AP Exclusive: Coronavirus vaccine test opens with 1st doses

A syringe containing the first shot given in the first-stage safety study clinical trial of a potential vaccine for COVID-19, the disease caused by the new coronavirus, rests on a table, Monday, March 16, 2020, at the Kaiser Permanente Washington Health Research Institute in Seattle. (AP Photo/Ted S. Warren)

Pharmacist Michael Witte, left, gives Rebecca Sirull, right, a shot in the first-stage safety study clinical trial of a potential vaccine for COVID-19, the disease caused by the new coronavirus, Monday, March 16, 2020, at the Kaiser Permanente Washington Health Research Institute in Seattle. Sirull is the third patient to receive the shot in the study. (AP Photo/Ted S. Warren)

SEATTLE — U.S. researchers gave the first shots in a first test of an experimental coronavirus vaccine Monday, leading off a worldwide hunt for protection even as the pandemic surges.