The blame game hit global markets on Monday (May 4).
Stocks struggled for traction as a U.S.-China spat over the origin of Covid-19 put the brakes on any optimism as countries around the world ease restrictions.
In thinned trade, with China and Japan on holiday, MSCI's broadest index of Asia-Pacific shares outside Japan fell 2.5%, pulled down by Hong Kong.
The Hang Seng returned from a two-session holiday with its biggest drop in six weeks.
European stocks also tumbled, as investors returned from a May Day break.
The pan-European STOXX 600 fell 2.5% in a downbeat start to the month after the index recorded a 6% gain in April.
Oil & gas, automakers, banking and technology were the biggest drags.
Germany's Thyssenkrupp slumped 13% after a report that the crisis could cause a new financial squeeze despite the sale of its elevator business.
Donald Trump and U.S. Secretary of State Mike Pompeo have made fresh efforts to pin blame for the pandemic on China.
The latest salvo came from Pompeo on Sunday (May 3), when he said there was "a significant amount of evidence" that the virus emerged from a laboratory in the city of Wuhan.
An increase in tension between Washington and Beijing comes as the world economy gets battered.
Asia's factory activity was ravaged in April, business surveys showed on Monday.
And in the U.S., manufacturing plunged to an 11-year low last month.
None of this plays out well for dwindling oil prices.
U.S. crude snapped three sessions of gains with a 6% drop.