The drop that eradicates polio

A health worker gives polio drops to a child during the National Immunisation day at a government children's healthcare centre in Amritsar, January 7. 

Polio cases in India shot up to 641 in 2006, with 17 more cases in the last week of December, pushing back India's polio eradication efforts by at least two years..  

Photograph: Narinder Nanu/AFP/Getty Images