NEW YORK, January 31, 2011 /PRNewswire/ -- Bill Gates, co-chair of the Bill & Melinda Gates Foundation, argues the case for polio eradication and expanded childhood immunization in his third annual letter released today. The letter, a personal account of his priorities, also calls on governments to invest in foreign aid, even in the face of a tough economic climate.

"If societies can't provide for people's basic health, if they can't feed and educate people, then their populations and problems will grow and the world will be a less stable place," Gates writes in the letter. "Whether you believe it a moral imperative or in the rich world's enlightened self-interest, securing the conditions that will lead to a healthy, prosperous future for everyone is a goal I believe we all share."

Gates also emphasizes the need to continue improving U.S. schools, and urges more leadership, innovation and investment for issues like maternal and child health, malaria, HIV/AIDS and agriculture.

Gates focuses on polio eradication as a key example of the value of vaccines. Thanks to a global childhood immunization campaign, polio has been reduced 99 percent, and is on the threshold of becoming only the second disease ever eradicated.

"Getting rid of polio will mean that no child will be paralyzed or die by this disease," said Gates. "Any major advance in the human condition requires resolve and courageous leadership. We are so close, but we have to finish the last leg of the journey."

New donations to polio were announced last week from the U.K. government and from His Highness Sheikh Mohammed bin Zayed Al Nahyan, the Crown Prince of Abu Dhabi, which will reduce the gap of $720 million that is needed to fully fund polio eradication efforts through mid-2012. A recent study estimated that eradication could save the world up to $50 billion due to reduced treatment costs and gains in productivity.

Gates released his letter with a speech at the historic Roosevelt House, the former New York home of Franklin Delano Roosevelt, where the future president recuperated after being stricken with polio at age 39. Roosevelt and his law partner Basil O'Conner later launched the National Foundation for Infantile Paralysis, whose March of Dimes campaign mobilized the country against polio and raised millions of dollars to support the search for an effective vaccine.

Polio once threatened children worldwide, but there are now just four countries where polio has never stopped circulating - Afghanistan, India, Nigeria and Pakistan. Last year saw remarkable progress in Nigeria and India, where polio cases dropped by about 95 percent compared to 2009. But even a few isolated cases can cross borders and spark an outbreak.

Gates emphasizes that achieving polio eradication would energize the global health field by showing the real impact of health investments - particularly investments in vaccines. Last year, Gates called for the next 10 years to be the Decade of Vaccines, a vision of a world ten years from now where the global health community has come together to deliver life-saving vaccines to every child who needs them, and to invest in vaccines that don't yet exist.

"Not everyone can go into the field, or even donate. But everyone of us can be an advocate for people whose voices are often not heard," Gates writes. "I encourage everyone to get involved in working for solutions to the challenges those people face. It will draw you in for life."