I was excited to read on the news yesterday morning that the WHO has a plan in place to fully eradicate polio by 2018 (you can find that news story here). You can also read information on polio eradication from the CDC from this link.
Polio used to afflict hundreds of thousands of people every year. People who caught it (usually children) could die or suffer permanent paralysis. Unlike most viruses, it struck in the summer months. When I was in Pennsylvania a few weeks ago, our tour guide talked a bit about growing up in the age of polio. His mom wouldn't let him swim in the rivers or lakes because they believed the virus spread from the water. It is amazing to me that a kid who couldn't swim for fear of polio would grow up to be an old man in a world where polio no longer exists at all.
If the plan succeeds, this will be the second disease we've completely wiped through modern medicine (smallpox was the first).
In the US, as in most parts of the world, we no longer use the live polio vaccine. The live vaccine was (is) very effective against fighting polio, but it can actually cause polio in one out of a million doses. When hundreds of thousands of children were getting sick, paralyzed, and dying from the disease, that very minuscule risk was worth it. As the number of polio cases declined, the vaccine was switched to an inactivated one. It is slightly less effective, but it can't cause polio. As part of the initiative to eradicate polio, the WHO is now switching all of the live, oral polio vaccines to the inactivated one (which we already use in the States).
The polio vaccine is incredible. We started vaccinating against polio in 1955. Wikipedia reads: "The annual number of polio cases [in the US] fell from 35,000 in 1953 to 5,600 by 1957. By 1961, only 161 cases were recorded in the United States." Last year, there were fewer than 300 cases in the whole world! We are so close to completely wiping out a devastating disease. I find that nothing short of awesome.