"There's no reason only poor people should have the experience," the billionaire said, before adding that the mosquitoes were not infectious.
Gates was making the compelling point that, even if an issue like malaria doesn't directly affect you, you should still care. At that time, he noted, more money had been invested into researching hair loss drugs because, when it comes to baldness, "rich men are afflicted."
Malaria, meanwhile, is present mostly in poor, tropical areas of the world, where it can be devastating.
With this memorable demonstration, Gates won over his listeners by using a number of effective presentation tactics, including a visual aid, a direct interaction with the audience and even humor. "Baldness is a terrible thing," he joked.
A year later, he gave another presentation at TED on the future of the world's energy, and he recalled how well the 2009 audience had responded. He even replicated the experiment, this time with fireflies to serve as an example of a "gimmicky solution" to the energy crisis. The audience laughed and, later, gave him a standing ovation.
Since 2009, the Bill & Melinda Gates Foundation has made real progress in its fight against malaria. Gates wrote a blog post in 2016 highlighting the impact of their philanthropic efforts. Citing a report from The New England Journal of Medicine, he said, "The malaria death rate in sub-Saharan Africa has declined by a stunning 57 percent since 2000."
"With almost 500,000 children still dying of malaria every year, we obviously have a long way to go. But cutting the death rate by more than half is a miracle. It's one of the greatest success stories in the history of global health," he wrote.
The Gates' new mission is fighting the neurodegenerative disease Alzheimer's. Earlier this month, Gates announced that he will invest $100 million in researching its cause and developing an effective treatment.
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