RT Journal Article SR Electronic T1 Covid-19: North Dakota and Belgium have let infected health staff work on wards JF BMJ JO BMJ FD British Medical Journal Publishing Group SP m4455 DO 10.1136/bmj.m4455 VO 371 A1 Silberner, Joanne YR 2020 UL http://www.bmj.com/content/371/bmj.m4455.abstract AB