Yes, The Polio Vaccine is Still Critical For Kids—Here's Why

The first case of polio in the United States after nearly a decade was confirmed in New York on July 21, 2022. State and county health officials reported that the virus was identified in Rockland County and transmitted by someone who received the oral polio vaccine. Experts believe the infection may have originated outside of the United States since the oral form of the vaccine has not been administered in the country for more than 20 years.

The re-emergence of the polio virus comes just days before the start of National Immunization Awareness Month (NIAM), which is recognized every August. Each year, NIAM brings awareness to the importance of vaccines for people of all ages. 

There is no cure for polio, but the vaccine is proven to be 99% effective at protecting against it. The three-dose polio vaccine is part of the Center for Disease Control and Prevention’s (CDC) standard child and adolescent immunization schedule. Officials are now urging those who have not been vaccinated against polio to get immunized right away. 

What Is Polio?

Polio is a viral, potentially life-threatening disease that can affect the nervous system and cause muscle weakness, though many people who contract the disease are asymptomatic. It has been around since the late 1800s, but outbreaks of the disease became more frequent in the late 1940s. Thousands of people were left disabled each year, and infections were typically highest in the summer months. 

“If you took 100 children, and they all acquired polio, somewhere in the neighborhood of 80% of them would have no symptoms at all,” explains Marc Foca, MD, pediatric infectious disease expert and associate professor of pediatrics at Children’s Hospital at Montefiore Hospital. “And then the other 20% would eventually develop symptoms of what most people would consider a viral illness—a headache, fever, malaise, maybe some diarrhea.”

A much smaller population of infected people would develop paralytic polio, Dr. Foca adds, which causes paralysis, often in the person’s legs. Polio-induced paralysis can sometimes be fatal if the paralysis extends to the breathing muscles. 

Thanks to the polio vaccine, which was developed in 1955, the virus has been essentially eradicated from the United States, with the last case of natural infection in the country confirmed in 1979.

How Does Polio Affect Children?

Though polio has the same effect for both children and adults, kids are more susceptible to the virus, as it can be spread through contact with infected fecal matter. And, as Daniel Johnson, MD, professor of pediatrics at the University of Chicago Medicine explains, children are notorious for poor hygiene because they just don’t know any better. 

“If a child acquires the virus and they're shedding it, and they go to the bathroom [without washing] their hands, they can spread the virus to someone else through what's called a fecal-oral route,” Dr. Johnson says. “So their stool contaminates someone else's hands, and then the person acquires the virus when they move their hand to their mouth.”

Occasionally, polio can spread through sneeze or cough droplets from an infected person, but it’s not as common. 

When Can Children Receive Polio Vaccines?

According to the CDC, about 93% of people over the age of two in the United States are fully vaccinated against polio. Children usually receive their first polio vaccine dose at two months old, their second dose at four months, and the third shot between six and 14 months old. A fourth dose is recommended when a child starts school, around four to six years old. Public schools in all 50 states and Washington D.C. require the polio vaccine, among other immunizations, to attend. 

Side effects from the vaccine are mild, Dr. Johnson adds, and typically manifests as pain in the injection site. A very small percentage of people are allergic to its components. The minimal side effects and nearly 100% effective rate makes the vaccine a remarkable tool for protection.

“There's definitely been a drop-off in routine immunizations,” Dr. Foca says of recent months. “And I don't believe it's because people are more fearful of vaccines. I believe people have been more fearful of going into large crowded spaces with the pandemic, and they're putting off routine medical care and vaccinations for their children.”

The recent case of polio in New York drives home the importance of being vaccinated. Officials reported that polio has been detected in wastewater of two counties in New York, meaning the virus has been spreading amongst the community for months.

For those who are vaccinated, the recent news isn’t much of a concern, as the vaccine provides lifelong immunity. But for the unvaccinated, Dr. Johnson emphasizes, one case can be indicative of a larger threat.

“We know that for every one case of paralytic polio, there are dramatically more people who have acquired the virus and may be shedding it in their stool for weeks,” Dr. Johnson explains, adding, “They may eventually come into contact with someone who's not immunized and then lead to a risk of developing paralytic polio.”

Dr. Foca points out that, in order for no one to get sick, we have to largely rely on everyone who can receive a vaccine getting one. "[There are people] who can't be vaccinated...because of immunologic conditions like a transplant, or rheumatologic conditions like rheumatoid arthritis [that require] medications that may suppress their immune system," he adds. "So this country relies on citizens to follow these recommendations in order to prevent lots of other people from getting sick.”

A Word from Verywell

The recent case of polio in New York might be alarming, but experts point out that it's not a cause for concern for most people who have received the standard set of immunizations. If you have questions about your child's vaccination status, be sure to reach out to your child's pediatrician or healthcare provider.