By Steven Russolillo and Avantika Chilkoti 

U.S. stock indexes followed Asia and Europe lower amid concerns about the rapid spread of a potentially deadly pneumonialike virus that originated in central China .

The Dow Jones Industrial Average fell 50 points, or 0.1%, to 29296 shortly after the opening bell. The S&P 500 declined 0.2% and the Nasdaq Composite also dropped 0.2%.

Elsewhere, the pan-continental Stoxx Europe 600 index fell 0.3%. The Shanghai Composite closed 1.4% lower in its biggest drop in over two months, while the Chinese yuan lost 0.6% against the dollar in offshore trading.

Shares of U.S. airlines fell with Delta Air Lines losing 1.3% and American Airlines Group dropping 2.5% on worries that the virus could hurt the tourism industry. United Airlines Holdings retreated 2.4%.

The newly identified virus has spread between humans, a leading Chinese health official said, fueling concerns that the disease could quickly be transmitted across Asia as millions of Chinese travel for the annual Lunar New Year holiday. The virus has already claimed six lives as the number of confirmed cases tripled on Monday. A similar coronavirus led to the outbreak of severe acute respiratory syndrome, or SARS, in late 2002 in southern China, killing 774 people.

"The economic consequences could be extremely concerning," said Rajiv Biswas, chief economist for the Asia-Pacific region at IHS Markit. "China's international tourism has boomed, so the risks of a global SARS-like virus epidemic spreading globally have become even more severe."

Brent crude, the global benchmark for oil, dropped 0.9% to $64.59 a barrel as the International Monetary Fund's decision to trim global growth forecasts led to speculation that demand for oil could drop. Concerns about supply disruptions in Libya from earlier in the week also abated.

Later in the day, a string of U.S. companies are scheduled to report earnings including Netflix and International Business Machines Corp.

Shares of airlines, cinemas and restaurant operators dropped in China as investors tried to decipher the impact of the disease in the region. Japan's Nikkei 225 benchmark also fell 0.9%.

Hong Kong's Hang Seng benchmark was the worst performer among major Asian benchmarks, closing down 2.8% in its biggest decline in over five months. Adding to the gloom in Hong Kong, Moody's Investors Service downgraded the city's credit rating. The ratings firm blamed the government for failing to properly deal with seven months of social unrest, which has driven the economy into recession.

Apart from the Chinese yuan, other Asian currencies also fell against the U.S. dollar on fears that tourism and Asian economies could be adversely impacted if there is a widespread outbreak of the virus.

"Global asset markets have been pricing in this blue-sky scenario: there wasn't a cloud in the sky," said Cliff Tan, East Asian head of global markets research at Japanese bank MUFG. "Now we have a cloud."

In Europe, International Consolidated Airlines Group, which owns British Airways, declined about 3.6%. Stocks of luxury retailers -- led by France's Kering SA, owner of the Gucci and Yves Saint Laurent brands, and Switzerland's Cie. Financière Richemont SA -- also retreated.

Major market moves among other European equities were largely driven by corporate results. Hugo Boss ticked up after the German fashion house's sales in the fourth quarter exceeded analysts' expectations, buoyed by momentum in Europe and China. EasyJet gained after the budget airline posted higher-than-expected revenue for the fiscal first quarter and boosted its forecast for revenue per seat for the first half of the year.

Among the biggest losers was UBS Group, which retreated over 5% after the Swiss banking giant missed its key 2019 targets and lowered its guidance.

Within commodities, copper prices dropped, putting the metal on track for the biggest fall in four months, as investors weighed the impact of the virus on China's economy and the typical slowdown in buying ahead of Lunar New Year holidays.

-- Caitlin Ostroff contributed to this article.

Write to Steven Russolillo at steven.russolillo@wsj.com and Avantika Chilkoti at Avantika.Chilkoti@wsj.com

(END) Dow Jones Newswires

January 21, 2020 09:55 ET (14:55 GMT)

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