Clinical experience with therapeutic vaccines designed for patients with hepatitis.

Franciscan missionary Giovanni Di Plano Carpini traveled in 1245 to a country named Yeke Tartar, to visit a certain man called Genghis Khan. His journey's report narrated peculiar dietary habits of the locals: "they eat anything, even lice". Little that Carpini knew, he had actually documented the earliest known to us record of oral vaccination against blood-borne infections - an approach that is still used occasionally in the present-day Mongolia for therapy of hepatitis. Currently, efforts aimed at developing therapeutic hepatitis vaccines have switched to more palatable path, but we may still benefit from the insight of medieval Mongols. This review provides an update on development of hepatitis B and C vaccines as related to immunotherapy of hepatitis. Immune therapy is a fast-moving field but the results so far failed to pitch woo. Current trends in research on therapeutic vaccine candidates and liver immunology are discussed. We subscribe to the idea that viral hepatitis is essentially an autoimmune disease generating immune-mediated liver damage. Therapeutic vaccines need to be designed in such a way that self-destructive immunity of the host is targeted not the virus, which is not cytopathic.

Seroepidemiology of hepatitis B virus infection among children in Mongolia: results of a nationwide survey.

BACKGROUND: Because Mongolia is one of the highly endemic countries for hepatitis B virus (HBV) infection in the world, hepatitis B (HB) vaccine was introduced into the National Expanded Program on Immunization in 1991. However, relatively few data are available concerning HBV infection among children born after the start of the program, so far. The aim of the present paper was to describe the seroepidemiology of HBV infection among primary school children using representative national data. METHODS: In 2004, a nationwide school-based cross-sectional serosurvey was carried out throughout Mongolia, covering both urban and rural areas. Serum samples were tested for hepatitis B surface antigen (HBsAg), antibody to hepatitis B core antigen (anti-HBc) and hepatitis B e antigen (HBeAg) as well as for liver enzymes. RESULTS: A total of 1145 children aged 7-12 years were studied, which represents nearly 2% of the second grade population of elementary schools in Mongolia. The overall prevalence of HBsAg and anti-HBc was 5.2% (95% confidence interval [CI]: 3.9-6.5%) and 15.6% (95%CI: 13.5-17.7%), respectively. Among HBsAg-positive children 67.8% (95%CI: 55.9-79.7%) were also positive for HBeAg. The prevalence of chronic HBV infection increased by age and was significantly higher among children from rural areas compared to those from urban areas (7.7% vs 3.0%; P < 0.001). In the multivariate logistic regression analysis, rural residence (odds ratio [OR]: 2.57; 95%CI: 1.45-4.58), male sex (OR: 1.9; 95%CI: 1.08-3.26) and age (OR: 1.5; 95%CI: 1.10-2.05) were independent demographic predictors for chronic HBV infection. CONCLUSIONS: The prevalence of chronic HBV infection has been decreasing in the Mongolian young generation, most likely due to infant HB vaccination. However, significant rural-urban differences in the prevalence of HBV infection were found that demand further investigation to estimate the potential causes.