Hepatitis B(HB) virus(HBV) infection, which causes liver cirrhosis and hepatocellular carcinoma, is endemic worldwide. Hepatitis B vaccines became commercially available in the 1980 s. The World Health Organization re...Hepatitis B(HB) virus(HBV) infection, which causes liver cirrhosis and hepatocellular carcinoma, is endemic worldwide. Hepatitis B vaccines became commercially available in the 1980 s. The World Health Organization recommended the integration of the HB vaccine into the national immunisation programs in all countries. HBV prevention strategies are classified into three groups:(1) universal vaccination alone;(2) universal vaccination with screening of pregnant women plus HB immune globulin(HBIG) at birth; and(3) selective vaccination with screening of pregnant women plus HBIG at birth. Most low-income countries have adopted universal vaccine programs without screening of pregnant women. However, HB vaccines are not widely used in low-income countries. The Global Alliance for Vaccine and Immunization was launched in 2000, and by 2012, the global coverage of a three-dose HB vaccine had increased to 79%. The next challenges are to further increase the coverage rate, close the gap between recommendations and routine practices, approach highrisk individuals, screen and treat chronically infected individuals, and prevent breakthrough infections. To eradicate HBV infections, strenuous efforts are required to overcome socioeconomic barriers to the HB vaccine; this task is expected to take several decades to complete.展开更多
Hepatitis B virus(HBV) infection is still a serious worldwide problem, and vaccination is the most effective strategy for primary prevention of the infection. Although universal vaccination may be required for total e...Hepatitis B virus(HBV) infection is still a serious worldwide problem, and vaccination is the most effective strategy for primary prevention of the infection. Although universal vaccination may be required for total eradication, several countries, including Japan, have not yet adopted universal vaccination programs. Some individuals are non-responders to HBV vaccine and several mechanisms responsible for their poor response have been proposed. To overcome non-response, third generation vaccines with pre-S proteins have been developed. These vaccines have shown better antiHBs responses and may also be effective in preventing infection by HBV with S mutant. Improvement of vaccine efficacy by intradermal administration, or coadministration with cytokines or adjuvants, may also be effective in non-responders. The necessity, timing and method of booster vaccination in responders with decreased anti-HBs responses, and effective vaccination against S-mutant HBV, are issues requiring resolution in the global prevention of HBV infection.展开更多
文摘Hepatitis B(HB) virus(HBV) infection, which causes liver cirrhosis and hepatocellular carcinoma, is endemic worldwide. Hepatitis B vaccines became commercially available in the 1980 s. The World Health Organization recommended the integration of the HB vaccine into the national immunisation programs in all countries. HBV prevention strategies are classified into three groups:(1) universal vaccination alone;(2) universal vaccination with screening of pregnant women plus HB immune globulin(HBIG) at birth; and(3) selective vaccination with screening of pregnant women plus HBIG at birth. Most low-income countries have adopted universal vaccine programs without screening of pregnant women. However, HB vaccines are not widely used in low-income countries. The Global Alliance for Vaccine and Immunization was launched in 2000, and by 2012, the global coverage of a three-dose HB vaccine had increased to 79%. The next challenges are to further increase the coverage rate, close the gap between recommendations and routine practices, approach highrisk individuals, screen and treat chronically infected individuals, and prevent breakthrough infections. To eradicate HBV infections, strenuous efforts are required to overcome socioeconomic barriers to the HB vaccine; this task is expected to take several decades to complete.
文摘Hepatitis B virus(HBV) infection is still a serious worldwide problem, and vaccination is the most effective strategy for primary prevention of the infection. Although universal vaccination may be required for total eradication, several countries, including Japan, have not yet adopted universal vaccination programs. Some individuals are non-responders to HBV vaccine and several mechanisms responsible for their poor response have been proposed. To overcome non-response, third generation vaccines with pre-S proteins have been developed. These vaccines have shown better antiHBs responses and may also be effective in preventing infection by HBV with S mutant. Improvement of vaccine efficacy by intradermal administration, or coadministration with cytokines or adjuvants, may also be effective in non-responders. The necessity, timing and method of booster vaccination in responders with decreased anti-HBs responses, and effective vaccination against S-mutant HBV, are issues requiring resolution in the global prevention of HBV infection.