看到这个帖子时就想查查关于乙肝病毒传染途径的资料，直到现在才有空做这件事。贴一些资料上来，希望对楼主有用。

[ 本帖最后由 陌上桑 于 2010-1-18 22:51 编辑 ].

以下资料来自美国疾控中心CDC
http://www.cdc.gov/hepatitis/HBV/HBVfaq.htm#treatment

How is HBV transmitted?

HBV is transmitted through activities that involve percutaneous (i.e., puncture through the skin) or mucosal contact with infectious blood or body fluids (e.g., semen, saliva), including

    * Sex with an infected partner
    * Injection drug use that involves sharing needles, syringes, or drug-preparation equipment
    * Birth to an infected mother
    * Contact with blood or open sores of an infected person
    * Needle sticks or sharp instrument exposures
    * Sharing items such as razors or toothbrushes with an infected person

HBV is not spread through food or water, sharing eating utensils, breastfeeding, hugging, kissing, hand holding, coughing, or sneezing..

从上述资料中得到的信息时，唾液中可以含有乙肝病毒，但HBV并不通过食物、水、公用食具、握手、亲吻、咳嗽、喷嚏等传播。
不过请注意，美国的日常饮食都是分餐制。.

http://jama.ama-assn.org/cgi/reprint/278/24/2167

这个案例报道一位小学老师被携带乙肝病毒的学生传染而引发急性肝炎。确定该学生是感染源的原因是两者的病毒亚型和DNA序列一致。老师反映，在某次意外中他（她）皲裂的手接触过孩子的唾液和鼻涕。这篇文章中还提到唾液中的病毒滴度（即浓度）比血液中的低几个数量级。

[ 本帖最后由 陌上桑 于 2010-1-18 23:13 编辑 ].

以下资料同样来自美国疾控中心CDC
http://www.cdc.gov/hepatitis/HBV/HBVfaq.htm#treatment
How long does protection from Hepatitis B vaccine last?

Studies indicate that immunologic memory remains intact for at least 20 years among healthy vaccinated individuals who initiated Hepatitis B vaccination >6 months of age. The vaccine confers long-term protection against clinical illness and chronic Hepatitis B virus infection. Cellular immunity appears to persist even though antibody levels might become low or decline below detectable levels.

Among vaccinated cohorts who initiated Hepatitis B vaccination at birth, long-term follow-up studies are ongoing to determine the duration of vaccine-induced immunity..

半岁以后才开始接种疫苗的，免疫力可持续至少二十年。
出生时就接种疫苗的，免疫力可持续的时间还不清楚，相关的研究还在进行中。

[ 本帖最后由 陌上桑 于 2010-1-18 23:06 编辑 ].