More than 50 years since Jonas Salk discovered the first successful polio vaccine, the disease persists in developing countries. According to the Global Polio Eradication Initiative, 372 cases were reported in 2013, up from 223 in 2012.

So it's encouraging that India — which had 741 cases as recently as 2009 — appears to have finally eradicated the illness, with the last reported case occurring three years ago. Patralekha Chatterjee at the BBC News explains how it happened:

Children who suffered from severe bouts of diarrhoea did not fully benefit from the oral polio vaccine. So, community mobilisers started talking about the need for hand-washing, hygiene and sanitation, exclusive breastfeeding up to the age of six months, diarrhoea management with zinc and oral rehydration therapy, and routine immunisation, necessary to sustain the success of polio eradication. This holistic approach has paid off. India's polio campaign gathered momentum when it focused on marginalised and mobile people, and began working in earnest with religious leaders in Muslim communities to urge parents to immunise their children.

India's success puts us one big step closer to completely eradicating polio — something that seems, finally, achievable. Read the rest here.