Wednesday, February 9, 2011

A World Without Polio?

According to an article in Nature, we could soon live in a world where the wild poliovirus doesn't exist. Many people may be somewhat shocked to know that it does still exist, though. Polio isn't a particularly prominent virus anymore, much in the way that smallpox has been exterminated, polio has been eliminated from civilized nations. In the article it estimates roughly 99% of poliovirus has been exterminated. It is a problem that has mostly been relegated to the past. But with the recent announcement from the Bill & Melinda Gates Foundations that it is dedicated to the complete eradication of the wild poliovirus by 2012, it may soon be that polio truly is a problem of the past to everybody.

However even with the backing of the Bill & Melinda Gates Foundation and the various other organizations that are currently at work trying to get rid of this sickness, there still are possible speedbumps for the 2012 goal as the article points out. Financing is the first problem any sort of campaign will face. The projected amount required rests at $1.81 billion (US), though $1.1 billion has already been raised for this objective. Various sources such as the Gates Foundation and several governments have pledged additional sources in the last few weeks.

Logistics is yet another issue that the campaign against polio will face. It is endemic chiefly to 4 nations: Pakistan, India, Afghanistan, and Nigeria. But it is often very difficult to truly declare an area polio-free. This is due to the fact that polio only causes notable symptoms, including paralysis, in about 1% of its hosts. The rest are simply carriers for the virus. The silent nature of the virus also appears in the fact that it often reappears in areas that have previously been free of reported cases for a long time. However, these outbreaks are often short-lived as a relatively small number of people are not vaccinated and the virus burns out quickly.

Polio, much like many diseases that can be treated quite well, manages to squeeze by assisted by the fact that it is common in areas of conflict and poverty. This makes getting the means to vaccinate people to the people can be a challenge in and of itself. On top of this, in many of these regions there are demographics of people who fear that the oral vaccination of polio will cause medical problems and simply refuse to take it.

Even once the proclaimed 'last push' to get rid of polio is underway, it is likely that it will not be the final 1% to put the wild poliovirus at 100% eradicated. Experts say that there is more than likely other small, undetected pockets of people still are risk of infection that will have to be cleaned up and vaccinated before we can claim that polio is gone. What's more, there is still a risk of polio making flares from people who respond poorly to the vaccination and see the effects of polio from being vaccinated. These cases have been documented in the past to be able to transition to virulent stands of the virus. However, this sort of problem could be counteracted towards the movement away from the orally-administered vaccine to that of an inactive/weakened strand of polio that will not be able to make the jump to a 'vaccine derived polio virus'. It is an incredibly intensive process to be able to stamp out a virus from the face of the planet, but it may not be too long before the world can say goodbye to polio.

-Phillip Hunt


  1. This is a great article! More positives coming from the scientific world. I was one of the people who thought Polio was extinct. If I were to guess where Polio was still present, I would have guessed parts of Africa, not mostly in the Middle East. On a side note, I feel it is remarkably unselfish for Bill and Melinda Gates to contribute so much money for a world cause. It is a great feat of man-kind to conquer a virus that had previously taken countless lives.

    Posted by Reed Allen

  2. I feel like there is not enough reasoning to why Polio is not longer a prominent virus. What has caused the natural decline in its popularity, or where is the evidence to prove that it will not become a problem later in the next fifty years? Smallpox hasn't necessarily been eliminated, there are still very rare cases that occur. How can we group smallpox and polio together when there has never been a cure for either, both diseases simply declined in popularity.

  3. It's good that the article mentions smallpox for comparison. I think the article is correct and perhaps even understating the possible difficulties in trying to exterminate 100% of the poliovirus. Smallpox was extremely virulent and deadly, which made it relatively easy to track down. And, since it mostly killed its carriers, the actual host populations went down dramatically once extermination efforts commenced. With Polio none of these advantages are in place. Having silent carriers that show no symptoms is a huge detriment to the project, and makes me question whether achieving 100% extermination is even possible, let alone doable within the next year.

    Posted by Derrick Xu

  4. The article is a bit scarce on the reasons as to why Polio has seen such a sharp decline in popularity. This prompted me to look around for some information regarding that.

    The polio virus is not airborne, it is spread oral-oral contact or fecal-oral contact, which means that it is spread through close contact or the eating/drinking of contaminated substances. Because of this polio is contracted between people. And thus, there needs to first be an infected individual in order for it to spread through the general population. Through means of mass-immunization it is possible to restrict polio to only a small number of carriers who haven't be immunized. This explains why there is such a small number of cases now that we have a viable vaccine for it. And as long as people continue to be immunized, makes the risk of a resurgence of polio very small. As to the 100% extermination, it seems reasonable to expect there will always be a few secluded cases. But as long as the general public is immune, then those cases can be managed to effectively provide 100%, while in reality it will be 99.some absurd decimal%.

    -Phillip Hunt