Bill Gates increases his contribution to the charity foundation that will supply basic childhood vaccinations to poor nations. The commitment from the Bill and Melinda Gates Foundation has been doubled to hit $1.5 billion.

Melinda Gates referred to the $750 million contribution made in 1999 to set up the Global Alliance for Vaccines and Immunizations as "the best investment we’ve made."

The foundation plans to donate another $750 million to the alliance over the next decade.

Mrs. Gates reported that the number of children vaccinated against hepatitis B exceeded 42 million, and the effort helped to prevent over 670,000 premature deaths from 2001 through 2003. The use of 991 million syringes was crucial in maintaining safety of the vaccinations.

The success of the venture will also depend on the amount the alliance will be able to raise from private donors.

Gordon Brown, the UK’s chancellor of the exchequer, is expected to offer a contribution that will match Bill Gates’ donation and urge other affluent nations to contribute another $1billion. Other nations that are expected to offer donations are Sweden and France. Norway pledged $290 million on Monday.