The 2020 CDC guidance for hepatitis A vaccination: All unvaccinated persons aged 1–18 years should receive 2 doses of hepatitis A vaccine (minimum interval: 6 months). Patients who previously received 1 dose at age 12 months or older should receive dose 2 at least 6 months after dose 1. All appropriate adults 19 years or older should receive a 2-dose hepatitis A vaccination series (minimum interval: 6 months).