factory activities U.S. Business Activity Slows in January with Omicron Surge Tuesday, 25 January 2022: U.S. business activity slows in January amid Omicron wave, says a IHS Markit survey. Reports says U.S. business activity grew at its slowest pace in 18 months in January. The slowdown was because of a winter surge in COVID-19 infections worsening worker shortages at