Nosocomial Infection Outbreak due to SARS-COV-2 in a Hospital Unit of Particularly Vulnerable Patients

[Abstract] Objectives: To report a COVID-19 outbreak among workers and inpatients at a medical ward for especially vulnerable patients. Methods: Descriptive study of a nosocomial COVID-19 outbreak registered in March-April 2020 at medical ward of onco-hematological patients in an Spanish hospital. Confirmed cases were hospitalized patients, healthcare and non-healthcare workers who tested positive by PCR on a nasopharyngeal swab. Results: Twenty-two COVID-19 cases (12 workers and 10 inpatients) were laboratory-confirmed. Initial cases were a healthcare provider and a visitor who tested positive. The median patients age was 73 years (range 62-88). The main reason of admission was haematological in 8 patients and oncologic in 2. All patients followed an immunosuppressive treatment, 5/10 with high-flow oxygen nebulizations. Five patients presented a moderate/serious evolution, and 5 patients died. The mean workers age was 42.1±10.9. One healthworker required Intensive Care Unit admission, and all of them recovered completely. Conclusions: In the hospital setting, close patients surveillance for SARS-CoV-2 is essential, especially in immunosuppressed patients. Replacing nebulizations or high-flow oxygen therapies, when other equivalent options were available, to reduce dispersion, and controlling ventilation ducts, together with hygiene measures and an active follow-up on inpatients, visitors and workers appear to be important in preventing nosocomial outbreaks