Mobile PCR-based surveillance for SARS-CoV-2 to reduce visiting restrictions in nursing homes during the COVID-19 pandemic: a pilot study

Abstract

Purpose: Residents in nursing homes for the elderly (NH) are at high risk for death from COVID-19. We investigated whether repeated non-mandatory RT-PCR SARS-CoV-2 surveillance of NH staff and visitors reduces COVID-19 incidence rates in NH residents and allows to reduce visiting restrictions.

Methods: This pilot study at the beginning of the COVID-19 pandemic compared a surveillance approach of regular, twice-weekly voluntary PCR testing of health-care workers (HCW) and visitors in interventional NH (INH) with a setting without regular testing in control NH (CNH). Residents were not tested routinely within this study. Testing was performed in a mobile testing site with same-day result reporting. SARS-CoV-2 incidence among residents in both INH and CNH was the primary endpoint; secondary endpoints being SARS-CoV-2 infection among visitors and HCW in INH.

Results: Two INH and two CNH participated between October and December, 2020. At INH1, 787 tests of HCW and 350 tests of visitors were performed, accounting for 18.1% (n = 1930) of visits. At INH2, 78 tests of HCW and 372 tests of visitors were done, i.e., 30.5% (n = 1220) of visits. At the two INH 23 HCW and three visitors tested positive for SARS-CoV-2. COVID-19 outbreaks occurred among residents in INH1 (identified through study testing) and in CNH1. Utilization of voluntary testing was low.

Conclusion: In a real-world setting without available rapid testing, voluntary RT-PCR SARS-CoV-2 testing of HCW and visitors does not prevent COVID-19 outbreaks in NH. Complete, non-selective testing for these groups should be instituted before visiting restrictions can be reduced.

Trial registration: The study has been registered at ClinicalTrials.gov with the identifier: NCT04933981.

Keywords: COVID-19 pandemic; Nursing home; SARS-CoV-2 transmission; Surveillance; Testing on site.

Conflict of interest statement

JS has received research grants by the Ministry of Education and Research (BMBF) for this study and from Basilea Pharmaceuticals Inc. outside the submitted work and has received travel grants by German Society for Infectious Diseases (DGI e.V.) and Meta-Alexander-Foundation. TK, VD SS, RS, MO SP, UB, CL, and FK have nothing to disclose. UW is employed at Institute of Virology, University of Cologne, and has received funding from the Ministry of Education and Research (BMBF) for this study. GW has received research grants by the Ministry of Education and Research (BMBF) for this study. HR has received research grants by the Ministry of Education and Research (BMBF) for this study. MH has received research grants by the Ministry of Education and Research (BMBF) for this study. GL has received research grants by the Ministry of Education and Research (BMBF) for development of the UHC Corona Webtool. OAC is supported by the German Federal Ministry of Research and Education, is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy—CECAD, EXC 2030—390661388, and has received research grants from, is an advisor to, or received lecture honoraria from Actelion, Allecra Therapeutics, Al-Jazeera Pharmaceuticals, Amplyx, Astellas, Basilea, Biosys, Cidara, Da Volterra, Entasis, F2G, Gilead, Grupo Biotoscana, Immunic, IQVIA, Janssen, Matinas, Medicines Company, MedPace, Melinta Therapeutics, Menarini, Merck/MSD, Mylan, Nabriva, Noxxon, Octapharma, Paratek, Pfizer, PSI, Roche Diagnostics, Scynexis, and Shionogi.

© 2021. The Author(s).

Figures

Fig. 1

Structure and process of mobile SARS-CoV-2 testing at interventional nursing homes. MTS mobile testing site; PCR polymerase chain reaction; UHC University Hospital of Cologne;

Fig. 2

a Timeline of testing and positive results at interventional nursing homes. b SARS-CoV-2 PCR test results and voluntary utilization of testing in INH1. c SARS-CoV-2 PCR test results and voluntary utilization of testing in INH2. CW calendar week; HCW health-care worker; INH interventional nursing home

Fig. 3

Ct values of all positive SARS-CoV-2 test results (including-INH participants and sequentially tested participants). CNH control nursing home; Ct cycle threshold; INH interventional nursing home; RT-PCR reverse-transcriptase polymerase chain reaction; others include SARS-CoV-2 swabs performed by the MTS outside the study population during the observational period