The older generation, there may be many people who have not been vaccinated against hepatitis B, do not know much about it, and even think that it is not good that I have not been vaccinated. Is hepatitis B vaccine really useful?
Today, Dr. Clove will tell you whether hepatitis B vaccine is useful or not.
Hepatitis B vaccine is very useful
China is a big country with hepatitis B, and there are about 90 million people infected with chronic HBV in China. This figure also means that the positive rate of hepatitis B surface antigen in the general population in China is 7.18%.
According to the 2014 National Epidemiological Survey of Hepatitis B, hepatitis B surface antigen (HBsAg) is positive, which is what we usually call the infection rate of hepatitis B virus, which is 0.32%, 0.94% and 4.38% respectively in the population aged 1-4 years old, 5-14 years old and 15-29 years old.
Can these data show what?
These data mean that the younger the population in our country, the lower the infection rate of hepatitis B.
A large part of the credit is due to the large-scale hepatitis B immunization in the past few decades.
According to a report by the World Health Organization in 2016, hepatitis B vaccination has greatly reduced the proportion of children and adolescents suffering from hepatitis B typhoid by 97%.
Who needs a vaccine?
1. Newborns
Newborns within 28 days of birth are the most in need of protection. They are the most important targets for hepatitis B vaccination. Whether their mothers carry hepatitis B virus or not, they need vaccination.
2. Infants and young children, non-immunized population under 15 years old
Children’s ability to protect against hepatitis B invasion is also relatively weak, so vaccination is also needed.
3. High-risk groups
These high-risk groups, including those who may be exposed to a large amount of hepatitis B virus:
- Medical personnel; People who are in regular contact with blood; Nursery staff; Organ transplant recipients, who often receive blood transfusion or blood products; People with low immune function; Family members of hepatitis B positive patients; People with multiple sexual partners and intravenous drug users, etc.
Who doesn’t need a vaccine?
1. People who have been infected with hepatitis B virus.
They don’t need to get hepatitis B vaccine. There are two situations here:
- Hepatitis B virus carrying status: hepatitis B surface antigen positive, HBsAg + hidden infection: hepatitis B core antibody or e antigen positive, HBcAb + or HBeAg +
These two groups of people cannot obtain protection effect through vaccination, so they do not need to be vaccinated again.
2. People with positive surface antibodies.
Surface antibody positive people, HBsAb +, are not mentioned in the above-mentioned [people who need vaccination] and are also people who do not need vaccination because they have sufficient resistance.
How do you judge whether the vaccine is effective?
We take vaccines to obtain protection. How should we judge the effect of vaccines?
1. Is the vaccine effective
The standard vaccination of hepatitis B vaccine shall be carried out in accordance with the procedures of 0, 1 and 6 months, and the quantitative examination of hepatitis B three systems shall be reviewed about 1-2 months after the vaccination is completed, and the concentration of hepatitis B surface antibody (HBsAb) shall be judged. Generally, there are three situations:
Effective
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It is generally believed that HBsAb greater than 100 mIU/mL is a sufficient immune response to provide long-term protection.
Low answer that may not be valid
- BsAb is between 10 mIU/mL and 100 mIU/mL. It is true that the antibody titer of some vaccinators is low or even undetectable. At this time, the specific methods for boosting immunization to promote antibody production are not uniform. The author’s attitude is that if the antibody titer after vaccination is low, one dose of vaccine can be added. If there is no response, it can be reexamined 1-2 months after 3 injections are completely inoculated again. If there is still no response, it can be double-metered inoculation with 1 injection.
Repeated inoculation has no effect.
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In medicine, this is called [no response], HBsAb is less than 10 mIU/mL. For adults, you don’t have to mind this matter. From the perspective of infectivity and harm, the threat of hepatitis B virus to adults is actually very limited.
2. Duration of protection effect
Generally speaking, after the antibody response is generated, the protective effect of the antibody can last for at least 12 years.
Because the effect is lasting, HBsAb monitoring or revaccination is not needed to strengthen immunization.
This is due to the fact that the memory B cells that produce antibodies are very long-lived cells and have good [memory]. Once the memory B cells are exposed to the stimulation of hepatitis B virus again, they can quickly proliferate a large number of B cells to quickly synthesize effective antibodies.
Moreover, there is no high-risk behavior in the general population, but if they are exposed to a small amount of virus, the less antibody amount in the body is enough to cope with it.
3. Some people should pay special attention to
For the high-risk groups mentioned earlier in the article, when HBsAb is found to be negative, hepatitis B vaccine needs to be vaccinated again.
Because there is the possibility of one-time contact with a large amount of hepatitis B virus, if the antibody amount is not enough to resist the virus, causing the virus to enter liver cells from the blood, there is also the risk of being breached and infected.
In addition to the economy and obvious effect of hepatitis B vaccine itself, it is suggested that when HBsAb is found to be negative in high-risk groups, hepatitis B vaccine should be vaccinated again to ensure sufficient protective antibodies in blood.
High-risk groups that cannot be positive after repeated vaccination also belong to the above-mentioned [low response] and should be treated according to the method.
There are also unique ways to deal with infection.
Hepatitis B vaccine is a good thing with low cost and extremely high efficiency, but there are still some situations that cannot be well protected. For example:
- People with low response and no response have had contact (called exposure) that may be infected with hepatitis B.. Newborns whose mothers carry hepatitis B virus.
Under these circumstances, what should I do?
Don’t worry, we still have unique skills. Hepatitis B immunoglobulin can play the role of [leak detection and vacancy filling]. As long as we follow the doctor’s arrangement, we can effectively prevent hepatitis B virus infection.