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Hospital-Acquired COVID-19 Infection – The Magnitude of the Problem

15 Pages Posted: 27 Jul 2020



Aims: To quantify prevalence of hospital-acquired COVID-19 infection and to determine whether this is influenced by any patient characteristic

Design: Single-centre retrospective observational cohort study performed in May 2020 Setting General District Hospital in the North West of England

Participants: 239 inpatients who tested positive for COVID-19 infection. Dateof admission ranged from 4th December 2019 to 15th April 2020. Patients were divided into two groups (community vs nosocomial) and assigned to the nosocomial group if the participant developed new-onset in-hospital symptoms (persistent cough, pyrexia T>37.8 C, dyspnoea, desaturation on room air) and had a positive swab after ≥7 days from admission date. Patients discharged for <48hrs after a previous admission of at least 7 days were allocated to the nosocomial group if they had a negative swab during the previous admission.

Results: The rate of nosocomial cases of COVID-19 in this study was 16.2% and the overall mortality for patients was 52.1%. Patients in the nosocomial group had a longer total length of stay (p<0.001) and a longer length of stay after testing positive for COVID-19. There was no significant difference in 30-day mortality between the two groups. The nosocomial group was significantly more frail and had more comorbidities (p value <0.006) compared to the community one. Nosocomial cases were on a “negative” ward 93.8% of the time at the time of symptom onset.

Conclusions: The prevalence of hospital-acquired COVID 19 infection is 16.2%. Patients who were infected with COVID-19 in-hospital had a longer length of stay, but this did not affect mortality. Further studies should be focused on exploring means to reduce in-hospital transmission of COVID-19 and determining risk assessment tools that could stratify patients based on their relative or absolute risk of acquiring COVID-19 in hospital.

Funding Statement: No external funding was received for the study.

Declaration of Interests: The authors declare no competing interests.

Ethics Approval Statement: The authors declare that data was collected in accordance with local governance. Ethical approval was not necessary given the observational nature of the study.

Suggested Citation

Marago, Italo and Minen, Isa, Hospital-Acquired COVID-19 Infection – The Magnitude of the Problem (6/4/2020). Available at SSRN: or

Italo Marago (Contact Author)

NHS Foundation Trust ( email )

London, SE5 8AZ
United Kingdom

Isa Minen


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