抄録
Taiwan has adopted the vaccination system against hepatitis B virus for all infants since 1984, while many countries including Japan have the system of vaccination just for a high-risk group of infants. In this study, we evaluated the system of Taiwan with investigating on young people who were born after 1984 and now get to 16 years old at the eldest. In Tai-tung located in east Taiwan, we first collected blood from 1,300 young people selected at random from residents. Compared with people who were born in 1981-83 and not received anti-hepatitis B vaccine, people who were born in 1984-91 and more than 80% of whom received the vaccine showed a significant lower positive ratio of HBsAg both in male and female. The ratio was also significantly lower compared with the reported data of people who were 10-14 years old in 1983. Since hepatitis B causes hepatic cell carcinoma (HCC) and liver cirrhosis (LC), we analysed the death rate of HCC and LC published by the governments in Taiwan and Japan. The comparisons in a death rate between people who were born in 1975-83 (not received vaccine) and people born in 1984-94 (over 80% received vaccine) revealed that Taiwan system of vaccination significantly reduced the death rate of HCC in male aged 5-10 years old. However, the system did not reduce the death rate in male at over 10 years old, nor in female. On the other hand, the Japanese system of vaccination against hepatitis B virus for a high risk group of infants did not change the death rate either in male nor female. Additionally, the system of Taiwan and Japan tended to reduce the death rate of LC but not significantly. We conclude that 1) the vaccination system of Taiwan contributes to the prevention of hepatitis B in male and female young people. 2) It partly prevented the death of HCC. Since the effects were limited in male aged 5-10 years old, the system may have to be improved in Taiwan. 3) Although the contribution of Japanese system may be less than Taiwan system as regards the prevention of the death of HCC, we could not judge whether Japan should adopt the Taiwanese system from the present data. However, further investigations on the results of the Taiwanese system may help to improve the Japanese system of the prevention of hepatitis B.
