A few of Smithfield Foods' massive pork-processing plants turned into Covid-19 hotspots soon after the virus reached the United States. Employees at the plants typically work in conditions that make it easy for the virus to spread: close quarters, cool temperatures, and constant air circulation. Social distancing measures are hard to implement without slowing down operations.  By mid-April, employees of Smithfield’s Sioux Falls, South Dakota,  plant accounted for half of its county’s reported coronavirus cases. Smithfield, owned by China’s WH Group, was initially reluctant to shut the plant, but gave in after pressure from the Sioux Falls mayor and South Dakota’s governor, who feared endangering workers and spreading the contagion. “It is impossible to keep our grocery stores stocked if our plants are not running,” Smithfield Chief Executive Officer Kenneth Sullivan said in a company statement before the plant went dark. “The closure of this facility, com