Bill Gates warns that despite Saudi Arabia's $500m pledge to fight polio, a $1.2bn funding gap remains in the Global Polio Eradication Initiative.

Bill Gates warns that eradicating polio is not guaranteed, despite $500m Saudi pledge to fight the disease over the next five years. There remains a $1.2bn funding gap in the $4.8bn budget for the Global Polio Eradication Initiative up to 2026. Saudi Arabia, which has supported polio eradication for over 20 years, has now become one of the largest national donors to the cause, alongside the US.