Could Polio Make a Comeback?

A young adult in New York recently contracted polio, the first case of the virus in the U.S. in decades. The virus was found through wastewater testing in three New York counties, indicating that it could be circulating undetected. This potentially deadly, and sometimes debilitating, viral illness was nearly eliminated with the national vaccination push in the 1950s, but should you be worried about a comeback?

In the 40s and 50s, parents feared polio and its often life-altering outcomes like paralysis. But a safe, effective polio vaccine series has now been a routine part of childhood immunizations for many years. Children in the U.S. usually get the inactivated poliovirus vaccine (IPV) at 2 months, 4 months, 6-18 months and 4-6 years.

In the New York case, the unvaccinated patient lived in a county where only 60% of children had received three doses by the age of 2. The good news is that Louisiana’s polio immunization rates are the second highest in the country at 98%, above the national average of 93%, according to the CDC’s data on incoming kindergartners in 2020.

In addition to the shot, there is an oral polio vaccine (OPV) that contains a weakened live poliovirus. OPVs haven’t been used in the U.S. for over 20 years, but they are still routinely used in other countries. In poorly immunized populations, they can occasionally lead to vaccine-derived polio, the strain that was identified in the New York patient. With such high IPV coverage in the U.S., though, it’s unlikely that vaccine-derived polio would become widespread.

Though the patient had not traveled overseas, public health officials believe the patient contracted the vaccine-derived strain from a person who had received the OPV and then spread it. Polio is spread through contact with the feces of an infected person, or less commonly, through droplets from a cough or sneeze. Once infected, the virus can live in a person’s throat and intestines for weeks and can also contaminate food and water in some conditions.

Children aside, you may wonder if you’re still protected as an adult if you were vaccinated as a baby. The short answer is yes. But if you plan to travel to a high-risk country, including parts of Asia and Africa, or think you may have to work with polio patients or poliovirus samples, an IPV booster is recommended. And it’s never too late to get the vaccine series, even if you didn’t receive them as a child.

Be sure you are up-to-date on all the latest childhood immunizations recommendations, and discuss them with your child’s healthcare provider.