疫苗接种运动加倍乙肝病毒基因突变

StephenW

Vaccination campaign doubles HBV mutations

A universal infant vaccination campaign in China has led the Hepatitis B virus (HBV) to more than double its rate of “breakout” mutations. These mutations may enable the virus to elude the vaccine, necessitating new vaccination strategies. Researchers at the Chinese Centers for Disease Control and Prevention and University of North Carolina, Chapel Hill, report their findings in an article published ahead of print in the Journal of Virology.

Until a universal vaccination program for infants was implemented in 1992, nearly ten percent of Chinese—children included—were infected with HBV. The vaccination campaign has protected an estimated 80 million children, dramatically reducing the percentage of children under 5 who are infected, from nearly 10 percent in 1992 to less than one percent in 2005. But these gains are in danger of being eroded as the virus develops surface mutations.

Taking advantage of 1992 and 2005 survey, investigators found that the prevalence of HBV escape mutants in children rose from 6.5 percent in 1992, before the start of the universal vaccination program, to nearly 15 percent in 2005. Among the control group of adults unaffected by the universal vaccination campaign, the rate of break-out mutants was virtually unchanged.

Hepatitis B is an infectious illness of the liver which can cause vomiting, inflammation, jaundice, and, rarely, death. About a third of the world’s population has been infected at some point in their lives. Transmission of hepatitis B virus results from exposure to infectious blood or bodily fluids containing blood. The infection is preventable by vaccination, which has been routinely used since the 1980s.

Researcher Tao Bian of Chapel Hill says that the vaccine remains quite effective, but that because escape mutants are likely to increase, public health officials need to track the rise of escape mutants, in order to know when it becomes time to consider new vaccination strategies. Measures that might be taken include boosting doses, adjusting the timing of vaccinations, or improving the vaccine. A next generation HBV vaccine has been invented, containing a second antigen in addition to the virus’ surface antigen. That means that both antigens would have to develop breakout mutations in order to elude the vaccine.

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A copy of the manuscript can be found online at http://bit.ly/asmtip0913e.

The Journal of Virology is a publication of the American Society for Microbiology (ASM). The ASM is the largest single life science society, composed of over 39,000 scientists and health professionals. ASM’s mission is to advance the microbiological sciences as a vehicle for understanding life processes and to apply and communicate this knowledge for the improvement of health and environmental and economic well-being worldwide.

StephenW

在中国通用婴幼儿疫苗接种运动已导致乙型肝炎病毒（HBV）一倍以上的速度“突破”的突变。这些突变可能使病毒逃避疫苗，因此需要新的疫苗接种策略。研究人员在中国疾病控制中心和预防和北卡罗莱纳大学教堂山分校，为报告他们的发现在病毒学杂志提前出版印刷的文章。

直到婴儿的通用疫苗接种计划于1992年实施，包括 - 被近百分之十的中国 - 儿童感染乙肝病毒。该疫苗接种运动保护的估计有80万儿童，大幅降低5岁以下儿童中谁被感染，从近10％ ，1992年至不到百分之一，2005年的百分比。但这些收益都在被蚕食，因为病毒的发展面突变的危险。

以1992年和2005年的调查优势，调查发现，乙肝病毒逃避突变在儿童的患病率从6.5 ％增加到1992年的普遍接种程序开始前，近15％在2005年。在成年人中不受普遍接种运动的对照组，可分隔的突变率大致维持不变。

乙型肝炎是一种可引起呕吐，炎症，黄疸，及很少，死亡的肝脏的感染性疾病。大约有三分之一的世界人口已经感染在他们的生活中。传输的从暴露于传染性血液或含血液体液乙型肝炎病毒的效果。这种感染是可以预防通过接种疫苗，其中自20世纪80年代被经常使用。

教堂山研究员陶逼埯说，疫苗仍然相当有效，但由于逃避突变可能增加，公共卫生官员需要追踪逃逸突变体的崛起，为了知道什么时候变成时间考虑新的疫苗接种策略。可能采取的措施包括促进剂，调节免疫接种的时间，或提高疫苗。甲下一代乙肝疫苗已被发明的，含有除病毒的表面抗原的第二抗原。这意味着，两种抗原就必须突破发展的突变，以逃避疫苗。

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手稿的副本可在网上http://bit.ly/asmtip0913e找到。

病毒学杂志是出版的美国微生物学会（ ASM ）的。在ASM是最大的单一生命科学学会，超过39,000科学家和医疗专业人员组成。 ASM的使命是促进微生物科学作为理解生命过程的车辆，并运用和交流这方面的知识对健康和环境和经济福祉全世界的改善。