An Egyptian stele thought to represent a polio victim, 18th Dynasty (1403–1365 BC) Credit: Wikimedia Commons
Polio has existed for thousands of years in the human population; there's even evidence in Egyptian hieroglyphics of people with one limb withered, but otherwise healthy. The polio virus spreads by oral-oral and fecal-oral routes, so sanitation issues in the growing cities of the industrialized world increased its spread. It was not until major epidemics in the 1880's in Europe and later in the United States that people saw the need to take action to find ways to prevent the disease.
Two types of polio vaccines were developed and proved successful in large scale immunization programs throughout the world. Hilary Koprowski, who passed away last week, produced a vaccine in 1950 that used a polio virus that was weakened and could not actively make people ill. The more famous vaccine produced by Jonas Salk in 1952 used a weakened version of the virus that was then rendered inert and unable to infect any cell. In both cases the immune system would see the weakened virus and make antibodies, rendering the person immune.
Currently, the most used polio vaccine was developed by Albert Sabin in 1954 and is more than 95 percent protective against all polio subtypes with just a single drop in the mouth of patients.
If we have such an effective vaccine, why has polio eradication taken so long?
The answer lies in the way the polio virus infects the human body. As it turns out, polio shows no symptoms in around 90 percent of all infected people. In other words, they can easily be carriers and infect others without ever knowing they even carried the disease. In fact, only one percent of people infected with the virus have it progress to infiltration of the central nervous system, attacking motor neurons responsible for controlling muscle movement and resulting in paralysis.
So, while we are getting closer and closer, the virus continues to just barely slip through our grasp.
But things are about to change.
A large effort is being made now by the Global Polio Eradication Initiative and their announcement of eradicating polio by 2018 using $5.5 billion of donated funds. The effort focuses on Afghanistan, Pakistan, and Nigeria — the last remaining counties with polio outbreaks.
Putting money towards eradication efforts has had successes. India, a country with a population well over one billion, has not had a polio case in years. Almost a quarter of a billion vaccinations were given out in the country and over 172 milllion children were immunized. The Indian government equipped people with the latest technology to vaccinate people in small villages. In small towns each house was identified by satellite imagery and GPS coordinates and a massive checklist of most rural homes in the country.
But there have been setbacks. Immunization efforts in Pakistan took a turn for the worse after the CIA infiltration and killing of Osama Bin Laden. Workers who were running a CIA backed 'vaccine drive' in Abbottabad were gathering intelligence for American forces. The backlash resulted in militants killing real vaccination workers throughout the country. Similar stories are heard in Afghanistan and Nigeria where people who vaccinate children are constantly at risk of being gunned down in order to save children's life.
Rumors were also spread that the United States was trying to sterilize children, so they would be unable to reproduce and the vaccines were their way doing this. Other whispers that have made parents and communities in those countries scared to have their children vaccinated are rumors of a secret plan to further spread HIV, the virus that causes AIDS.
To combat these misunderstanding and cultural differences people need to be educated as to the value of vaccination for not only their children and their community, but for the world as a whole. Myths about the vaccine need to be dispelled and communities need to be shown that rumors are just that. Sending people to vaccinate children in countries that have a combined population of over 200 million and where many live in rural areas is difficult and requires advance technology, dedication and the funding to make polio a thing of the past.