Polio Vaccination for Adults: ACIP's 2023 Recommendation

This page describes a recommendation adopted by the Advisory Committee on Immunization Practices in June 2023. Check current CDC schedules before acting on it.

Poliovirus can cause poliomyelitis and lifelong paralysis. Wild poliovirus types 2 and 3 have been eradicated, but wild type 1 and vaccine-derived polioviruses still circulate in several countries.

Background

Paralytic polio fell rapidly in the United States after the Salk inactivated poliovirus vaccine (IPV) arrived in 1955 and the Sabin oral vaccine (OPV) in 1961. Trivalent OPV, given routinely to children from the 1960s, eliminated wild poliovirus and community transmission in the United States in 1979. An enhanced-potency IPV was introduced in 1996, and since 1999 IPV has been the only polio vaccine recommended for routine use.

Until 2023, ACIP recommended polio vaccination for adults 18 and older only if they were at increased risk of exposure.

What changed: New York, 2022

In 2022, a paralytic polio case caused by circulating vaccine-derived poliovirus type 2 was identified in an unvaccinated young adult in New York. Wastewater testing then found genetically linked virus in six New York counties during April–October 2022 — community circulation — and sequencing tied it to virus found in wastewater in Canada, Israel and the United Kingdom. This was only the second known instance of community poliovirus transmission in the United States since 1979.

Rockland County, where the case was found, has had low childhood vaccination for more than 20 years: in summer 2022 only 60% of children under 2 had their 3 IPV doses, and in some zip codes as few as 37%, against 93.4% nationally for children born in 2018–2019. The episode showed that unvaccinated and incompletely vaccinated adults live in the United States, often clustered in communities with low childhood vaccination, and that poliovirus can be imported as long as it circulates anywhere.

The evidence

• Effectiveness: 3 IPV doses at least 2 months apart, starting at 2 months or older, produce protective antibodies in at least 95% of recipients a month after the third dose; antibodies correlate with protection against paralysis. Unlike OPV, IPV doesn't prevent gut infection or shedding, but it appears to reduce shedding from the nose and throat.
• Safety: over more than 20 years of use, IPV's safety has been highly favorable. Injection-site tenderness is the most common reaction (14%–29% in trials); giving IPV with other vaccines hasn't increased side effects, and no serious adverse events have been causally linked to it.
• Boosters: a 2009–2010 national survey found at least 79% of adults 20–49 had antibodies to all three types, showing antibodies last for decades. A booster raises the share with antibodies to 98%–100%.

The recommendations

Unvaccinated or incompletely vaccinated adults. On June 21, 2023, ACIP recommended that adults 18 and older who are known or suspected to be unvaccinated or incompletely vaccinated against polio complete a primary series with IPV.

Vaccinated adults at increased risk. Adults who completed a primary series of trivalent OPV or IPV in any combination and are at increased risk of exposure may receive one lifetime IPV booster — unchanged from before. Increased risk includes:

• travel to countries where polio is epidemic or endemic;
• laboratory and health care work with specimens that may contain poliovirus;
• close contact, as health care workers or caregivers, with patients in a community with a polio outbreak;
• membership in a group that public health authorities identify as at increased risk because of an outbreak.

Clinical guidance

• Assume childhood vaccination unless there's reason to doubt it: polio vaccine has been part of routine childhood immunization since the late 1950s, so most adults raised in the United States were vaccinated even without records.
• A complete primary series is at least 3 properly spaced doses of trivalent OPV or IPV, the last on or after the fourth birthday. (That age rule dates from August 2009; people who received 4 or more doses before then count as fully vaccinated regardless.)
• Adult schedule: 2 IPV doses 4–8 weeks apart, then a third 6–12 months after the second; there's no need to restart if intervals run long. If protection is needed sooner, as before travel: with more than 8 weeks, 3 doses at least 4 weeks apart; with 4–8 weeks, 2 doses at least 4 weeks apart; with under 4 weeks, one dose — completing the rest later.
• Weakened immunity: IPV is safe for immunocompromised people and their contacts but may work less well during immunosuppression, so give it — including any expected booster — beforehand when possible.
• Contraindication: a severe allergic reaction to IPV or to the trace antibiotics it contains (streptomycin, polymyxin B or neomycin).
• Pregnancy is a precaution: there's no evidence of harm, but IPV shouldn't be given in pregnancy unless the person is at increased risk and needs immediate protection.

Report any adverse event after vaccination to the Vaccine Adverse Event Reporting System (VAERS), online or at 1-800-822-7967.

Sources

• Kidd S, Clark T, Routh J, Cineas S, Bahta L, Brooks O. "Use of Inactivated Polio Vaccine Among U.S. Adults: Updated Recommendations of the Advisory Committee on Immunization Practices — United States, 2023." Morbidity and Mortality Weekly Report 72(49), Centers for Disease Control and Prevention.