03 | March | 2012 | Impressions

The effects of polio have been known since ancient times. Egyptian paintings and carvings depict afflicted people with withered limbs, and children walking with canes to support. The photo on the right is that of an Egyptian 18th Dynasty (1403–1365 BC) stele thought to represent a polio victim.

At the turn of the twentieth century, small, localized paralytic polio epidemics began to appear in the United States and Europe. During the first half of the twentieth century, polio epidemic outbreaks reached pandemic proportions in North America, Europe, Australia, and New Zealand.

Prior to the 20th century, polio infections, in most cases afflicted children six months to four years of age. It was rarely seen in infants before six months of age. Around 1950’s the peak age incidence of polio in the United States shifted from infants to children aged five to nine years; and almost one-third of the cases reported were in persons over 15 years of age. Hence, the rate of paralysis and death due to polio infection also increased during this time. In 1952, the United States, saw the worst outbreak of the polio epidemic in the nation’s history. Around 58,000 cases were reported that year out of which more than three thousand died, mostly children, and more than twenty thousand were afflicted with mild to disabling paralysis of the limbs.

In early 1950s, this scourge brought fear into the hearts of everyone, especially the parents of young and teenage children, as it was very well publicized with extensive media coverage of any scientific advancement that might lead to a cure. Thus, the scientists and researchers working on polio became some of the most famous of the century.

This burden of fear was lifted forever when an American dedicated researcher and virologist, Dr. Jonas Salk made the “impossible possible” by developing a vaccine to fight polio. Dr. Salk became world-famous overnight, but his discovery was the result of many years of painstaking research.

Jonas Edward Salk was born on October 28, 1914 in New York City to parents from Ashkenazi Jewish Russian immigrant families. Although his parents themselves did not have much formal education, they were determined to see their children study and succeed.

Salk had an immense passion for science. It was because of this that he finally chose medicine over law as his career goal. During his years at the New York University School of Medicine he stood out from his peers, according to Bookchin, “not just because of his continued academic prowess—he was Alpha Omega Alpha, the Phi Beta Kappa Society of medical education—but because he had decided he did not want to practice medicine.”

After obtaining his M.D. degree at the New York University School of Medicine in 1939, he worked as a staff physician at Mount Sinai Hospital in New York City. Later, he joined the University of Michigan as a research fellow. There, at the behest of the U.S. Army, he developed a vaccine for influenza. In 1947, he joined the University of Pittsburgh School of Medicine as director of the Virus Research Laboratory.

Dr. Jonas Salk - 02 — Jonas Edward Salk (Photo courtesy of the Salk Institute for Biological Studies)

While developing the influenza vaccine, he had observed that protection could be established using noninfectious, inactivated (killed) viruses. So, in Pittsburgh Salk developed the techniques that would lead to his polio vaccine. Vaccines against smallpox and rabies were induced by infecting by a living virus, but Salk thought otherwise – he conceived the idea that protective immunity could be induced, without infection by a living virus.

Basil O’Connor, president of the National Foundation for Infantile Paralysis, showed interest in Salk’s research. His organization decided to fund Salk’s research to develop a killed virus vaccine against paralytic poliomyelitis.

The vaccines developed by Sak’s team were tested first by injecting monkeys and then on patients who already had polio. Next, in order to test the vaccine on people who had not had polio, Salk injected himself, then his wife, his three sons, his laboratory staff, and volunteers. All of them developed anti-polio antibodies without encountering any bad reactions to the vaccine.

Finally, national testing of the polio vaccine began in 1954. One million children, ages six to nine, who became known as the ‘Polio Pioneers’ were injected: half of them were given the vaccine, while the other half received a placebo.

On April 12, 1955, Dr. Thomas Francis, Jr., of the University of Michigan, the monitor of the test results declared that vaccine to be safe and effective. When news of the vaccine’s success was made public on April 12, 1955, Salk was hailed as a “miracle worker”, and the day almost became a national holiday.

The average number of polio cases in the US was more than 45,000 in the two years before the vaccine was made widely available. In 1962, that number had dropped to 910.

Dr. Jonas Salk never patented the vaccine, nor did he earn any money from his discovery. He preferred to see it distributed as widely as possible. When the late television personality Ed Murrow asked him, “Who owns this patent?”, Salk replied, “No one. Could you patent the sun?”

This great humanitarian researcher died in June 23, 1995.

By 1988, polio had disappeared from the US, UK, Australia and much of Europe and South America, but remained prevalent in more than 125 countries. The same year, the World Health Assembly adopted a resolution to eradicate the disease completely by the year 2000.

The WHO Americas region was certified polio free in 1994, with the last wild case recorded in the Western Pacific region (which includes China) in 1997. A further landmark came in 2002 when the WHO certified the European region polio-free.

In 2012, Polio remains officially endemic in four countries – Afghanistan, Nigeria, Pakistan, and India. Despite so much progress, polio remains a risk with virus from Pakistan re-infecting China in 2011, which had been polio-free for more than a decade. India is on the verge of being removed from the list having not had a case since January 2011.