Half the world's population is exposed to malaria
Microsoft founder Bill Gates has told the BBC that a vaccine for malaria could be just three years away.
Mr Gates is a key campaigner against the disease which kills a million people a year, most of them children.
Since it was formed, his foundation has spent billions of dollars in the fight against malaria.
Just like smallpox, Mr Gates believes the disease can be eradicated. As yet, there is no vaccine, but, Mr Gates says, a breakthrough is near.
"We have a vaccine that's in the last trial phase - called phase three. A partially effective vaccine could even be available within three years, but a [...] fully effective vaccine will take five to 10 years," he told the BBC World Service's World Today programme.
The man believed to be the richest person in the world did have a warning though - he fears developed nations may plunder their foreign aid budgets to pay for the cost of tackling climate change.
Mr Gates says this would be a mistake as aid budgets not only save lives, they also improve people's health and, in turn, that stops population growth - a key reason, he says, for global warming.
"I just want to make sure that that funding doesn't come by reducing the funds for Aids, drugs or vaccines, which, after all, not only do they save lives but its this improved health that actually gets a country to reduce its population growth," he said.
"And, in the long run, for all these environmental issues, having a population that's not growing so rapidly is what will allow us to live on a sustainable basis.
"Climate change is very important, it is an issue money should go to. It just shouldn't come out of health aid budgets."