Fig. 1.

a PCR results of respiratory specimens in patients and employees presented on a temporal scale. Patients’ results are grouped according to diagnosis upon admission to the intensive care unit (ICU). Results for every second patient/employee are drawn on a line, b Proportion of virus-positive swabs in patients and employees presented on a temporal scale. CNS Central nervous system, LRTI lower respiratory tract infection, negative negative PCR result, CoV corona virus, INFV A influenza A virus, RSV A respiratory syncytial virus A, other any other of the tested viruses identified, cross indicates time-point at which the last swab before death in patients who died was obtained