections worldwide. Previou sly, in the absence of specific therapy, management was confined to pr evention by improving standards of health and hygiene in underdevelope d countries or by provoking passive immunization using immune globulin either prophylactically or within hours of infection. in the 1980s, f irst plasma-derived, then recombinant hepatitis B vaccines were introd uced. In 1991 an inactivated hepatitis A vaccine was licensed in Europ e. This latter vaccine has recently been approved by the Food and Drug Administration for use in the United States. Hepatitis C, because of its heterogeneity and tendency to escape immune pressure by forming qu asispecies, has thus far eluded attempts at developing an effective va ccine. Nevertheless, intense research continues in pursuit of both vac cine development and improved vaccination strategies for ail types of viral hepatitis.