How long does the hepatitis A vaccine last?

The hepatitis A vaccine is injected when we are born, mainly to prevent diseases such as hepatitis A and hepatitis B. These vaccines can be effective for more than 20 years, and hepatitis A is mainly transmitted through congenital infection. Nowadays, many people do not pay attention to liver care and are prone to hepatitis A. For hepatitis A vaccine, we should choose one with better quality, and it needs to be sterilized before being injected into the human body.

The validity period of the hepatitis A vaccine

Currently, there are two types of hepatitis A vaccines: inactivated hepatitis A vaccine and live attenuated vaccine (live vaccine includes water injection and freeze-dried preparation). The ingredients of inactivated vaccines are whole virus particles that are purified after inactivation, while the ingredients of live attenuated vaccines are mainly attenuated live viruses. The live attenuated vaccine injection is inexpensive and the hepatitis A vaccine is effective for more than 5 years, but it has the weakness of poor vaccine stability. Freeze-dried live attenuated vaccines that overcome this weakness have become available in recent years. The inactivated vaccine has a high antibody titer and the effectiveness of the hepatitis A vaccine can last for more than 20 years. Since the virus is fully inactivated, there is no risk of virulence recovery and safety is fully guaranteed. Inactivated vaccines are used abroad.

Best time to get hepatitis A vaccine

The inactivated hepatitis A vaccine is one of the vaccines recommended by the World Health Organization. Children under one year old have weaker resistance to the virus, so it is best to get the hepatitis A vaccine. About 8 weeks after receiving the hepatitis A vaccine, high levels of antibodies can be produced, giving you good immunity. Therefore, hepatitis A vaccine has good immune protection.

The specific time for hepatitis A vaccination is:

1. Initial immunization time: for those who are susceptible to hepatitis A and are over one year old;

2. Immunization can be boosted six months after the initial immunization;

3. Those who have received live hepatitis A vaccine in the past can receive booster vaccination regardless of the length of the interval. Effective period: In recent years, observations on population vaccination have shown that if the hepatitis A live attenuated vaccine is used for immunization with the "two-injection method", with an interval of 1 month, 3 months, 6 months or 12 months, the anti-HAV positivity rate can reach 100%, and the anti-HAV titer can reach more than 1000 MIU/ml. It is recommended that the hepatitis A live attenuated vaccine be administered twice to provide lifelong immunity.