The World Health Organisation recently announced that India has gone for more than one year with no new cases of polio. Polio is a highly contagious viral disease often spread through contaminated drinking water.
Most people who contract poliovirus show no symptoms, but in a small percentage of cases, the effects can be devastating. Once it is in the body, it can attack the nervous system, causing irreversible paralysis. In some extreme cases, the muscles responsible for breathing fail, leading to death.
Polio used to be more common, but improved sanitation and the invention of a vaccine led to a decrease in cases in the developed world, although it remained a problem in the developing world. In 1988 the Global Polio Eradication Initiative was launched. Since then the number of cases has dropped from around 350 000 to less than 1500.
India was one of only four countries where polio was endemic – that is, a country where polio has never been eradicated. Until recently, there were more polio cases in India than the other three endemic countries combined. A concerted vaccination program combined with improving water sanitation is believed to be responsible for this result. If there are no new cases reported for three years, India will have won the fight to be certified as having eradicated polio.
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