Viral hepatitides have long been important public health problems in humans. The etiologic agents were not identified, until around 1965 when Baruch S. Blumberg first found the relationship of Australia antigen and serum hepatitis. Further characterizations revealed the antigen to be the surface antigen of the hepatitis B virus. This epoch-making observation launched a new era in the diagnosis, prevention and treatment of hepatitis B. In about 15-20 years, the natural history of hepatitis B virus infection was elucidated, and more importantly, an effective vaccine against the infection became available. In the meantime, the routes of transmission were also made clear, rendering interruption of the transmission more specific and effective. The hepatitis B vaccine together with the effective means of interrupting the transmission routes contributed greatly to the control of hepatitis B virus infection. However, these measures can do very little to those who have already been chronically infected. Fortunately, specific therapies against chronic hepatitis B have started to appear about 10-15 years before and the treatments improved substantially in the last few years. Although far from perfect, now we do have some effective means to treat those who are chronically infected.

In Taiwan, acute and chronic liver diseases have been known to be rampant in as early as the beginning of the last century. Studies around 1975 showed an extreme high prevalence of chronic hepatitis B infection in the general population (15%-20%), and 80%-90% of the chronic liver diseases as well as hepatocellular carcinoma were caused by chronic infection with the hepatitis B virus. This important health problem, repeatedly addressed by the academia in Taiwan, finally caught the attention of the Government in the late 1970s, and a government-sponsored control program was finalized in 1981. Accordingly, a mass vaccination program against hepatitis B, primarily aiming at immunizing newborn infants, was launched on July 1, 1984. Twenty years after implementation of the program, the hepatitis B carrier rate in children covered by the program decreased 85%, from ~15% to <1%. Most importantly, the deadly sequela of hepatocellular carcinoma in the vaccinees was also found to decrease in parallel . This is the first time in history that a human cancer is prevented by vaccination. Despite the success, there are still some who were born after implementation of the program but were not prevented from chronic hepatitis B infection and hepatocellular carcinoma. Non-compliance to vaccination schedule, breakthrough infection and intrauterine infection are the causes of the failure.

At present, we have effective measures in immunizing the susceptibles, interrupting the routes of transmission and treating the chronically infected people. The time of considering elimination or even eradication of hepatitis B virus infection has come. This is especially true for countries where hepatitis B infection is not endemic. Nevertheless, with the admirable results achieved in the past, Taiwan should also start to think about elimination/eradication of hepatitis B in the country, even though it will certainly be much more difficult than in the non-endemic countries.

Dr Suzanne Wait has spent substantial efforts and time in exploring the possibility of eliminating/eradicating hepatitis B in Taiwan. She reviewed the epidemiology of hepatitis B, and analyzed the problems that remain to be tackled in Taiwan. With this essay as an important reference, I hope that Taiwan can take further steps towards the elimination or eradication of hepatitis B.