The Centers for Disease Control and Prevention (CDC) issued an advisory this week advising Americans to take “enhanced” precautions when traveling to any of 32 countries where poliovirus is believed to be endemic.
These destinations include countries in Europe (such as the United Kingdom, Germany, Poland, Spain, and Finland), Africa (including Tanzania), and the Eastern Mediterranean (such as Israel and Afghanistan).
If you are planning to travel to these areas, the CDC recommends making sure your polio vaccination is up to date and considering getting a booster shot, even if you have previously completed the full polio vaccine series. This is said to provide lifelong immunity for most people who receive the vaccine.
“Polio remains a problem and is a growing problem in many countries around the world, primarily related to declining vaccination coverage,” said Robert H. Hopkins, Jr., MD, medical director of the National Foundation for Infectious Diseases (NFID).
“If you are fully vaccinated, your risk of contracting polio is extremely low, almost zero,” Dr. Hopkins says.
Why is polio dangerous?
Polio is a highly contagious disease. The virus lives in feces and can be spread if an infected person does not wash their hands properly after defecating (pooping). Poliovirus can also be spread through contaminated water and food.
Most people with polio have no symptoms, but some may experience mild problems such as fever, fatigue, stiffness in the arms or back, or pain in the arms or legs. However, once the virus invades the nervous system, one in 200 people will experience irreversible paralysis. According to the World Health Organization (WHO), 5 to 10 percent of paralyzed people die when their respiratory muscles stop working. There is no cure for polio.
With the introduction of polio vaccination in 1955 and widespread implementation of vaccination efforts, polio was considered eradicated in the United States by 1979.
Adam Loring, MD, chief of the division of infectious diseases at the University of Michigan Medical School in Ann Arbor, suggests that now that polio has been eradicated, many people may not realize how serious the disease is.
“As a doctor, I’ve never seen a case of polio, but I know people who got it in their 70s and 80s. Polio is something you carry with you all your life, and we don’t have a real cure,” he says. “The disease can affect the muscles that help people breathe, so the effects can be severe, with some patients losing the use of their arms and legs and ending up on ventilators.”
Risk of under-vaccination
Polio vaccination is now part of the routine childhood immunization schedule, and the CDC recommends four doses of inactivated polio vaccine (IPV) for maximum protection.
However, vaccine hesitancy has increased in recent years due to misinformation on social media, religious and cultural beliefs, and distrust of institutions.
According to the CDC, vaccinations for measles, mumps, rubella (MMR), diphtheria, tetanus, pertussis, and varicella, as well as polio, are decreasing among kindergarteners. According to agency data for the 2024-25 school year, 92.5% of kindergarteners received the polio vaccine.
Coverage may fall further as influential advisers to the CDC emphasize that polio vaccination should be presented to the public as a personal choice rather than a routine recommendation.
If this downward trend continues, the U.S. could eventually be at risk of losing polio-free status, Hopkins said.
“The greatest risk is posed by unvaccinated U.S. travelers acquiring polio internationally and bringing it back to their home communities,” he says. The risk of polio is increasing worldwide as countries increasingly run out of vaccinations.
Therefore, the CDC emphasizes that travelers to higher-risk areas should make sure they have received the polio vaccine and consider getting a booster shot even if they received a full series of polio vaccines as children.
“With this resurgence in polio outbreaks, I think some people, particularly those who are immunocompromised, may seriously consider getting a booster shot out of an abundance of caution,” Dr. Loring said. “These injections are safe and effective. We encourage you to contact your doctor to discuss this.”
He also noted that some of the high-risk areas listed may be surprising to many American travelers.
“Before you go to London, you might not think, ‘I should get a polio shot,'” says Laurin. “So stay informed about where the virus is prevalent.”
