Bill Gates says the world would need as many as 14 billion doses of a coronavirus vaccine to stop the virus

• The world could need as many as 14 billion doses of COVID-19 vaccines, Bill Gates said on Thursday in a blog post about the race to develop a way to make people immune to the disease.
• "We need to make billions of doses, we need to get them out to every part of the world, and we need all of this to happen as quickly as possible," Gates said.
• Gates said he has his eyes on 8-10 promising candidates, adding that health care workers and people in low-income countries should be first in line once we find one that works.
• While potential vaccines are progressing with historic speed, they're still months or even years away, and the biggest challenge lies ahead in proving whether they are safe and effective in humans.
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Bill Gates believes we may eventually need to produce as many as 14 billion doses of COVID-19 vaccines globally and that we're anywhere from nine months to two years away from making that happen.

In a blog post Thursday, the billionaire Microsoft cofounder and philanthropist outlined what the race for a vaccine could look like, including how long and what it will take to develop one that's both safe and effective, how it will be produced, and who should get it first.

"We need to manufacture and distribute at least seven billion doses of the vaccine," Gates said, "or possibly 14 billion, if it's a multi-dose vaccine." He added that the vaccines should be distributed "as soon as the first batch is ready to go."

After healthcare workers, people in low-income countries should be first in line for a vaccine when it's ready since they're more likely to get sick, Gates argued. Higher rates of underlying health conditions, worse healthcare systems, and high population densities that make social distancing measures harder to implement will allow the disease to spread more easily, he said.

Gates said there will be massive challenges in developing a safe and effective vaccine, as well as producing, storing, and distributing them on such a large scale, and that it will require extensive global cooperation but, said: "I know it'll get done. There's simply no alternative."

"Humankind has never had a more urgent task than creating broad immunity for coronavirus," he said. "We need to make billions of doses, we need to get them out to every part of the world, and we need all of this to happen as quickly as possible.

With more than 3.2 million cases and 233,000 deaths globally, scientists have been working with unprecedented speed to develop a vaccine — a process that has typically taken multiple years — but experts say we're still a long ways from being able to widely vaccinate people.

Dr. Anthony Fauci, the director of the National Institute for Allergies and Infectious Diseases, has similarly said the US is at least 12 to 18 months away from a working vaccine, though experts warn that an expedited timeline could introduce additional risks.

Still, Gates said he's optimistic about a few candidates that are currently being researched and tested.

"As of April 9, there are 115 different COVID-19 vaccine candidates in the development pipeline. I think that eight to ten of those look particularly promising. (Our foundation is going to keep an eye on all the others to see if we missed any that have some positive characteristics, though.)," Gates said.

Gates' philanthropic organization, the Bill & Melinda Gates Foundation, so far has pledged $250 million toward fighting the novel coronavirus, and Gates recently announced that the organization planned to dedicate its full resources to the pandemic.