Asian stock markets plunged further on Friday on spreading virus fears, deepening a global rout after Wall Street endured its biggest one-day drop in nine years.

The Tokyo and Shanghai benchmarks sank by an unusually wide margin of 3.7 per cent. Seoul and Sydney dropped by more than 3pc and Hong Kong lost 2.5pc. Oil prices slumped on expectations industrial activity and demand might contract.

Investors had been confident the disease that emerged in China in December might be under control. But outbreaks in Italy, South Korea and Iran have fueled fears the virus is turning into a global threat that might derail trade and industry.

Anxiety intensified on Thursday when the United States reported its first virus case in someone who hadn't travelled abroad or been in contact with anyone who had.

On Wall Street, the benchmark S&P 500 index is down 12pc from its all-time high a week ago.

A growing list of major companies are issuing profit warnings and say factory shutdowns in China are disrupting supply chains. They say travel bans and other anti-disease measures also are hurting sales in China, a major consumer market.

Virus fears "have become full-blown across the globe as cases outside China climb," Chang Wei Liang and Eugene Leow of DBS said in a report.

Tokyo's Nikkei 225 tumbled to 21,142.96 while the Shanghai Composite Index lost 3.7pc to 2,880.30. Hong Kong's Hang Seng lost 2.5pc to 26,097.90.

The Kospi in Seoul fell 3.3pc to 1,987.01 and Sydney's S&P-ASX 200 sank 3.3pc to 6,441.20. India's Sensex was trading 2.8pc lower at 38,635.17.

New Zealand and Southeast Asian markets also retreated.

Markets in China and Hong Kong had been doing relatively well in recent weeks despite anxiety over the virus. On the mainland, authorities flooded markets with credit to shore up prices after trading resumed following an extended Lunar New Year holiday.

Chinese investor sentiment also has been buoyed by promises of lower interest rates, tax breaks and other to help revive manufacturing and other industries.

However than confidence was shaken as the S&P 500 fell 4.4pc on Thursday to 2,978.76.

The Dow Jones Industrial Average shed 1,190.95 points, its largest one-day point drop in history, bringing its loss for the week to 3,225.77 points, or 11.1pc. To put that in perspective, the Dow's 508-point loss on Oct 19, 1987, was equal to 22.6pc.

"It is a race to the bottom for US indices," Jingyi Pan of IG said in a report. "It may still be too early to call a bottom given the uncertainty around the matter of the coronavirus impact."

Investors came into 2020 feeling confident the Federal Reserve would keep interest rates at low levels and the US-China trade war posed less of a threat to company profits after the two sides signed a truce in January.

The S&P 500's decline puts the index into what market watches call a correction.

Some analysts have said that was long overdue in a record-setting bull market, though Mizuho Bank noted it was "the fastest correction since the Great Depression" in the 1930s.

US bond prices soared as investors fled to safe investments. The yield on the benchmark 10-year Treasury note fell as low as 1.20pc, a record low. When yields fall, it's a sign that investors are feeling less confident about the strength of the economy.

China shut down much of its economy to stem the spread of the infection.

Most access to the city of Wuhan, a manufacturing hub at the centre of the outbreak, was suspended Jan 23.

The Lunar New Year holiday was extended to keep factories and offices closed. The government told the public to stay home.

Authorities are shifting to trying to reopen factories and other businesses in areas with low disease risk but travel controls still are in effect in many areas.

Elsewhere, governments are tightening anti-disease controls as new cases mount.

Japan may close schools nationwide. Saudi Arabia banned foreign pilgrims from entering the kingdom to visit Islams holiest sites. Italy has become the centre of the outbreak in Europe, with the spread threatening the financial and industrial centres of that nation.

Goldman Sachs on Thursday said earnings for companies in the S&P 500 index might not grow at all this year, after predicting earlier that they would grow 5.5pc.

Stocks are already trading at high levels relative to their earnings, raising the risk. Before the virus worries exploded, investors had been pushing stocks higher on expectations that strong profit growth was set to resume for companies after declining for most of 2019.

The S&P 500 recently traded at its most expensive level, relative to its expected earnings per share, since the dot-com bubble was deflating in 2002, according to FactSet. If profit growth doesn't ramp up this year, that makes a highly-priced stock market even more vulnerable.

Traders are increasingly certain Federal Reserve will be forced to cut interest rates to protect the economy.

They are pricing in a 96pc probability of a cut at the Feds next meeting in March. Just a day before, they were calling for only a 33pc chance, according to CME Group.

The market's sharp drop this week partly reflects increasing fears among many economists that the US and global economies could take a bigger hit from the coronavirus than previously thought. It also likely will weaken Americans' confidence in the economy, analysts say, possibly depressing consumer spending.

In energy markets, benchmark US crude fell $1.35 to $45.74 per barrel in electronic trading on the New York Mercantile Exchange. The contract lost $1.64 on Thursday to settle at $47.09. Brent crude oil, used to price international oils, sank $1.39 to $50.34 per barrel in London. It declined $1.25 the previous session to $52.18 a barrel.

The dollar declined to 108.85 yen from Thursday's 109.58 yen. The euro fell to $1.0994 from $1.0998.