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Analysis of COVID-19 outbreaks in 3 long-term care facilities in Graz, Austria
Ines Zollner-Schwetz1, Elisabeth König1, Robert Krause1
1Section of Infectious Diseases and Tropical Medicine, Department of Internal Medicine, Medical University of Graz, Graz, Austria.
Background:
Nursing homes and long-term care facilities (LTCF) caring for elderly and chronically ill residents are at high risk to experience severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) outbreaks. We report an outbreak of coronavirus disease 2019 (COVID-19) in 3 LTCFs of the Geriatric Health Centres of Graz, Austria lasting from March 22 to April 14, 2020.
Aim:
The objectives of our study were: (1) to elucidate contributing factors and transmission pathways of SARS-CoV-2, (2) to analyze symptoms of COVID-19 in the residents and health care workers.
Methods:
We carried out a retrospective outbreak analysis.
Findings:
Thirty-six of /277 residents of 3 LTCFs were infected with SARS-CoV-2. Only a quarter of COVID-19 cases among residents had fever ≥38.1°C and 19% suffered from cough. Six of 36 residents remained asymptomatic. Hospitalization rate was 58% in residents. Overall, 33% (12/36) residents infected with SARS-CoV-2 died. Nineteen of 214 health care workers were tested positive for SARS-CoV-2. Universal rt-PCR testing for SARS-CoV-2 of all residents and health care workers as well as infection control measures contributed to ending the outbreaks.
Conclusions:
Delayed recognition of possible COVID-19 cases due to either mild symptoms or symptoms that were perceived as atypical early in the pandemic contributed to the transmission of SARS-CoV-2 in LTCFs. This emphasizes the importance of low-threshold testing in LTCF residents.
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