Nosocomial COVID-19 on a green ward

Editor – We read the recent article on nosocomial spread of COVID-19 on a stroke/neurology ward with interest.¹ We did a similar observational study in our hospital during the peak of the pandemic. The stroke ward was re-designated as a ‘green ward’, where patients with acute stroke and with non-COVID-19 symptoms were admitted. We wanted to estimate the risk of nosocomial COVID-19 because there was a perception that the risk of COVID-19 was negligible on a green ward.

During the study, we included all patients who stayed for more than 7 days from 15 March 2020 to 30 June 2020. We chose 7 days because, if patients developed COVID-19 after 7 days, we could be certain that they contracted the disease while they were an inpatient rather than delayed diagnosis from admission. Patients were tested for COVID-19 if they developed symptoms, had contact with a symptomatic patient or before transfer to the community. During the study period, staff were advised to use a surgical mask, apron and shield as per public health guidelines.²

Four-hundred and forty-three patients were admitted to the green ward during the study period; 138 patients stayed for more than 7 days, of which 59 tested positive either while as an inpatient or within 7 days of discharge and 12 patients died. During the same period 27 out of 47 healthcare professionals contracted COVID-19.

Despite using the recommended PPE, 42% of patients who stayed more than 7 days contracted COVID-19, of whom 21% died. Fifty-seven per cent of healthcare professionals developed COVID-19, of which, one needed respiratory support and all of them recovered.

Our figures are probably an underestimate due to the low sensitivity of the oropharyngeal swab (60%) and as we did not test all patients and staff, we might have missed a few asymptomatic cases.³

In summary, the risk of nosocomial COVID-19 is high if patients stayed in for more than 7 days and the risk to healthcare workers is extremely high, even on a green ward. This suggest that the recommended protective measures taken to prevent nosocomial COVID-19 were inadequate.