Prevention

The most effective way to prevent polio is vaccination.

Polio vaccine

Most children in the United States receive four doses of inactivated poliovirus vaccine (IPV) at the following ages:

• Two months
• Four months
• Between 6 and 18 months
• Between ages 4 and 6 when children are just entering school

IPV is safe for people with weakened immune systems, although it's not certain just how protective the vaccine is in cases of severe immune deficiency. Common side effects are pain and redness at the injection site.

Allergic reaction to the vaccine

IPV can cause an allergic reaction in some people. Because the vaccine contains trace amounts of the antibiotics streptomycin, polymyxin B and neomycin, it shouldn't be given to anyone who's reacted to these medications.

Signs and symptoms of an allergic reaction usually occur within minutes to a few hours after the shot. Watch for:

• Difficulty breathing
• Weakness
• Hoarseness or wheezing
• Rapid heart rate
• Hives
• Dizziness

If you or your child has an allergic reaction after any shot, get medical help immediately.

Adult vaccination

In the U.S., adults aren't routinely vaccinated against polio because most are already immune, and the chances of contracting polio are minimal. However, certain adults at high risk of polio who have had a primary vaccination series with either IPV or the oral polio vaccine (OPV) should receive a single booster shot of IPV.

A single booster dose of IPV lasts a lifetime. Adults at risk include those who are traveling to parts of the world where polio still occurs or those who care for people who have polio.

If you're unvaccinated or your vaccination status is undocumented, get a series of primary polio vaccination shots — two doses of IPV at four- to eight-week intervals and a third dose six to 12 months after the second dose.