Updated March 13, 2020 03:25:55

An early plunge on Wall Street has triggered a trading halt as global markets continue to react to the coronavirus crisis.

The S&P 500 dropped about 7 per cent within minutes of Thursday's open, steep enough to trigger an automatic halt to trading on the New York Stock Exchange.

It is the second automatic trading halt this week, a mechanism which had not previously been used since 1997.

All three main indexes have now fallen over 24 per cent from record highs hit in February, the US now officially in a bear market.

At 9:54am (US Eastern time) the Dow Jones Industrial Average was down 2,075.96 points, or 8.81 per cent, at 21,477.26, the S&P 500 was down 223.81 points, or 8.16 per cent, at 2,517.57 and the Nasdaq Composite was down 635.56 points, or 7.99 per cent, at 7,316.49.

European markets are down 10 per cent, even after the European Central Bank announced more stimulus measures.

Breaking down the latest news and research to understand how the world is living through an epidemic, this is the ABC's Coronacast.

President Donald Trump's shock move to halt travel from Europe rattled investors already alarmed about a global recession on the back of a coronavirus pandemic.

He hinted at plans for tax cuts and other economic relief, but has yet to unveil details. Policy-makers have resisted his proposal for a cut to payroll taxes.

Michael McCarthy of CMC Markets said the market judgement on Mr Trump's announcement was "too little, too late".

"While travel restrictions on people coming from Europe are good from a health point of view, from the point of view of the economy, it's very, very bad news," he said.

Investors are also looking ahead to the European Central Bank's policy meeting, expecting it to cut interest rates and offer more monetary stimulus, though experts say it is governments that must act to help the economy.

The recent decline has been one of Wall Street's swiftest retreats of this magnitude.

The fastest the S&P 500 has ever fallen from a record into a bear market was over 55 days in 1987.

Vicious market swings are becoming routine as investors rush to sell amid uncertainty about how badly the outbreak will hit the economy.

AP/Reuters

Topics: infectious-diseases-other, respiratory-diseases, international-financial-crisis, international-financial-institutions, scott-morrison, business-economics-and-finance, government-and-politics, consumer-finance, economic-trends, united-states

First posted March 13, 2020 01:07:34