Is the polio vaccine for adults in the United States administered by injection or orally?

Polio Vaccine Administration in U.S. Adults

In the United States, polio vaccine for adults is administered by injection (intramuscularly or subcutaneously), not orally. The only polio vaccine currently distributed in the U.S. is inactivated poliovirus vaccine (IPV), which is given as an injection. 1

Current U.S. Vaccine Formulation

• IPOL® is the only IPV product both licensed and distributed in the United States, administered as a 0.5 mL injection either subcutaneously or intramuscularly. 1

• The injection is given in the deltoid area for adults, using standard sterile technique. 2

• IPV contains inactivated (killed) poliovirus and cannot cause vaccine-associated paralytic poliomyelitis, unlike oral poliovirus vaccine (OPV). 3, 4

Why Not Oral Vaccine?

• Oral poliovirus vaccine (OPV) is no longer used for routine vaccination in the United States as of 2000, though an emergency stockpile exists for outbreak control only. 1, 5

• OPV was discontinued for routine use because it carried a risk of vaccine-associated paralytic poliomyelitis (VAPP) of approximately 1 case per 750,000 first doses distributed. 6, 5

• The switch to all-IPV eliminated 8-10 cases of VAPP annually in the U.S. 7

Adult Vaccination Indications

• Routine poliovirus vaccination is not necessary for most U.S. adults who were vaccinated as children, as they retain immunity and domestic exposure risk is minimal. 1, 8

• IPV is recommended for unvaccinated adults at increased risk, including:

  • Travelers to polio-endemic or epidemic regions 1, 8
  • Laboratory workers handling poliovirus specimens 1, 8
  • Healthcare workers with close contact to patients potentially excreting wild poliovirus 1, 8
  • Members of communities with active wild poliovirus circulation 1, 8

• Following the 2022 New York case of vaccine-derived polio in an unvaccinated adult, ACIP now recommends that all U.S. adults known or suspected to be unvaccinated or incompletely vaccinated should complete a primary IPV series. 3

Adult Dosing Schedule

• Standard primary series for unvaccinated adults: 3 doses of 0.5 mL IPV

  • Dose 1: Initial
  • Dose 2: 4-8 weeks (minimum 4 weeks) after Dose 1
  • Dose 3: 6-12 months after Dose 2 1, 8, 2

• Accelerated schedules when rapid protection is needed:

  • If >8 weeks available: 3 doses at least 4 weeks apart 1, 8
  • If 4-8 weeks available: 2 doses at least 4 weeks apart 1, 8
  • If <4 weeks available: Single dose (complete remaining doses later if risk persists) 1, 8

• Previously vaccinated adults at increased risk: One lifetime booster dose of IPV is sufficient; no additional boosters are needed. 1, 8

Safety and Contraindications

• IPV is extremely well tolerated with no serious adverse events documented in routine use. 1, 8

• Contraindications include:

  • History of anaphylaxis to a previous IPV dose 1, 8
  • Known hypersensitivity to streptomycin, polymyxin B, or neomycin (trace components) 1

• IPV can be administered simultaneously with other vaccines without compromising safety or immunogenicity. 1, 2

Common Pitfalls

• Do not confuse single-antigen IPV (IPOL®) with pediatric combination vaccines (e.g., Kinrix®, Pediarix®), which are inappropriate for adult primary vaccination. 8

• Never administer IPV intravenously—only intramuscular or subcutaneous routes are appropriate. 2

• Adults without documentation of vaccination status should be considered unvaccinated and offered the complete primary series if they fall into high-risk categories. 1, 8