The Adult Immunization Catch-Up Schedule: A Practical Guide for Primary Care

Who needs catch-up vaccination?

•Immigrants and refugees with incomplete vaccination histories

•Previously uninsured adults now gaining coverage (Medicaid expansion, ACA)

•Adults from vaccine-hesitant families aging into independence

•Adults with lost or unavailable records

•Adults with delayed schedules never completed

•The challenge: CDC publishes catch-up schedules for children and teens, but adult catch-up guidance is scattered across multiple documents and requires clinical synthesis.

•Key principle: Never restart a vaccine series. Resume where you left off, regardless of interval length.

Step 1: Risk stratification

Patient factors: •Age (26, 50, 65 = key thresholds) •Pregnancy planning/ status •Chronic conditions (diabetes, COPD, heart disease) •Immunocompromising conditions •Asplenia/complement deficiency

Exposure risks: •Occupation (healthcare, daycare, lab) •Living situation (congregate, college dorm) •Travel plans (international) •Sexual activity patterns •MSM •injection drug use

💡 Clinical pearl: Don't let perfect documentation be the enemy of protection. Self-report of previous doses is acceptable for most vaccines. When in doubt, vaccinate.

Step 2: Priority tiering for adult catch-up vaccination

Priority 1: Vaccines start here

•MMR (Measles, Mumps, Rubella) •Who: Adults born 1957 or later without evidence of immunity •Dosing: 1-2 doses depending on risk •General population: 1 dose •Healthcare workers, international travelers, college students: 2 doses (4 weeks apart) •Evidence of immunity: Born before 1957, lab confirmation, or documented vaccination

Priority vaccines, continued

•Tdap/Td (Tetanus, Diphtheria, Pertussis) •Unvaccinated adults: 3-dose primary series•Dose 1: Tdap (preferred) •Dose 2: Td or Tdap at least 4 weeks later •Dose 3: Td or Tdap 6-12 months after dose 2 •Then: Td or Tdap every 10 years •Pregnancy: Tdap during weeks 27-36 of each pregnancy

⚠️ Don’t miss: Many "vaccinated" adults never received pertussis as children (DTP was different). All adults should receive at least one Tdap, even if "up to date" on Td.

Priority 2 vaccines: Multidose series

Hepatitis B (3-dose series) •Universal recommendation: All unvaccinated adults through age 59 •Age 60+: Risk-based (diabetes, HCV, sexual risk, healthcare exposure) •Schedule: 0, 1 month, 6 months
(or accelerated 2-dose Heplisav-B at 0, 1 month for age 18+) •Tip: Self-report acceptable; if uncertain vaccination status, just start series

💡 Clinical pearl: If patient received 1 or 2 doses years ago, don't restart. Just complete the remaining doses.

Priority 2: Multidose series

HPV(2-3 dose series) •Catch-up through age 26: Recommended for all •Ages 27-45: Shared decision-making (limited benefit for most) •Schedule: •2-dose: 0, 6-12 months (if starting age 9-14) •3-dose: 0, 1-2 months, 6 months (if starting age 15+ or immunocompromised)

Special situations: No documentation

When there is no documentation: •CDC Guidance: "Administer recommended vaccines if vaccination history is incomplete or unknown. Do not restart or add doses to vaccine series if there are extended intervals between doses." •Translation: When in doubt, vaccinate. Self-report counts. Extra doses of inactivated vaccines are safe.

Special situations: Pregnancy

•Safe to give: Tdap (weeks 27-36 each pregnancy), influenza, COVID-19, RSV (weeks 32-36, Sept-Jan), inactivated vaccines generally •Contraindicated: MMR, varicella (live vaccines) •Wait until after pregnancy: HPV •Key point: If live vaccine given inadvertently during pregnancy, no intervention needed—just counsel and reassure

Special situations: Immunocompromise

•Avoid live vaccines: MMR, varicella (unless carefully assessed) •May need additional doses: Hep B, pneumococcal, COVID-19 •Enhanced schedules available: Refer to Table 2 in CDC schedule

Smart combination vaccine strategies

Vaccine documentation and reimbursement

What to document •Vaccine name, manufacturer, lot number, expiration date •Administration date •Anatomic site and route •Name/title of person
administering •VIS edition date and date given to patient

If documentation is missing: •Best practice: Create an "Adult Immunization Assessment" note documenting: •Patient self-report of vaccination history •Attempts to obtain records (including from which sources) •Risk assessment findings •Plan for catch-up series with rationale

Billing considerations

•Most adult vaccines: Covered by insurance under ACA preventive services (no copay) •Medicare Part D: Covers most vaccines; some covered under Part B •Uninsured: VFC program doesn't cover adults; check state programs, manufacturer assistance •Code separately: Vaccine product code + administration code for each vaccine

Medical Necessity: When giving vaccines outside typical age ranges, document risk factors clearly to support coverage (eg, "Patient with diabetes requires pneumococcal vaccination")

Action steps for primary care practice

•Create a template "Adult Catch-Up Assessment" in your EMR
•Train staff to screen for vaccination status at every visit
•Stock commonly needed vaccines for immediate administration
•Develop patient handouts explaining catch-up process
•Use standing orders to increase vaccination opportunities

Key takeaways for adult catch-up vaccination in primary care

•Never restart a series. Resume where you left off, regardless of time elapsed.

•Self-report is acceptable. When in doubt, vaccinate.

•Prioritize based on disease severity, outbreak potential, and time-sensitive windows (HPV age 26).