The Hepatitis A vaccine is an immunization against a viral disease that causes liver inflammation. It is very safe, but some children develop mild fevers or seizures. Serious side effects are very rare.
The vaccine is an immunization against Hepatitis A, which is a liver infection that is caused by a virus that spreads in feces. Health officials recommend vaccination against Hepatitis A for all children in the United States when they are 1 year old and people in high-risk groups.
The Hepatitis A vaccine is administered by an injection into the muscle of the upper arm for adults and older children. It is injected into the thigh muscle of toddlers and younger children.
Two. You will need two shots of the Hepatitis A vaccine, with the second dose given at least 6 months after the first dose.
The original Hepatitis A vaccine was only for people at high risk of Hepatitis A and it could not be given to children under 2 years old. In 2005, a new vaccine was approved that could be given to young children. In 2006, the United States began recommending that infants between 12 months and 23 months receive the Hepatitis A vaccine.
The Hepatitis A vaccine is made by taking the virus that causes Hepatitis A and killing it with the chemical formaldehyde. This inactivates the virus so it can’t cause Hepatitis A. The vaccine may contain very low levels of formaldehyde.
All children starting at age 1 year (12-23 months) should get the hepatitis A vaccine. Children who are not vaccinated by the time they are 2 years old should be vaccinated as soon as possible.
Get vaccinated against Hepatitis A if you:
- Want to avoid Hepatitis A infections
- Might have been exposed to the Hepatitis A virus in the last two weeks
- Travel or work in countries with high rates of Hepatitis A (everywhere except Australia, New Zealand, Northern and Western Europe, Japan, and Canada)
- Have contact with an adopted child within 60 days of the child’s arrival from a country where Hepatitis A is common
- Have chronic liver disease
- Have a blood clotting-factor disorder (for example, hemophilia)
- Are a man who has sex with men
- Use street drugs
The vaccine does not protect you from Hepatitis A right away. It takes about 2 weeks to start working, and 4 weeks to reach maximum effectiveness.
Experts estimate that the Hepatitis A vaccine could last for 25 years in adults and 14-20 years in children who are fully immunized with two doses of the vaccine.
Two doses of the Hepatitis A vaccine are given to children. The first dose is given between the ages of 12 months and 23 months. The second dose is given 6-18 months later.
Two doses of the Hepatitis A vaccine are given at least 6 months apart.
Yes. The new version of the Hepatitis A vaccine that was introduced in the United States in 1995 is very safe.
To learn more about the side effects associated with Hepatitis A vaccines (Havrix & Vaqta), please visit this page: Hepatitis A vaccine side effects.
The Hepatitis A vaccine can cause pain, redness, and tenderness where the shot was injected. It causes headaches in about 5 out of every 100 recipients. Some children develop mild fevers. Allergic reactions are extremely rare.
There have been a few reports of people who had severe side effects, but it is unknown if these side effects were actually caused by the vaccine. The potential risks include:
- Birth defects
- Guillain-Barré Syndrome (GBS)
- Erythema multiforme
- Multiple sclerosis
- Nerve damage
- Non-viral hepatitis (liver inflammation)
- Serum sickness-like syndrome
No. The vaccine used in the United States contains a virus that is inactivated (dead) and it can’t cause Hepatitis A.
However, outside the U.S., there are some Hepatitis A vaccines that contain live attenuated viruses (based on H2 or LA-1 HAV strains). These vaccines are used mostly in China and sometimes in India.