Immunity Duration of Hepatitis A Vaccine
The Hepatitis A vaccine, a crucial preventive measure against the viral disease, provides long-lasting protection to individuals who complete the full two-dose series. This vaccine, available in the United States as Havrix and Vaqta, is administered to children as part of their routine vaccinations, starting at 12-23 months old, with the second dose given at 2-4 years old.
The vaccine is made by growing cells of the hepatitis A virus in human fibroblast cells and inactivating the virus with formalin. It is then combined with an aluminum hydroxide adjuvant. Studies have demonstrated that over 97% of vaccinated individuals retain anti-HAV antibodies 20 years after the two-dose vaccination series, indicating long-lasting immunity.
For adults, the vaccine schedule varies slightly. Those receiving Havrix need a second dose 6-12 months after the first, while those receiving Vaqta need a second dose 6-18 months after the first. Protection against the hepatitis A virus (HAV) may last at least 20 years after the full vaccine series, according to the CDC. However, some modeling studies and observed data suggest that immunity could persist even longer than 20 years; yet, routine booster doses are not currently recommended based on available evidence.
Individuals who receive only one dose may have protection lasting around 12 to 18 months but require the second dose for extended protection. Immunize.org suggests that the hepatitis A vaccine might last at least 25 years for adults and about 14-20 years for children.
It is essential to note that people should inform their doctor if they are unwell before receiving the vaccine, as they may need to wait before getting it. Adults with an increased risk of HAV infection may also need the vaccine, including people traveling internationally, males who have sex with males, people who use drugs with or without needles, people at risk of exposure due to their occupation, people who may have close personal contact with an international adoptee, people without housing, people with chronic liver disease or HIV, and pregnant women at risk of HAV infection or severe disease from HAV infection.
The hepatitis A vaccines are highly effective at preventing HAV infection, with completing the full vaccination schedule offering long-term protection against the virus. Side effects of the vaccine are usually mild and temporary, including soreness at the injection site, tiredness, headache, and fever. These side effects typically resolve within a few days.
The hepatitis A vaccine is not suitable for people who have ever had a severe allergic reaction to the vaccine or if they are allergic to any component of the vaccine. If people have not received the hepatitis A vaccination, they need to receive the first dose as soon as they know they will be traveling, and then receive the second dose as per the vaccination schedule.
For further information, individuals can visit the HHS website or consult their healthcare provider. The vaccine may be available at a pharmacy, doctor's office, travel clinic, or health center. In some cases, the vaccine may be free or low cost, or it may be covered by insurance.
In summary, full vaccination (two doses) against hepatitis A confers long-term protection commonly lasting 14 to 20 years or more, supported by antibody persistence studies up to at least 20 years post-vaccination. The hepatitis A vaccine is a crucial tool in preventing the spread of the viral disease and maintaining public health.
- Science has developed vaccines and immunizations, such as the Hepatitis A vaccine, to offer long-lasting protection against viral diseases.
- For adults receiving Havrix, a second dose of the Hepatitis A vaccine is required 6-12 months after the first, while for Vaqta recipients, it's 6-18 months.
- People with medical conditions like chronic kidney disease, COPD, type-2 diabetes, and mental health issues may also require the hepatitis A vaccine due to their increased risk of the virus.
- Therapies and treatments, like nutrition and CBD, might help manage chronic diseases like rheumatoid arthritis, but they are not substitutes for vaccinations like the hepatitis A vaccine.
- Fitness and exercise are essential components of a healthy and well-balanced life, but they do not provide immunity against medical conditions like hepatitis A.
- The hepatitis A vaccine is strongly recommended for individuals traveling internationally, especially to locations where the virus is prevalent, as protection may last at least 14 to 20 years, possibly more.
- It's important to consult healthcare providers or visit the HHS website for guidance on the hepatitis A vaccine, as it may be free or low cost and available at pharmacies, doctors' offices, travel clinics, or health centers.
