How long does the Hep B vaccination last My 12 year old son had this at birth and his school is now offering this vaccination for the grade 7s. Should he be vaccinated a 2nd time?

The hepatitis vaccine consists of more than one dose. If your child did not receive the second and third in the series of vaccinations, it may be wise to revaccinate. There is no risk in revaccination. If you have your child's vaccination records, I recommend consulting a physician or the school nurse for further advice. Hepatitis B vaccinations are generally thought to last 20 years or more, when delivered correctly.