Consensus and Misunderstanding of Hepatitis B (Part I)

China is called a “big country with hepatitis B”. Almost one in ten Chinese people has hepatitis B carriers. The health damage and social and economic burden caused by chronic hepatitis, liver cirrhosis and liver cancer caused by hepatitis B every year are amazing. No infectious disease in our country is more harmful than hepatitis B. In the case of no effective prescription to completely cure hepatitis B in clinical practice, it is particularly important to prevent hepatitis B infection.

Since the 1980s, China has tried to vaccinate some areas with human blood-derived hepatitis B vaccine. However, human blood-derived hepatitis B vaccine comes from hepatitis B carriers, There are major shortcomings of insufficient yield and potential pathogenicity. In the early 1990s, Merck Company transferred its beer yeast hepatitis B vaccine production line to China at a symbolic price of 1 yuan money. China has thus solved the problem of the production and safety of hepatitis B vaccine. In the late 1990s, Beer yeast hepatitis B vaccine has completely replaced human blood-derived hepatitis B vaccine. After entering the 21st century, New breakthroughs have been made in the production process of hepatitis B vaccine. At present, beer yeast and Hansenula hepatitis B vaccine occupy the mainstream in China’s hepatitis B vaccine market, and another hepatitis B vaccine cultured from Chinese hamster ovary cells is also used to some extent, commonly known as CHO hepatitis B vaccine.

From the 1980s to 2010, China has been using hepatitis B vaccine for nearly 30 years. There have been relatively thorough studies on different technologies of hepatitis B vaccine, different doses of hepatitis B vaccine, different vaccination procedures, vaccination effects of different populations, mechanisms of immune failure and re-immunization.

As the preventive effect of hepatitis B vaccine is very significant, China’s hepatitis B control and control,The key is to choose the appropriate vaccination strategy.

Consensus ①: Hepatitis B is an infectious disease transmitted by body fluids. Its transmission route is the same as AIDS. Many countries classify hepatitis B as a sexually transmitted disease. Due to the huge base of hepatitis B carriers in China, mother-to-child transmission of hepatitis B is the main problem, so hepatitis B is not classified as a sexually transmitted disease.

Myth: Because you often eat out, you are required to be vaccinated against hepatitis B.

Mistake: After contacting with hepatitis B carriers, they worry about getting hepatitis B, which causes psychological problems.

Mistake explanation: In fact, the possibility of common contact infection is very small. As an adult, even if he is infected, he has more than 90% assurance that he can heal himself. In order to prevent hepatitis B vaccine, it is possible, but there is no need to worry too much.

Consensus 3: There are two mechanisms for the immunity of hepatitis B vaccine. One is humoral immunity, i.e. Antibodies that can be usually detected. The other is cellular immunity, which is usually undetectable. Current research has confirmed that even if antibodies cannot be detected, most people can still be immune to hepatitis B virus. In other words, negative antibodies do not mean no immunity. At present, it is generally accepted that hepatitis B vaccine does not need to be vaccinated again.

Myth: After being vaccinated with hepatitis B vaccine, if the antibody turns negative, it is required to be vaccinated again, even once every 3-5 years.

Mistake explanation: Can’t measure the presence or absence of hepatitis B immunity with negative or positive antibody. Consensus 4: Most mother-to-child transmission of hepatitis B can be blocked through vaccination, but there are still about 5% of newborns infected with hepatitis B in uterus, which is a difficult problem that cannot be solved by current medicine.

Myth: Vaccinate the mother of hepatitis B carriers with hepatitis B immunoglobulin, which can neutralize the hepatitis B virus in the mother’s body and help reduce the risk of mother-to-child transmission.

Interpretation of Mistakes: In theory, hepatitis B immunoglobulin can neutralize hepatitis B virus, However, it must be considered whether the dose is sufficient. If the amount of hepatitis B virus in the body is 100, the conventional dosage of hepatitis B immunoglobulin can only neutralize 1-2 of the hepatitis B virus, which cannot reduce the risk of mother-to-child transmission. It is very unreliable to reduce the risk of hepatitis B transmission by inoculating mothers with hepatitis B immunoglobulin.

Consensus ⑤: There are very few people who cannot develop immunity even if they are repeatedly vaccinated with hepatitis B vaccine. These people can still be infected with hepatitis B, At ordinary times, attention should be paid to avoid high-risk behaviors. Mistake After being vaccinated with hepatitis B vaccine for many times, no antibody can be detected, It is required to continue the vaccination until the antibody is detected. Mistake explanation: It is generally believed that after 3 doses of hepatitis B vaccine have been vaccinated according to the standard procedure, there is no antibody, and 3 doses can be vaccinated according to the standard procedure (if the first time is low dose, the second time is recommended to use high dose). If there is still no antibody, there is no need to vaccinate again.