Abstract
Due to its high lethality among older people, the safety of nursing homes has been of central importance during the COVID-19 pandemic. With test procedures and vaccines becoming available at scale, nursing homes might relax prohibitory measures while controlling the spread of infections. By control we mean that each index case infects less than one other person on average. Here, we develop an agent-based epidemiological model for the spread of SARS-CoV-2 calibrated to Austrian nursing homes to identify optimal prevention strategies. We find that the effectiveness of mitigation testing depends critically on test turnover time (time until test result), the detection threshold of tests and mitigation testing frequencies. Under realistic conditions and in absence of vaccinations, we find that mitigation testing of employees only might be sufficient to control outbreaks if tests have low turnover times and detection thresholds. If vaccines that are 60% effective against high viral load and transmission are available, control is achieved if 80% or more of the residents are vaccinated, even without mitigation testing and if residents are allowed to have visitors. Since these results strongly depend on vaccine efficacy against infection, retention of testing infrastructures, regular testing and sequencing of virus genomes is advised to enable early identification of new variants of concern.
Highlights
Nursing homes and other long-term care facilities are the ground zero of the COVID-19 pandemic [1]
We simulate epidemic spread in a nursing home in a range of different scenarios: (i) introduction of index cases through either employees or residents, (ii) different testing technologies used for mitigation testing, (iii) different intervals for the mitigation tests, (iv) different prevalence of vaccinations and (v) combinations of different testing strategies and vaccinations
In the absence of non-pharmaceutical interventions or containment measures and infection with the alpha variant, we find Reff = 2.25 [0; 7] if an employee is the index case and Reff = 2.97 [0; 8] if a resident is the index case
Summary
Nursing homes and other long-term care facilities are the ground zero of the COVID-19 pandemic [1]. A disproportionate number of confirmed deaths has been attributed to nursing home residents. With 923 confirmed cases in nursing homes during this period of time, this results in a case fatality rate of 28%, in line with reported high case fatality rates in the age group above 80 years old [3]. Owing to this extreme severity, in most countries stringent non-pharmaceutical interventions have been suggested for nursing homes, such as bans on visitors, individual movement restrictions and other quarantine policies [4,5]. COVID-19, severely affects the quality of life of all nursing home residents, not just the infected ones [6]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
