Could you patent the sun? The vaccine pioneers who gave children a future

In 1991 a three-year-old boy in northern Peru caught polio. He would be the last child in the Americas ever to be paralysed by the wild virus, and three years later the whole region, from Canada to Chile, was declared free of a disease that had once terrified parents everywhere.

The summers parents dreaded

For the first half of the twentieth century, polio came with the warm weather. It mostly struck young children, and while most infections passed quietly, about one in every 200 left a child with paralysis that would never go away. Some children could only breathe inside an iron lung.

In the United States the worst year was 1952, when the disease caused about 21,000 cases of paralysis. Scientists knew the virus came in three types and could be grown in the laboratory. What the world needed was someone to turn that knowledge into protection.

Jonas Salk and the people's vaccine

Jonas Salk was born in New York City to a Jewish family; his mother had arrived from Minsk at the age of 12. In 1947 he took charge of the Virus Research Laboratory at the University of Pittsburgh, funded by the National Foundation for Infantile Paralysis, the charity later known as the March of Dimes.

Salk developed a vaccine made from killed virus. Before asking anyone else to trust it, he gave it to himself, his wife and their children. In 1954 more than a million schoolchildren, proudly called the Polio Pioneers, took part in a nationwide field trial. On April 12, 1955, the results were announced: the vaccine was safe and it worked.

That evening the broadcaster Edward R. Murrow asked Salk on CBS who owned the vaccine. Salk replied that it belonged to the people, adding, "There is no patent. Could you patent the sun?" Lawyers for the foundation had already doubted that a patent could be won, but Salk's attitude never wavered. According to the Salk Institute, he never earned any money from the vaccine and wanted it distributed as widely as possible.

The effect was swift. In the two years before the vaccine was widely available, the United States averaged more than 45,000 polio cases a year. By 1962 the figure had fallen to 910. Salk went on to found the Salk Institute for Biological Studies in California in 1963.

Albert Sabin and the sugar cube

Albert Sabin was born in 1906 in Białystok, then part of the Russian Empire, and came to America with his family as a teenager in 1921. He believed a vaccine made from weakened live virus, swallowed rather than injected, could protect even more children, more cheaply. As Salk had, he tested it first on himself and his own family.

Large trials in the United States were slow to come, so Sabin worked with scientists in the Soviet Union. Between 1959 and 1961, about 77 million people there received his vaccine. The drops could be given on a sugar cube, needed no syringe and cost little to make, which meant it could reach villages and cities far from any hospital. The United States licensed it in 1961 and 1962.

Sabin, too, declined to patent his work, so that the price could stay as low as possible. He continued to live on his salary as a professor. His oral vaccine became the vaccine of choice for most national immunisation programmes and the backbone of the World Health Organization's campaign against polio.

“It's my gift to all the world's children.”Albert Sabin, developer of the oral polio vaccine, Quoted in Emerging Infectious Diseases (CDC), 2022

A world of volunteers

The two vaccines made a far bigger idea possible. In 1988, when polio still paralysed more than 1,000 children every day, the World Health Assembly launched the Global Polio Eradication Initiative, spurred on by the volunteers of Rotary International. Since then more than 2.5 billion children have been immunised, through the cooperation of more than 200 countries and some 20 million volunteers, many of them going door to door.

The results are among the great achievements of modern medicine. The World Health Organization estimates that there were about 350,000 cases of wild polio in 1988, in more than 125 countries. Cases have since fallen by more than 99 percent, and the wild virus now survives in only two countries. The Americas were certified polio-free in 1994, followed by the Western Pacific in 2000, Europe in 2002 and South-East Asia in 2014.

Drew Weissman and the long road to mRNA

Half a century after Salk's announcement, the story took a new turn in a university corridor. In 1997 Drew Weissman, an immunologist from Lexington, Massachusetts, who had trained in Anthony Fauci's laboratory at the National Institutes of Health, joined the University of Pennsylvania. Waiting at the department photocopier, he got talking with Katalin Karikó, a Hungarian biochemist who had struggled for years to convince funders that messenger RNA could become a medicine.

They began working together, Karikó making the RNA and Weissman working with the immune cells. Their early experiments made mice ill, because the body treated the synthetic RNA as an invader. Investors showed little interest, but Weissman's grants, largely from the NIH, kept the small lab going, and each promising result spurred them on. In 2005 they published the key discovery: by swapping in a chemically modified building block, they could slip mRNA past the immune alarm.

Fifteen years later that discovery underpinned the mRNA vaccines against COVID-19. Weissman and Karikó shared the 2023 Nobel Prize in Physiology or Medicine, and the Nobel Assembly noted that, together with vaccines of other types, more than 13 billion COVID-19 doses had been given worldwide, saving millions of lives. Weissman's lab has also worked with Chulalongkorn University in Thailand on an mRNA vaccine meant to help Thailand and neighbouring countries with fewer resources.

Children who simply grew up

The most remarkable thing about this story is how ordinary its results now seem. Hundreds of millions of children have run, played and grown old without ever knowing the fear their grandparents felt each summer. Most never learn the names of the people who made that possible.

Salk, Sabin and Weissman worked in different decades with different tools, but each spent years on patient, uncertain work for children they would never meet. The final stretch of polio eradication is still under way, and the mRNA technology Weissman helped unlock is now being explored for other infections and for cancer. The gift is still being passed on.