The time has finally come for the last This Week in History column of the 2025-2026 school year. Over these past few months, it has been a lot of fun writing about different events over the course of time and learning something new about the past each week. For my final column, I want to dive into the Salk vaccine, an innovation that revolutionized immunization and drug trials in the 1950s. On April 26, 1954, testing began for the vaccine, with high hopes that it could eradicate the infectious disease poliomyelitis or polio.
As a disease, polio has existed since prehistoric times, with depictions of it found in various art forms throughout history. It can be contracted through water contaminated with the virus and through droplets from the sneezes or coughs of those infected. In the 19th and early 20th centuries, epidemics of the virus occurred, making it widely feared for its potential lifelong paralysis effect. With no cure, the need for a vaccine was of the utmost importance.
The vaccine itself was developed by Jonas Salk, an epidemiologist who worked on a flu vaccine at the University of Michigan before beginning his work at the University of Pittsburgh to develop an Inactivated Poliovirus Vaccine (IPV). Finding success in the early 1950s, Salk first tested the vaccine on both himself and his family in 1953, a year before the official vaccine trials began, according to the article “History of the polio vaccine”published by the World Health Organization.
The testing process was one of the largest and most publicized clinical trials, involving 623,972 children in the United States and more than a million others in control groups, according to the article, “‘A calculated risk’: the Salk polio vaccine field trials of 1954” by Marcia Meldrum. It was sponsored by the National Foundation for Infantile Paralysis, currently known as the March of Dimes, an organization founded by President Franklin D. Roosevelt. At the age of 39, Roosevelt was diagnosed with polio and experienced infantile paralysis, losing feeling from the waist down on a trip to Campobello Island in New Brunswick, Canada. His own struggle with the disease led him to found the National Foundation for Infantile Paralysis, which still works today to end preventable maternal health risks and deaths. Through grassroots organizing and fundraising, the organization was able to fund research for the vaccine.
Statistically, scientists approach the trials by testing the vaccine with the demographic that had the highest incidence of polio paralysis: grade school children in counties with the highest case rate of polio. The foundationsent volunteers to school districts to encourage parental consent for their child to participate in the trials.
The vaccine proved to be a success and was 80%-90% effective in preventing paralysis, according to Meldrum. Polish scientist Albert Sabin developed another type of polio vaccine shortly afterward: the oral poliovirus vaccine (OPV), which could be delivered via a sugar cube. Easier to produce and deliver, the OPV eventually replaced the Salk vaccine, but it can cause issues for under-vaccinated communities, as the weakened form of the virus can begin to circulate.
The history of the polio vaccine is something that I think we should continue to learn about today. Vaccines have become a topic of controversy, and I believe that people forget what life was like without them. In today’s world, it is unlikely that a clinical trial for a vaccine on school-age children would ever occur, partly because drug trial methods have changed, but also because of the socio-political landscape. Regardless, it’s important to consider the positive changes that vaccinations have contributed to public health and rejoice in the rarity that we rarely see the need for an iron lung.