What to do if the Human Papillomavirus (HPV) vaccine schedule is interrupted?

Management of Interrupted HPV Vaccination Schedule

If the HPV vaccine schedule is interrupted, the vaccine series does not need to be restarted. Simply administer the missed dose(s) as soon as possible, maintaining minimum interval requirements between doses. 1, 2, 3

General Principles for Interrupted HPV Vaccination

• If the series is interrupted after the first dose, administer the second dose as soon as possible, ensuring the second and third doses are separated by at least 12 weeks 1
• If only the third dose is delayed, administer it as soon as possible without restarting the series 1
• The minimum interval between the first and second doses is 4 weeks 1
• The minimum interval between the second and third doses is 12 weeks 1

Age-Specific Considerations

• For individuals who initiated vaccination before age 15:

  • A 2-dose schedule is recommended with doses at 0 and 6-12 months 2, 3, 4
  • If the second dose is delayed, administer it as soon as possible 3

• For individuals who initiated vaccination at age 15 or older:

  • A 3-dose schedule is recommended with doses at 0,1-2, and 6 months 2, 3, 4
  • If any dose is delayed, administer it as soon as possible while maintaining minimum intervals 1

Special Considerations

• Inadequate doses (e.g., doses given after shorter-than-recommended intervals) should be readministered 1
• Longer intervals between doses do not diminish vaccine effectiveness and may actually enhance immune response 5
• Individuals with certain immunocompromising conditions require a 3-dose schedule regardless of age at initiation 3

Clinical Pearls

• HPV vaccination can be administered at the same visit as other age-appropriate vaccines using separate syringes at different anatomic sites 1, 2
• Vaccination is most effective when given before exposure to HPV through sexual activity, but sexually active individuals should still complete their vaccination series 3, 6
• Cervical cancer screening recommendations remain unchanged for vaccinated individuals 1

Common Pitfalls to Avoid

• Don't restart the entire vaccine series if doses are delayed - this wastes resources and unnecessarily exposes patients to additional doses 1, 2
• Don't assume that longer intervals between doses reduce effectiveness - evidence suggests delayed dosing may actually result in similar or higher antibody titers 5
• Don't forget that the minimum intervals between doses must still be maintained when catching up on missed doses 1