As the world lauded Bill Gates' foundation for its largest humanitarian pledge ever - $50 million to help in the fight against the spread of Ebola in West Africa - the wealthiest man in America expressed excitement over the rise of philanthropy among the young, rich and successful.

"I see more and more [philanthropists] every year. … You know, our view is that you shouldn't wait until you're just on your deathbed," he told ABC News, "you should use your talent to help. … To be smart about philanthropy."

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Gates, ranked by Forbes recently as the wealthiest man in the US for the 21st straight year with a net worth of $81 billion, called the $50 million donation the foundation's "biggest emergency grant ever."

"It is a very tough situation we're in right now - an infectious disease gets into an urban area," he said. "You have the horrific fact that people are dying of Ebola but also the whole health system is shut down. … So it's going to take a while there, first getting on top of Ebola, and then restoring a good health system."

Gates said he hoped the move, coupled with the US response and aid, would help the medical community finally get hold of the epidemic.

At least 2,909 in West Africa have died from the Ebola virus and at least 3,000 more have been infected, according to the World Health Organization.

The US government committed at least $175 million and the US military plans to give $500 million in "humanitarian assistance" that would be redirected from its budget.

In addition, almost 3,000 American troops have been mobilized to offer support to field hospitals and training facilities for health employees.

With the $50 million pledge, monies are expected to be released in "flexible funds" to UN agencies and global organizations that can purchase medical supplies and support facilities treating the outbreak.

"Everybody's stepping up - the UK, France - but the US most of all," Gates said. "A lot of countries. A lot of people. A lot of heroes [are] stepping up to help out."