The vaccination of three quarters of the world’s children has proven to be one of the most cost-effective public health interventions on record. Nevertheless, the disease killed 454,000 children in 2004, leaving others blind or deaf. Two thirds of the world’s unprotected children live in six countries: China, the Democratic Republic of the Congo, India, Indonesia, Nigeria and Pakistan.

Latin America and the Caribbean made the greatest strides in immunizing children, with sub-Saharan Africa showing significant progress as well. Sub-Saharan Africa also achieved the largest reduction in deaths from measles: a decrease of nearly 60 per cent between 1999 and 2004.

This overall progress masks wide inequalities within countries: In Chad and Nigeria, for example, children of educated mothers are two to almost four times, respectively, more likely to be vaccinated than children of mothers with no education. The gaps are even wider when children from richer and poorer households are compared.