How polio vaccine invented

Added: 2026-05-20

[00:00:00]Back in the mid 1900s, polio was a terrifying disease that paralyzed thousands of children every year, leaving the world desperate for a cure. Enter a brilliant scientist named Jonas Salk. Instead of trying to cure the disease after someone caught it, Salk wanted to teach the human body how to fight it off beforehand. He came up with a clever and safe idea. He took the actual polio virus and killed it using a chemical called formaldehyde. This meant the virus was basically a harmless dead shell that could no longer make anyone sick, but it still looked exactly like the dangerous polio virus to the human immune system. Salk then injected this dead virus into healthy volunteers, including himself and his own family.

[00:00:47]When the body's defense system saw these harmless virus shells, it immediately created special fighter cells called antibodies to destroy them. The amazing part is that the body remembers how to make these exact weapons forever. So, if the real-life polio virus ever tried to attack a vaccinated person later on, their body already knew exactly how to destroy it instantly. Salk's vaccine was proven a massive success in 1955, and shortly after, another scientist named Albert Sabin created a live but weakened version of the vaccine that could easily be swallowed on a sugar cube, teaming up to nearly wipe out polio worldwide.