With two hours left in the trading day, the Toronto stock market was down about 620 points and the Dow Industrials were down about 940 points.
Some analysts say if COVID-19 becomes a global pandemic, the economic impact could be much worse -- with the U-S and other global economies falling into recession.
That's because in some parts of the world, cities are on lockdown, shops and businesses are empty and major tourist sites and events are off limits.
Airlines and cruise operators have experienced some of the worst hits as flight routes are cancelled, along with travel plans.