Polio Travel Advisory: CDC Urges Vaccinations for 32 Countries

The Centers for Disease Control and Prevention (CDC) this week issued an advisory urging travelers to exercise “enhanced” precautions when visiting 32 countries where poliovirus circulation has been detected. This guidance comes as global vaccination rates decline, raising concerns about a resurgence of a disease once largely eradicated.

The affected destinations span Europe – including the United Kingdom, Germany, Poland, Spain, and Finland – as well as parts of Africa, such as Tanzania, and the Eastern Mediterranean region, including Israel, and Afghanistan. The CDC recommends that anyone planning travel to these areas verify they are up-to-date on their polio vaccinations, and consider a booster dose even if they completed the original vaccine series, which generally provides lifelong immunity for most individuals.

Polio’s Persistent Threat and Global Vaccination Trends

“Polio continues to be an issue and is an increasing issue in many countries of the world related primarily to decreases in vaccination,” explains Robert H. Hopkins Jr., MD, medical director of the National Foundation for Infectious Diseases (NFID). He emphasizes that for those fully vaccinated, the risk of contracting a polio infection is “extremely low — near zero.”

Polio is a highly contagious disease spread through fecal-oral transmission – meaning it spreads when someone ingests food or water contaminated with the feces of an infected person. The virus can too spread through direct contact. While most individuals infected with polio experience no symptoms, some may suffer mild symptoms like fever, fatigue, and muscle pain. However, in approximately 1 in 200 cases, the virus can invade the nervous system, causing irreversible paralysis. The World Health Organization (WHO) reports that 5 to 10 percent of those paralyzed ultimately die due to immobilization of their breathing muscles.

The introduction of the polio vaccine in 1955 and subsequent widespread vaccination campaigns led to the elimination of polio in the United States by 1979. However, the recent decline in vaccination rates globally is fueling renewed concern.

Understanding the Risks of Undervaccination

Currently, the CDC recommends four doses of the inactivated polio vaccine (IPV) for optimal protection as part of the routine childhood immunization schedule. However, vaccine hesitancy – driven by misinformation, cultural beliefs, distrust in institutions, and other factors – is contributing to decreasing vaccination rates for polio, as well as other diseases like measles, mumps, rubella, diphtheria, tetanus, pertussis, and varicella.

Data from the CDC indicates that 92.5 percent of kindergartners received the polio vaccine during the 2023-24 school year. While this remains a relatively high percentage, it represents a concerning downward trend. This trend is further complicated by recent discussions among CDC advisors regarding presenting polio vaccination as a personal choice rather than a routine recommendation, potentially impacting future uptake.

Hopkins warns that continued declines in vaccination rates could jeopardize the United States’ polio-free status. “The greatest risk is posed by unvaccinated U.S. Travelers being infected by polio internationally and bringing it back to their home communities,” he says. The global risk is growing as more countries experience underimmunization.

Afghanistan’s Ongoing Polio Challenge

The situation in Afghanistan remains particularly concerning. According to a report published in December 2024 by the CDC, Afghanistan reported 23 cases of wild poliovirus type 1 (WPV1) in 2024 as of November 1, representing the highest number of cases in four years. CDC report on polio eradication in Afghanistan This follows 12 WPV1 cases reported during the previous three years, including six in 2023. The report highlights ongoing challenges to polio eradication efforts, including intermittent restrictions on house-to-house vaccination campaigns, a crucial strategy for reaching vulnerable populations.

The CDC also notes that active cholera transmission is widespread in Afghanistan, adding another layer of health risk for travelers and residents alike. CDC Traveler Health – Afghanistan

Beyond Polio: Broader Implications of Declining Immunization

Adam Lauring, MD, PhD, chief of the division of infectious diseases at the University of Michigan Medical School, points out that many physicians today have never encountered a case of polio, leading to a potential underestimation of the disease’s severity. “I’ve never seen a case of polio as a physician, but I understand people in their seventies or eighties who have had polio — it’s something you carry with you your whole life and we don’t have any real treatments,” he explains. He emphasizes that the effects of polio can be devastating, leading to long-term disability or even death.

Dr. Lauring suggests that individuals, particularly those with compromised immune systems, should consider a polio booster “out of an abundance of caution,” given the resurgence of circulation. He also highlights the surprising nature of some of the higher-risk areas listed by the CDC. “You might not think before you go to London, ‘Hey, I better gain my polio shot,’” he says. “So stay informed about which areas have circulating virus.”

Staying Informed and Seeking Guidance

The CDC’s advisory underscores the importance of maintaining up-to-date vaccinations, not only for personal protection but also for safeguarding public health. The agency is stressing the demand for travelers to areas with increased risk to ensure they have received their polio shots and to consider a booster, even if previously fully vaccinated.

The CDC’s travel health page for Afghanistan provides further information on health risks and recommended precautions. CDC Afghanistan Travel Health Individuals planning international travel should consult with their healthcare provider to discuss their vaccination status and any potential risks associated with their destination.

Monitoring Polio Transmission and Vaccine Effectiveness

Public health officials are closely monitoring polio transmission patterns globally and evaluating the effectiveness of current vaccination strategies. Ongoing surveillance efforts are crucial for detecting new cases and identifying areas where vaccination coverage needs to be improved. The CDC and WHO continue to collaborate with national health authorities to strengthen polio eradication programs and prevent the re-establishment of the virus in previously polio-free regions.