Are there any circumstances when a fifth dose of polio vaccine is recommended?
Yes. If upon record review you find that a dose was given before the minimum age of 6 weeks or if any doses were given before the minimum interval of 4 weeks, then you may need to repeat an invalid dose. Also, if all 4 doses are given before 4 years of age and school law requires a dose after age four, you may have to give a 5th dose. Finally, adults who completed their series as children and are traveling to a polio endemic area may receive a single lifetime booster dose of IPV.
