In 1979, the World Health Organization successfully eradicated smallpox, removing one of history's greatest killers from the face of the Earth. Now, 33 years later, we just might be on the verge of repeating that feat with polio.
Polio, which once killed or paralyzed a half million people each year in the 1940s and 1950s, has been on the run from scientists and health officials for some time now. While there were 52,552 recorded cases of polio worldwide as recently as 1980 - and that vastly underestimates the true total that year, which is estimated to have been as high as 400,000 - there were just 649 new cases of the disease last year. The Americas, Europe, the countries of the Indian Ocean, and much of the Pacific Rim has been polio-free for over a decade.
Polio is now on track to be the second human virus (and third overall, including the bovine disease rinderpest) to be certified eradicated, and the big breakthrough this past year has been in India, which has not seen a case of polio since January 2011. That means the country just completed its first polio-free year, leaving just three countries where the disease is still endemic: Nigeria, Pakistan, and Afghanistan. With 99% of incidences of the disease long since destroyed, that just leaves the 1%. Unfortunately, that 1% has proven almost intractable, with the efforts to get rid of it compared to "trying to squeeze Jell-O to death."
The BBC has a great article up on the recent success in eradicating the disease in India, as well as the challenges that still lie ahead in getting rid of the disease once and for all. It's well worth reading to get a sense of what is potentially the most important public health initiative currently underway, and why we are now so close to success after decades of work. Admittedly, even if we were o wipe out polio this year, we won't know until 2015 - the United Nations won't certify a disease eradicated until the world has gone three years without a case. Here's hoping we'll only have to wait until 2015.