Countries on three continents reported their first cases of the coronavirus on Friday as the world prepared for a pandemic and investors dumped equities in expectation of a global recession.

Share prices were on track for the worst week since the global financial crisis in 2008 as virus-related disruptions to international travel and supply chains fueled fears of recession in the United States and the Euro zone.

Asian stocks followed a plunge on Wall Street, where the benchmark S&P 500 index fell more than 4% on Thursday, extending a rout that has sliced more than 10% off of its closing peak on Feb. 19.

“The coronavirus now looks like a pandemic. Markets can cope even if there is big risk as long as we can see the end of the tunnel,” said Norihiro Fujito, chief investment strategist at Mitsubishi UFJ Morgan Stanley Securities.

“But at the moment, no one can tell how long this will last and how severe it will get.”

Mainland China – where the virus originated late last year – reported 327 new cases, the lowest since Jan. 23, taking its tally to more than 78,800 cases with almost 2,800 deaths.

Four more countries reported first cases, taking the number of countries and territories outside China with infections to 55, with more than 4,200 cases killing about 70 people.

Countries other than China now account for about three-quarters of new infections.

An Italian man who arrived in Nigeria this week was confirmed as the first coronavirus case in Africa’s most populous country. And a person who returned on a flight from Iran became the first in New Zealand.

In eastern Europe, Belarus and Lithuania reported their first cases.

World Health Organization (WHO) Director General Tedros Adhanom Ghebreyesus said all nations should prepare.

“This virus has pandemic potential,” Tedros said in Geneva on Thursday. “This is not a time for fear. This is a time for taking action to prevent infection and save lives now.”

Ratings agency Moody’s said a pandemic – usually taken to mean a disease spreading quickly in different places – would trigger global and U.S. recessions in the first half of the year.

Mongolia, which has yet to confirm a case, placed its president, Battulga Khaltmaa, in quarantine as a precaution after he returned from a trip to China, state media reported.

Scientists say much remains unknown about the virus, which can lead to pneumonia, and a vaccine could take up to 18 months to develop.

A Chinese official called the epidemic the most difficult health crisis in the country’s modern history. Another said some recovered patients had been found to be infectious, suggesting the epidemic may be even harder to eradicate.

In addition to stockpiling medical supplies, governments ordered schools shut and canceled big gatherings to try to halt the flu-like disease known as COVID-19.

U.S. President Donald Trump’s administration was considering invoking special powers to expand production of protective gear.

In Europe, France’s reported cases doubled, Germany warned of an impending epidemic and Greece, a gateway for refugees from the Middle East, announced tighter border controls.

The death toll in Italy, Europe’s worst-hit country, rose to 17 and the number tested positive increased by more than 200 to 655.

Germany has about 45 cases, France about 38 and Spain 23, according to a Reuters count.

Tedros told reporters that Iran, Italy and South Korea were at a “decisive point” in efforts to prevent a wider outbreak.

South Korea has the most cases outside China, and reported 571 new infections on Friday, bringing the total to 2,337. The outbreak, which has killed 13 people in South Korea, has also dented President Moon Jae-in’s popularity, a poll showed.

The head of the WHO’s emergency program, Dr Mike Ryan, said Iran’s outbreak may be worse than realized. It has suffered the most deaths outside China – 26 from 245 reported cases.

U.S. intelligence agencies are monitoring the spread of coronavirus in Iran as well as India, where only a handful of cases of have been reported, sources said.

Japan is scheduled to host the 2020 Olympics in July but Ryan said discussions were being held with organizers about whether to go ahead.

Olympic organizers will decide next week on the ceremonial torch relay. It is due to arrive on March 20 for a 121-day journey past landmarks including Mount Fuji and Hiroshima’s Peace Memorial Park.

As of Friday, confirmed cases in Japan topped 200, with four deaths, excluding more than 700 cases and four more deaths from a quarantined cruise liner, Diamond Princess.

Tokyo Disneyland will close from Saturday to March 15.

Prime Minister Shinzo Abe vowed to take whatever steps necessary to prevent a severe blow to an economy already teetering on the brink of recession.