In a waiting room overlooking a road that cuts through some of the D.C. neighborhoods hardest hit by the coronavirus (COVID-19) outbreak, a grandmother sat in a chair six feet from her granddaughter as they waited for their names to be called.

Sharron Carroll, 57, bounced her leg nervously as she thought about the test that lay ahead. She has seen the pictures — a long swab stuck up patients’ noses, one nostril at a time.