Polio in the U.S.: What You Need to Know

enterovirus-polio enterovirus
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In mid-July 2022, the New York State Department of Health identified a case of polio in a person living in Rockland County who had not been vaccinated. 

The 20-year-old man developed paralytic polio. He likely got the virus from someone who had been vaccinated with the oral polio vaccine, which is not used in the United States anymore.

In some cases, the oral polio vaccine can lead to “vaccine-derived” polio infections because it’s made with live poliovirus (the vaccine used in the U.S. contains an inactivated virus).

Over the next few weeks, testing of wastewater found the poliovirus in samples in Rockland County and Orange County—which are 60 and 80 minutes north of New York City by car, respectively. They have not identified more cases of polio in the state.

On August 26, poliovirus was found in wastewater in Sullivan County, about an hour north of Rockland County. In early September, poliovirus was found in wastewater in Nassau County.

On September 10, the governor of New York declared a state of emergency in hopes of encouraging people to get vaccinated against polio.

The Centers for Disease Control and Prevention (CDC) have sent scientists to New York to investigate and offer polio vaccinations to people in the area who are unvaccinated.

What Is Polio?

Poliomyelitis (polio) is an infectious disease caused by a virus. Infected people shed the virus in their feces, which can contaminate food and water and spread to other people. It’s less likely, but they can also spread the virus to others when they cough or sneeze.

The polio virus attacks the nervous system. The symptoms of polio can include headache, fever, nausea and vomiting; and pain and stiffness in the limbs. A person with a mild case of polio may recover fully from these symptoms within a few days to weeks.

A small percentage of people get life-threatening illnesses from polio. For example, polio can cause inflammation in the brain (meningitis), which can be fatal.

One of the most serious, but rare, outcomes of polio is becoming paralyzed. Paralysis can start within a few hours of when a person is infected. In some cases, it’s severe enough to affect the muscles that help with breathing and a person will die.

However, up to 90% of people who have been infected with polio have only mild symptoms or no symptoms at all. They can still spread the virus to others.

Who Gets Polio?

Today, most cases of polio occur in children under the age of 5. However, any person can get polio, especially if they are not vaccinated.

There’s no cure for polio and since it’s caused by a virus, it can’t be treated with antibiotics. If a person gets seriously ill from polio and develops paralysis, they may need physical therapy and medications that help their muscles.

Polio is also a vaccine-preventable disease. It’s included as a routine childhood immunization in most parts of the world, which has helped us get closer to eradicating it.

Didn’t We Eradicate Polio?

We have eradicated two strains of the poliovirus, but there’s still one left. Polio won’t be eradicated until we stop the spread of the third type, too.

Vaccination programs have made polio far less of a worry for many people around the world than it was throughout history. We’re in the “last leg” of the global polio eradication effort, but we’re not there yet.

Is It Possible to Eradicate Polio?

Some diseases cannot be eradicated because they can survive in both humans and animals and spread back and forth between them—for example, influenza viruses.

However, the polio virus can only survive in humans, which means that it’s possible for us to eradicate it.

So, why haven’t we? Well, polio presents a few challenges:

  • People do not get vaccinated and do not vaccinate their children. Unvaccinated people are more at risk of getting polio and giving it to other people. They also make it easier for the poliovirus to resist eradication, since it needs to get inside a human to survive.
  • Violence and humanitarian crises have made polio vaccines inaccessible in some countries. The Taliban banned door-to-door polio vaccination efforts in remote rural areas of Afghanistan in 2018 and only allowed them to resume last November. And a Taliban-linked group in northwest Pakistan has targeted teams providing polio vaccines in the region, reportedly killing as many as 70 of the teams’ personnel in the past decade.
  • The virus can be hard to track. It may take weeks for an infected person to have symptoms of polio and some people never have symptoms. An infected person can keep spreading the virus directly for about 2 weeks after being infected. The virus can survive in feces for several weeks, potentially contaminating food and water.
  • The COVID-19 pandemic. The global COVID pandemic needed to use up a lot of public health resources around the world, which meant that other infectious disease goals had to be put on hold.

The only countries where polio still circulates (is endemic) are Afghanistan and Pakistan, but cases also pop up throughout Africa.

The polio virus does not exist “in the wild” in the U.S. Usually, it’s brought here by someone who was traveling and is limited to just that person and they don’t spread it to someone else.

Elimination vs. Eradication

Polio has been eliminated in the U.S. for more than 30 years thanks to a safe and effective vaccine.

However, polio will not be eradicated until the last wild poliovirus is no longer a threat in the world and we no longer need prevention strategies like vaccines.

Sometimes, when public health departments do surveillance on wastewater, they find evidence of infectious diseases—including the polio virus.

For example, the polio virus was found in wastewater samples in the U.K. earlier this summer. The U.K. government reminded citizens that it’s important to make sure that they, and their children, are up to date on their vaccines.

Do I Need a Polio Booster?

As long as you were vaccinated against polio as a child, you probably don’t need a booster. If you or your child have not been vaccinated or you missed a dose, the CDC recommends that you get caught up.

The CDC only recommends a polio vaccine booster for people who are at high risk for catching the virus—for example, people working in labs where the virus is being researched.

Elsewhere in the world, governments might take a different approach. For example, after poliovirus was found in sewage samples in July, public health authorities in the UK decided to offer children in London a polio booster shot.

Could Polio Be Like COVID or Monkeypox?

Polio, COVID-19, and monkeypox are all caused by viruses, but they’re very different diseases. It is not likely that polio could not become a global pandemic like COVID or even a widespread outbreak like monkeypox.

There are a few reasons that polio isn’t likely to become a situation like the COVID pandemic or the monkeypox outbreak:

  • The virus that causes COVID as well as the virus that causes monkeypox can both live in animals and humans. The virus that causes polio can only survive in humans. That’s why polio is a good candidate for eradication, while monkeypox and COVID could not be eradicated.
  • Polio, COVID, and monkeypox can all be spread between people, but some more easily than others. COVID is very contagious because a sick person can breathe out particles into the air that other people can easily breathe in. Monkeypox and polio are more likely to spread through close contact with an infected person—for example, touching someone who is sick.

There are safe and effective vaccines for COVID, polio, and monkeypox. However, that does not mean that everyone will get vaccinated or vaccinate their kids. In the case of COVID, even getting people vaccinated hasn’t meant the virus is under control. We’re still trying to “catch up” with the virus as it evolves and make vaccines and boosters that will be effective against variants.

10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  2. World Health Organization. Poliomyelitis (polio): symptoms.

  3. World Health Organization. Poliomyelitis (polio).

  4. World Health Organization. Poliomyelitis.

  5. Global Polio Eradication Initiative. The vaccines.

  6. UNICEF. Eradicating polio.

  7. Centers for Disease Control and Prevention. Epidemiology and prevention of vaccine-preventable diseases. Poliomyelitis.

  8. Tharwani ZH, Shaeen SK, Arshad MS, et al. Polio amid a humanitarian crisis in Afghanistan: challenges and recommendations. Lancet Infect Dis. 2022;22(2):168-169. doi:10.1016/S1473-3099(22)00004-4

  9. Council on Foreign Relations. Why hasn’t the world eradicated polio?.

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