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US stocks have already notched their worst week since the global financial crisis. The pain is deepening on Friday.

What’s happening: Global stocks have entered their seventh straight trading day in the red as investors worry that the coronavirus outbreak is evolving into a pandemic with serious consequences for global economic growth and corporate earnings, shocking them out of their complacency.

On Thursday, the S&P 500 entered a correction, sliding more than 10% from its recent peak. It marked the fastest market correction on record, according to Deutsche Bank’s Torsten Slok.

“The speed of the decline in the stock market is historic,” Slok told me. “The market is waiting for a circuit breaker which can reverse the current negative narrative.”

That looks unlikely to come this week. Following a deepening rout in Europe and Asia, the Dow opened down 750 points, or 2.9%. The S&P 500 opened down 2.8%.

The index lost 10.8% in the past four trading sessions alone. Even before Friday, it was heading for the steepest weekly loss since the global financial crisis.

Driving the sell-off are fears that the outbreak will not be contained any time soon, and that the damage will be felt way beyond China — the world’s second biggest economy. A stream of warnings from companies in recent days have also put investors on edge. IAG, the owner of British Airways, and Chinese search giant Weibo became the latest to sound the alarm on Friday.

Big picture: Wall Street strategists had been warningt that stock prices were too high given the risks of the virus. And US stocks are still enjoying the longest bull market in history. But right now, fear is driving traders. The CNN Business Fear & Greed Index is now showing “extreme fear.” It started the year in “extreme greed” territory.

“The US economy is not immune,” Bank of America economists Aditya Bhave and Ethan Harris told clients on Friday. “Broken global supply chains will deplete inventories and delay investment.”

The biggest concern, they cautioned, is that Americans will stop spending, sparking an “adverse feedback loop” with markets. In that case, the Federal Reserve could be forced to act “swiftly and aggressively,” they said.

Companies ban business travel as outbreak escalates

Big European companies have started to ban or restrict business travel for hundreds of thousands of employees as the coronavirus outbreak accelerates, my CNN Business colleague Hanna Ziady reports.

Nestlé (NSRGF), the world’s largest food company, said Thursday it has asked all 291,000 of its employees not to travel internationally for business until the middle of March. “Domestic travel should be replaced by alternative methods of communication where possible,” a company spokesperson added.

A spokesperson for L’Oreal said all business trips have been suspended until the end of March “as a precautionary measure.”

And consumer goods giant Unilever said it has been restricting travel to and from northern Italy and other affected countries. Beyond that the guidance is “business-critical travel only,” a company spokesperson said.

Why it matters: The restrictions are piling pressure on airlines and the broader travel industry, which faces a monthly hit of more than $46 billion from the coronavirus, according to the Global Business Travel Association.

Major European airlines are already taking steps to cut costs. Lufthansa and Air France-KLM announced this week that they are offering employees unpaid leave and pausing or reducing hiring. Shares of both companies are down more than 20% in the past week.

The Geneva Motor Show has been called off

Next week’s Geneva Motor Show has been canceled because of coronavirus fears, striking a marquee event from the global auto industry’s calendar as it braces for a third year of recession.

Switzerland’s Federal Office of Public Health on Friday said that gatherings of more than 1,000 people had been banned through at least March 15 in a bid to restrict the spread of the virus, my CNN Business colleagues Charles Riley and Eoin McSweeney report.

“We regret this situation, but the health of all participants is our and our exhibitors’ top priority,” conference organizers said in a statement.

The list of canceled events that usually are a key part of the business calendar continues to grow. Facebook also said this week that it was calling off F8, its biggest annual event. Mobile World Congress was canceled earlier this month.

Up next

US personal income and spending data for January arrives at 8:30 a.m. ET. The final reading the University of Michigan consumer sentiment survey for February follows at 10 a.m. ET.

Coming next week: Will OPEC step in amid a collapse in global oil prices? The group meets in Vienna to discuss next steps.