Trump says he is 'confident' that the US will have a coronavirus vaccine by the end of the year. Experts say it could take up to 18 months.

• President Donald Trump said during a Fox News town hall on Sunday night that he was "confident" the US would have a COVID-19 vaccine by the end of the year.
• He said "many" companies currently working to develop a coronavirus vaccine were getting "close" to having a vaccine ready for public use.
• Although companies are moving forward on vaccines at record speed, health experts have estimated that the development and distribution of a vaccine could take anywhere 12 to 18 months.
• And some experts have expressed concern that while at least 115 COVID-19 vaccines are in development, rushing them through the necessary testing and approval channels can be risky.
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President Donald Trump said during a Fox News town hall on Sunday night that he was "confident" the US would have a COVID-19 vaccine by the end of the year, despite estimates from health experts stating that a vaccine could take anywhere from 12 to 18 months before it is readily available to the public.

"We are very confident that we'll have a vaccine by the end of the year," Trump said at the virtual town hall.

"We think we are going to have a vaccine by the end of this year," he said. "We're pushing very hard."

He added that companies like Johnson & Johnson, one of over 70 firms around the world currently working to develop a coronavirus vaccine, was getting "close" to having a vaccine ready for public use.

"Many companies are, I think, close," he said.

Although companies are moving forward on vaccines at record speed, health experts have estimated that the development and distribution of a vaccine could take anywhere 12 to 18 months. Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said in March that the entire process would take "a year, a year and a half, at least."

Of his ambitious projection, Trump said during the town hall: "The doctors would say 'well you shouldn't say that.' But I'll say what I think."

At least 115 COVID-19 vaccines are in development, but rushing them can be risky

Some scientists have expressed concern that even as companies move quickly towards a vaccine and FDA approval processes have been condensed, rushing a vaccine is risky.

According to the Coalition for Epidemic Preparedness Innovations, there are at least 115 COVID-19 vaccines currently in development.

But vaccines for other coronavirus outbreaks, including MERS and SARS, took over 18 months to develop and have yet to be fully approved for use on the public. The vaccine for SARS took 20 months just to be trialed on humans, and the fastest vaccine ever developed, for mumps, took four years.

Professor Chris Whitty, the UK's chief medical officer, said last month that the chances of securing an effective vaccine or treatment for the coronavirus this year are "incredibly small." Swiss pharmaceutical giant Roche said last month that a coronavirus vaccine probably won't be ready before the end of 2021.

Dr. Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine, told Reuters in March that there is a risk that a coronavirus vaccine would actually make the disease worse in people who are infected with COVID-19 after being vaccinated, instead of protecting them from it.

Microsoft billionaire Bill Gates, who recently said his foundation is giving 'total attention' to the coronavirus pandemic, wore in a blog post last week that he considered eight to 10 candidates for a coronavirus vaccine to be promising. He added that a vaccine could take 18 months to develop, though it "could be as little as 9 months or as long as two years," due to the sheer number of approaches being tested by multiple companies at the same time.

"We're doing things that... never happened before," Trump stressed at the town hall. "This country needs a vaccine, and you're gonna have it by the end of the year."