It could take up to two years before we get a coronavirus vaccine.

On Thursday night, Bill Gates appeared on Global’s “The Late Show” to talk about the roadmap to a vaccine for the virus that causes COVID-19.

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“There are two ways out: One is if we get miracle therapeutics that are greater than 95 per cent cure rate. We can’t count on that,” Gates explained. “The other is a vaccine that’s highly effective that we get out to the world population. Some of these vaccines — we’ll understand by this summer, we’ll see because they’re going into humans now — we’ll see if they get this strong antibody response.”

He continued, “And then we have to do broad safety testing and get the manufacturing going. So even a year from now, even if everything went perfectly… we could start the manufacturing.”

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Gates added that it’s also possible the timeline will stretch to two years for manufacturing a vaccine but offered some hope.

“Every day when I see the engagement of the vaccine groups, I actually think, Wow, we can surprise people on the upside here,” he said. “I have been saying 18 months but some of these vaccines are ahead of that schedule.”

The billionaire added that through the Bill & Melinda Gates Foundations’ Therapeutics Accelerator he is at work on seven vaccines, with more than 100 vaccines being tested.

“There’s almost too many in a way,” he said.

“The Late Show with Stephen Colbert” airs weeknights at 11:35 p.m. ET/PT on Global.

Questions about COVID-19? Here are some things you need to know:

Health officials caution against all international travel. Returning travellers are asked to self-isolate for 14 days in case they develop symptoms and to prevent spreading the virus to others.

Symptoms can include fever, cough and difficulty breathing — very similar to a cold or flu. Some people can develop a more severe illness. People most at risk of this include older adults and people with severe chronic medical conditions like heart, lung or kidney disease. If you develop symptoms, contact public health authorities.

To prevent the virus from spreading, experts recommend frequent handwashing and coughing into your sleeve. They also recommend minimizing contact with others, staying home as much as possible and maintaining a distance of two metres from other people if you go out.

For full COVID-19 coverage from Global News, click here.