Why will it take so long to make a coronavirus vaccine that can prevent COVID-19?

Nothing can stop a global outbreak in its tracks better than a vaccine. Unfortunately, creating a vaccine capable of preventing the coronavirus that causes COVID-19 will probably take at least a year to 18 months, health officials say.

"That is the time frame," Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, told the House Oversight and Reform Committee this week. Anyone who says they can do it faster "will be cutting corners that would be detrimental."

While there are about 10 vaccine candidates in the works - and at least one of them could begin clinical trials in April - it would still take about three more months to conduct the first stage of human testing and another eight months or so to complete the next stage of the trial process, he added.

New vaccines require copious research and time-consuming testing that can cost hundreds of millions of dollars. There's no guarantee of success, but even if everything goes well, the final product might not hit the market until after an outbreak has subsided.

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