TORONTO -- Canada's main stock index fell for the first time in seven sessions Tuesday on concerns about a virus outbreak in China.

The market experienced a broad-based selloff on worries that the newly identified coronavirus would spread and be as devastating as SARS was in 2002 and 2003.

Anxieties were accentuated after a U.S. citizen who recently returned to Seattle from a trip to central China was diagnosed with the virus. The U.S. is the fifth country to report seeing the illness, following China, Thailand, Japan, and South Korea.

Airlines and leisure companies felt the largest impact. Air Canada's shares dropped 4.5 per cent to $48.84 after hitting a low of $47.68 in trading on the Toronto Stock Exchange.

Market concerns are growing as Chinese New Year approaches on Saturday, said Dominique Barker, portfolio manager at CIBC Asset Management

"Any time you have uncertainty in the market you tend to have an overreaction either way and so right now the uncertainty is related to the coronavirus and so we're just seeing selling," she said in an interview.

Investors could also be using the virus as an excuse to sell, particularly commodities, because markets have been so strong so far this year.

"Our materials analyst said that people are using the coronavirus as an excuse to press the sell button on some of the commodities like copper," Barker said.

Partially offsetting the virus impact on airline shares was Boeing's afternoon announcement that it anticipates regulators won't allow its 737 Max to fly until June or July.

Barker said airline stocks rebounded a bit on the news because a continued tightening of the airplane market allows airlines to keep ticket prices higher.

The S&P/TSX composite index closed down 25.11 points at 17,572.28 after hitting an intraday low of 17,536.31.

In New York, the Dow Jones industrial average was down 152.06 points or the second-largest daily decrease of the year to 29,196.04. The S&P 500 index was down 8.83 points at 3,320.79, while the Nasdaq composite was down 18.13 points at 9,370.81.

The Canadian dollar traded for 76.53 cents US compared with an average of 76.61 cents US on Monday.

Health care led the TSX lower, followed by energy and industrials.

Health care decreased 2.3 per cent as cannabis producers saw their share prices fall with Cronos Group Inc., Aurora Cannabis Inc. and Hexo Corp. each decreasing about five per cent.

Lower crude oil and natural gas prices pushed energy lower with Crescent Point Energy Corp. and Husky Energy Inc. down 5.9 and 5.5 per cent respectively.

The March crude contract was down 20 cents US$58.38 per barrel and the February natural gas contract was down 10.8 cents at US$1.895 per mmBTU.

Consumer discretionary was up a little despite shares of Spin Master Corp. losing 4.9 per cent after the toy maker warned that its 2019 sales were going to be worse than expected because of problems with its distribution system, a softer U.S. market, and fallout from trade disputes.

Materials climbed slightly despite lower metal prices with Kinross Gold Corp. up 3.2 per cent.

The February gold contract was down US$2.40 at US$1,557.90 an ounce and the March copper contract was down 5.2 cents at US$2.79 a pound.