The world’s richest nations poured unprecedented aid into the global economy on Thursday as coronavirus cases ballooned in the new epicentre Europe, with the number of deaths in Italy outstripping those in mainland China, where the virus originated.

With over 242,000 infections and nearly 10,000 deaths, the epidemic has stunned the world and drawn comparisons with painful periods such as World War Two, the 2008 financial crisis and the 1918 Spanish flu.

U.N. chief Antonio Guterres warned that a global recession, “perhaps of record dimensions”, was a near certainty.

“This is a moment that demands coordinated, decisive, and innovative policy action from the world’s leading economies,” Guterres told reporters via a video conference. “We are in an unprecedented situation and the normal rules no longer apply.”

Tourism and airlines have been particularly battered, as the world’s citizens hunker down to minimize contact and curb the spread of the highly contagious COVID-19 respiratory illness. But few sectors have been spared by a crisis threatening a lengthy global recession.

The United States is urging Americans not to travel abroad at all and could announce restrictions at the U.S.-Mexican border on Friday. They would be similar to the closure of the U.S.-Canada border to non-essential traffic.

Markets have suffered routs unseen since the 2008 financial debacle, with investors rushing to the U.S. dollar as a safe haven. Wall Street tried to bounce back on Thursday. The benchmark S&P 500 closed up 0.5%, still around 30% off highs reached last month. U.S. oil prices posted their largest one-day gain ever, rising 25%.

Policymakers in the United States, Europe and Asia have slashed interest rates and opened liquidity taps to try to stabilise economies hit by quarantined consumers, broken supply chains, disrupted transport and paralysed businesses.

Supermarkets in many countries were besieged with shoppers stocking up on food staples and hygiene products. Some rationed sales and fixed special hours for the elderly, who are particularly vulnerable to severe illness.

With some economists fearing prolonged pain akin to the 1930s Great Depression and others anticipating a bounceback, gloomy data and forecasts abounded.