Salvador Perez became sick with symptoms of COVID-19 in April and spent weeks self-isolating at home in Chicago. When he recovered, his employer asked him to take an antibody test before he’d be allowed to return to work.

Salvador Perez became sick with symptoms of COVID-19 in April and spent weeks self-isolating at home in Chicago. When he recovered, his employer asked him to take an antibody test before he’d be allowed to return to work.