From the Guidelines
The patient does not need to restart the hepatitis B vaccination series if they missed the second or third dose that was due two months ago, and they should continue the series where they left off by getting the missed dose as soon as possible. The standard hepatitis B vaccine schedule consists of three doses given at 0,1, and 6 months, but there is no maximum interval between doses 1. While delays might postpone full protection, the immune system still "remembers" previous doses, and the series remains effective even with extended intervals.
The immune response to the vaccine is based on immunological memory, so additional doses build upon the initial response regardless of the time elapsed 1. The patient should be advised to complete the remaining dose(s) promptly to achieve full protection against hepatitis B virus infection. After completing the full series, no additional doses or testing are typically needed for healthy individuals, as the vaccine provides long-lasting immunity in most people. It's worth noting that the Advisory Committee on Immunization Practices (ACIP) recommends that if the HepB vaccination schedule is interrupted, the series does not need to be restarted, and the second dose should be administered as soon as possible, with the second and third doses separated by an interval of at least 8 weeks 1.
Some key points to consider when administering the hepatitis B vaccine include:
- The final dose of vaccine must be administered at least 8 weeks after the second dose and should follow the first dose by at least 16 weeks 1
- Inadequate doses of hepatitis B vaccine or doses received after a shorter-than-recommended dosing interval should be readministered, using the correct dosage or schedule 1
- Vaccine doses administered ≤4 days before the minimum interval or age are considered valid 1.
Overall, the patient should continue with the remaining doses of the hepatitis B vaccination series as soon as possible to ensure full protection against the virus.
From the Research
Hepatitis B Vaccination Schedule
- The standard hepatitis B vaccination schedule consists of three doses, typically administered at 0,1, and 6 months 2.
- However, there are also accelerated schedules available, such as a two-dose schedule with a minimum interval of 4 weeks between doses, followed by a third dose at least 4 months after the second dose 3.
Missed Vaccination Doses
- If a patient misses a dose of the hepatitis B vaccine, it is not necessary to restart the entire series 4.
- Instead, the patient should receive the next dose as soon as possible, and the series can be completed according to the recommended schedule.
Implications of Missed Doses
- Missing doses of the hepatitis B vaccine can lead to incomplete protection against the virus, which can increase the risk of infection and its associated morbidity and mortality 5.
- It is essential to complete the vaccination series to ensure optimal protection against hepatitis B virus.
Clinical Guidance
- Clinicians should follow established guidelines for hepatitis B vaccination, screening, and linkage to care to reduce the burden of chronic hepatitis B virus infection 4.
- Patients who have missed doses of the hepatitis B vaccine should be counseled on the importance of completing the series and receiving any additional doses as needed.