I've 'always known' this was a pandemic: Trump

"I didn't feel different. I've always known this is a.. this is a real..this is a pandemic. I've felt it was a pandemic long before it was called a pandemic, all you have to do is look at other countries... No, I always viewed it as very serious," Trump said.

A piece of research that helped convince the British government to impose more stringent measures to contain COVID-19 painted a worst case picture of hundreds of thousands of deaths and a health service overwhelmed with severely sick patients.

The projection study, by a team led by Neil Ferguson, a professor of mathematical biology at Imperial College London, used new data gathered from Italy, where the infectious disease epidemic has surged in recent weeks.

Comparing the potential impact of the COVID-19 disease epidemic with the devastating flu outbreak of 1918, Ferguson's team said that with no mitigating measures at all, the outbreak could have caused more than half a million deaths in Britain and 2.2 million in the United States.

Even with the government's previous plan to control the outbreak - which involved home isolation of suspect cases but did not include restrictions on wider society - could have resulted in 250,000 people dying "and health systems...being overwhelmed many times over," the study said.

With the measures outlined - including extreme social distancing and advice to avoid clubs, pubs and theaters - the epidemic's curve and peak could be flattened, the scientists said.