Which event caused the sharp global stock-market fall in February and March 2020?

The COVID-19 pandemic caused the sharp global stock-market fall of February and March 2020.

As the novel coronavirus spread internationally, governments introduced travel restrictions, business closures, quarantines, and other measures that sharply reduced economic activity. Investors rapidly revised expectations for corporate earnings, employment, trade, and energy demand. The resulting selling affected major markets around the world.

The S&P 500 entered a bear market on March 12, 2020, and reached its pandemic-era low on March 23. The Federal Reserve cut interest rates to near zero and launched extensive lending and asset-purchase programs, while governments introduced large fiscal-support measures. The crash was unusually rapid, but markets later recovered as policy support expanded and vaccine development progressed. It is distinct from the 2008 crash, which originated in financial-sector and housing-market problems rather than a global infectious-disease emergency.