London’s FTSE 100 share index fell more than 3% and there were similar declines in other European markets.
In the US, upbeat data on hiring and unemployment failed to buoy investors.
The Dow Jones Industrial Average closed almost 1% lower, while the Nasdaq slumped 1.8% and S&P 500 ended down 1.7%.
The monthly report from the US Labor Department found US employers added 273,000 jobs in February – significantly beating expectations – while the jobless rate fell back to near a 50-year low of 3.5%.
The report also revised up estimates of job gains in January and December, finding 85,000 more than previously understood.
The surveys, however, reflect data collected before the outbreak intensified. In recent weeks, global travel has plunged, while work, school and shopping has been disrupted in many countries.
Despite the strong data, markets were focused on the impact of the virus. “Today’s jobs report is old news,” said Sarah House, senior economist at Wells Fargo.
The economic strength signalled in the report is a “little like the saying, the car was in fine condition before being involved in a collision”, said Mark Hamrick, senior economic analyst for Bankrate.com.
“The new reality, amid tremendous uncertainty, is the world has experienced a seismic shift,” he said.
Earlier on Friday, markets in Asia had seen big falls, with Japan’s Nikkei share index dropping by 2.7%.
The 3.6% drop in the FTSE 100 wiped out the gains seen earlier this week on the index.
Shares in travel companies again saw some of the steepest falls.
Banks also took a hit, as investors anticipate that interest rates might be cut in order to make borrowing cheaper for companies and consumers to keep the economy buoyant.
Energy firms were under pressure as well, after the collapse of a proposal by major oil producers to keep oil supply in check sent oil prices tumbling more than 8%.
“The markets didn’t even bother with the pretence of a calm start on Friday, bringing another rough week to a close,” said Connor Campbell, analyst at financial spread better Spreadex.
“The week’s various central bank rate cuts only served to reinforce the seriousness of the situation.”
Earlier this week, the Federal Reserve, the US’s central bank, cut its benchmark interest rate by 0.5 percentage points to a range of 1% to 1.25% in an attempt to ease investor concerns.
Many analysts predict it will cut rates again – perhaps as soon as its meeting this month.
As traders seek less risky investments, they are turning to government bonds, sending prices higher.
The bond market – which is many times larger than the stock market – includes tradable loans to governments and businesses. Yields – how much investors will recoup in interest from the loans – drop as the price of the loan rises.
Benchmark 10-year UK government debt now only offers a 0.24% return – a record low. In the US, the yield on a 10-year Treasury also fell to a record low, falling below 0.7%.
“With the 10-year Treasury yield slumping to a new record low and stock markets under pressure again today, it is questionable whether the Fed can wait until its scheduled meeting mid-month to deliver the next rate cut,” said Paul Ashworth, chief US economist at Capital Economics.