Asian shares took a sudden turn for the worse on Tuesday as mounting concerns about a new strain of coronavirus in China sent a ripple of risk aversion through markets.
Safe-haven bonds and the yen edged higher as investors were reminded of the economic damage done by the SARS virus in 2003, particularly given the threat of contagion as hundreds of millions travel for the Lunar New Year holidays.
"It's an essential enough development that markets will monitor it on the risk radar as, if things turn critical, it could provide a massive blow to the airline industry and a knockout punch to local tourism," said Stephen Innes, Asia Pacific market strategist at AxiCorp.
The mood swing saw MSCI's broadest index of Asia-Pacific shares outside Japan slip 1% after a steady start. Hong Kong, which suffered badly during the SARS outbreak, saw its index fall 2%.
Japan's Nikkei lost 0.8% and Shanghai blue chips 1.5%, with airlines under pressure. The caution spread to E-Mini futures for the S&P 500 which eased 0.4%, while EUROSTOXX 50 futures lost 0.3%.
Investors had already been guarded after the International Monetary Fund trimmed its global growth forecasts, mostly due to a surprisingly sharp slowdown in India and other emerging markets.
There had been some relief as US President Donald Trump and French President Emmanuel Macron seemed to have struck a truce over a proposed digital tax.
The two agreed to hold off on a potential tariffs war until the end of the year, a French diplomatic source said.
Trump is due to deliver a speech at the World Economic Forum in Davos later on Tuesday, and trade and tariffs could be on the agenda.
In a tweet late on Monday, Trump said he would be bringing "additional Hundreds of Billions of Dollars back to the United States of America! We are now NUMBER ONE in the Universe, by FAR!!"
All Steady at Boj
The Bank of Japan cited lessened trade risks when nudging up forecasts for economic growth after holding a policy meeting on Tuesday.
As widely expected, the BOJ maintained its short-term interest rate target at -0.1% and a pledge to guide 10-year government bond yields around 0%, by a 7-2 vote.
Japan's yen picked up a bid on the safe-haven move and the dollar dipped to 109.92 from an early 110.17. It also gained on the euro, leaving the single currency flat on the dollar at $1.1092.
Against a basket of currencies, the dollar was steady at 97.599, just off a four-week high of 97.729.
The Australia dollar took a knock from the flu worries since it attracts large numbers of Chinese tourists, who tend to be big spenders over the Lunar New Year holidays.
Australia said it would step up screening of some flights from Wuhan.
The outbreak was particularly badly timed as the tourism industry has been mauled already by bushfires sweeping the country.
Spot gold edged up to $1,566.71 per ounce, and back toward a seven-year peak of $1,610.90 reached last week.
Oil prices hesitated, having earlier gained on the risk of supply disruption in Libya.
Brent crude futures eased 31 cents to $64.89 a barrel, while US crude fell 5 cents to $58.49.