History Spotlight, 3/26

Dr. Jonas Salk announces his discovery of a vaccine for polio on this day in 1953. It is difficult for people of my generation to comprehend what a nightmare polio was. HIV/AIDS doesn't even begin to compare. Polio is, perversely, largely a disease of modern sanitation. Prior to the medical and sanitation revolutions in the late 19th century people were exposed to a whole raft of viruses on a daily basis, especially in the cities. As part of this, they picked up a low-level immunity to polio. Children with weaker immune systems still got it, but it wasn't on an epidemic level. Once sanitation levels increased, people's natural immunity went down and incidents of polio went up. By 1952, there were 58,000 cases of polio reported, with 21,000 of them leading to loss of motor function.

Polio spreads easily through human contact. No animals are known to contract it. Its usual avenue of transmission is through out old pal, the fecal-oral highway. Someone uses the bathroom, doesn't wash his hands (perhaps due to being evil), then shakes your hand. Then your wipe your nose with your hand or settle in for a gold-mining session and congrats, you've contracted polio. In places with group showers (summer camps, for example) the transmission gets even easier.

During most of the 20th century, medical science was on an onward-and-upward kick. A vaccine for smallpox, once the curse of everyone from serfs to kings, was developed and it seemed possible that any disease out there just needed some good old-fashioned science thrown at it and a cure would be found. With a disease ravaging the world's youth and with science at that point triumphant over many other types of disease, it was only natural that a race for a vaccine begin.

The first few attempts were unsuccessful. One variety, developed in 1936 required much more dead polio viruses for one dose than was feasible. Another version caused allergic reactions, but no immunity to polio. Still another version actually caused a number of fatal cases. In 1948, a researcher named John Enders successfully isolated and cultivated the polio virus, making it much easier to examine in the lab without having to go out and get samples in the wild. In 1952, Jonas Salk announced the creation of a dead virus vaccine that could be administered through injection. Five years after that, an orally administered vaccine was developed and the world breathed a sigh of relief.

These days, polio is on its way to following smallpox to the ash heap of history. Smallpox was announced as being completely eradicated in 1977. In 1988, the World Health Organization announced its plan to eradicate polio. Worldwide cases of polio went from 350,000 in 1988 to 1,300 in 2007.