By Janet Fang
Posting in Technology
The last child paralyzed by polio got sick exactly one year ago this week. India's success was due to a more effective vaccine and creative ways of finding high-risk children.
PAIN is a problem, when it comes to ridding the world of polio. That’s Pakistan, Afghanistan, India, and Nigeria – the 4 countries that stood in the way of a global campaign against the disease.
Those countries have never managed to stop the spread of polioviruses in their borders, and they continued to send viruses off to places that have stopped transmission.
BUT NOW! The last child paralyzed by polio in India got sick on January 13, 2011, and surveillance for wild polioviruses in sewage has not turned up the pathogen in more than a year. Her name is Rukhsar Khatoon, pictured below, and she lives in Shahapar village, West Bengal.
If India produces 12 straight months of polio-free surveillance data, it will be removed from the list of countries where polio is considered endemic.
A statement will be issued by the Global Polio Eradication Initiative on the anniversary of that last case (but with the time it takes to process pending lab tests, it may be mid-February before there is official word).
"This is huge for us. It has taken more than a decade and tens of millions of health-workers, managers and a lot of mobilization to get to this point," says Hamid Jafari from the World Health Organization's National Polio Surveillance Project, based in New Delhi. And also $2 billion.
Eradication programs seem to have 2 distinct problems:
- In Nigeria, where some Muslim parents refused to vaccinate their kids on religious grounds, and in conflict-torn countries like Afghanistan, where safe access is a challenge, the programs were failing to vaccinate all children.
- In India, however, the failure was on the part of the vaccine.
For well nourished and healthy children, it only takes 3 doses of oral polio vaccine. But malnourished children who suffer from diarrhea and live where sanitation is poor can’t mount a protective immune response as easily. In India, children who have been vaccinated 10 or more times could still get polio.
New vaccines that targeted first 1 and later 2 strains of polio, rather than all 3, were introduced and began to make real progress.
But locating and vaccinating all the vulnerable children was still a seriously difficult. On the twice-annual national vaccination days, 2.3 million vaccinators (pictured above) visit 209 million households. So, the country used transit points – train stations, bus depots, highway intersections – as distribution centers. And special efforts are made to locate and map where migrant families set up camps.
So, hooray! However, or on the other hand, India – which used to export polioviruses – is now vulnerable to reinfection from its neighbors. Each Indian state has drawn up emergency response plans for when (or if) that should happen.
From Scientific American.
Images of India One Year Polio-Free by Gates Foundation via Flickr
Jan 10, 2012