October 24 marks World Polio Day. The vaccination against poliomyelitis is considered one of the greatest achievements in preventive medicine. It has prevented millions of cases of paralysis and saved hundreds of thousands of lives. It has pushed back a disease that, in the 1950s, still paralyzed thousands of children in Germany and caused many deaths. A recent study published in the Deutsches Ärzteblatt now shows: Despite these unprecedented successes, vaccination efforts must not wane.

“Containing polio is one of the greatest achievements of public health — that is, protecting the health of entire populations,” says Professor Dr. Oliver Razum of Bielefeld University, senior author of the paper. “But even in Germany, we must continue vaccinating against polio. Complete eradication of the disease will not be achieved anytime soon.”

The study, titled “Successes and Obstacles in the Late Phase of the Global Polio Eradication Initiative,” involved researchers from Bielefeld and Heidelberg, among others. It summarizes the history and current status of the global program launched by the World Health Organization (WHO) in 1988. Since then, the number of cases has been reduced by 99.99 percent. Yet the disease remains a global threat.

Why Polio Has Not Disappeared
Poliomyelitis, or polio, is caused by highly infectious viruses that primarily affect children. In 90 to 95 percent of cases, the infection causes no symptoms. However, a small proportion of those infected suffer permanent paralysis, particularly of the legs. In severe cases, the disease is fatal because it paralyzes the respiratory muscles.

While large parts of the world are now considered polio-free, so-called wild polioviruses continue to circulate in Pakistan and Afghanistan. Another growing problem is mutations of vaccine-derived viruses, which can cause new outbreaks in countries with low immunization rates. Due to international mobility, such viruses can also reach industrialized countries. Recently, they have been detected in wastewater samples from several European cities, including in Germany.

Funding Gaps and Vaccine Fatigue
The authors of the study also warn of emerging risks. International donors, such as the U.S. development agency USAID, are reducing their funding. As a result, resources for vaccination campaigns are shrinking — while at the same time, conflicts, weak health systems, and increasing vaccine skepticism exacerbate the problem.

Razum therefore draws a clear conclusion: “We must not rely solely on the goal of eradication. What matters most is achieving consistently high vaccination coverage everywhere in the world.” Physicians in Germany also play an important role in this effort. They should routinely check vaccination records and ensure that any missing doses are administered.

The study thus arrives at a sobering but clear conclusion: Polio will continue to challenge the global community for years to come. Yet with consistent vaccination, the disease can be prevented from once again becoming a threat.