Hostname: page-component-7c8c6479df-ph5wq Total loading time: 0 Render date: 2024-03-28T20:48:42.110Z Has data issue: false hasContentIssue false

Rostered routine testing for severe acute respiratory coronavirus virus 2 (SARS-CoV-2) infection among healthcare personnel—Is there a role in a tertiary-care hospital with enhanced infection prevention and control measures and robust sickness-surveillance systems?

Published online by Cambridge University Press:  02 June 2021

Angela Chow*
Affiliation:
Department of Clinical Epidemiology, Office of Clinical Epidemiology, Analytics, and Knowledge, Tan Tock Seng Hospital, Singapore Saw Swee Hock School of Public Health, National University of Singapore Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
Huiling Guo
Affiliation:
Department of Clinical Epidemiology, Office of Clinical Epidemiology, Analytics, and Knowledge, Tan Tock Seng Hospital, Singapore
Win Mar Kyaw
Affiliation:
Department of Clinical Epidemiology, Office of Clinical Epidemiology, Analytics, and Knowledge, Tan Tock Seng Hospital, Singapore
Anthony Lianjie Li
Affiliation:
Department of Clinical Epidemiology, Office of Clinical Epidemiology, Analytics, and Knowledge, Tan Tock Seng Hospital, Singapore
Rachel Hui Fen Lim
Affiliation:
Department of Clinical Epidemiology, Office of Clinical Epidemiology, Analytics, and Knowledge, Tan Tock Seng Hospital, Singapore
Brenda Ang
Affiliation:
Department of Infectious Disease, Tan Tock Seng Hospital, Singapore Department of Infection Prevention and Control, Tan Tock Seng Hospital, Singapore
*
Author for correspondence: Angela Chow, E-mail: angela_chow@ttsh.com.sg
Rights & Permissions [Opens in a new window]

Abstract

Type
Letter to the Editor
Copyright
© The Author(s), 2021. Published by Cambridge University Press on behalf of The Society for Healthcare Epidemiology of America

To the Editor—Active surveillance allows (1) early identification and isolation of individuals infected with severe acute respiratory coronavirus virus 2 (SARS-CoV-2), (2) tracing and quarantining close contacts, and (3) prevention of further transmission. Simulation studies suggest that rostered routine testing (RRT) for asymptomatic healthcare personnel (HCP) amid ongoing community transmission can substantially reduce the risk of coronavirus disease 2019 (COVID-19) outbreaks in hospitals. Reference Chin, Huynh and Chapman1

With the low prevalence of SARS-CoV-2 in asymptomatic HCP of 0.1%–0.4%, the benefits of RRT for asymptomatic HCP in hospitals with good infection prevention and control practices and robust staff acute respiratory illness (ARI) surveillance systems remain questionable. Reference Shenoy and Weber2Reference Lim, Htun and Wang7 However, with the emergence of more highly transmissible SARS-CoV-2 variant strains and institutional outbreaks caused by them, Reference Sim and Kok8 Singapore’s Ministry of Health has implemented RRT for HCP working in acute-care hospitals.

On April 28, 2021, a nurse working in a general ward in Tan Tock Seng Hospital (TTSH) was confirmed with COVID-19 after seeking medical attention for ARI. A patient receiving care in the same ward was also confirmed with COVID-19 later that day. By May 22, 47 COVID-19 cases had been linked to the ward cluster caused by the B.1.617.2 variant strain. We describe the experience at TTSH in detecting COVID-19 in (1) HCP who were close contacts of COVID-19 cases linked to the cluster, (2) HCP who had been to the affected ward, and (3) asymptomatic HCP screened as part of outbreak management.

The TTSH is a 1,600-bed acute tertiary-care hospital with mostly multibed rooms with 4–6 patients each. The affected location was a multidisciplinary general ward without special isolation facilities. Aside from nurses and housekeepers who were ward-based, other HCP including physicians, surgeons, pharmacists, therapists, phlebotomists, and porters moved between wards.

Upon detection of the cluster on April 28, 2021, the affected ward was locked down and contact tracing was initiated. HCP close contacts were defined as those who had interacted with a confirmed COVID-19 patient or HCP for a cumulative duration of ≥15 minutes within a distance of 2 m, or ward-based HCP. Close contacts were placed on quarantine and were screened for SARS-CoV-2 infection via polymerase chain reaction (PCR) test on entry to quarantine and at 7, 14, and 21 days from the date of last exposure to the confirmed case or to the ward. Furthermore, HCP who had visited the affected ward between April 20 and 28, 2021, for a cumulative duration of ≥15 minutes were also identified, placed on quarantine, and screened for SARS-CoV-2 infection on entry to quarantine and at 7, 14, and 21 days from the date of last exposure to the affected ward. The first patient identified with COVID-19 was admitted to the ward on April 20, and the ward was locked down on April 28. Additionally, all asymptomatic HCP working in the hospital underwent weekly SARS-CoV-2 PCR testing until the affected ward reopened on May 22.

Among 416 HCP close contacts who were placed under quarantine, 1 HCP was detected with SARS-CoV-2 infection via quarantine on-entry test 1 day prior to ARI symptom onset, and 2 were detected when they developed ARI symptoms within first 4 days of quarantine (Table 1). Among the 634 HCP who had visited the affected ward for ≥15 minutes, 1 HCP was positive 2 days prior to symptom onset.

Table 1. Categories of Healthcare Personnel (HCP) Screened for and Detected With SARS-CoV-2 Infection, April 28–May 22, 2021

a Had an interaction with a confirmed COVID-19 patient or HCP for a cumulative total duration of ≥15 min within a distance of 2 m, or were ward-based HCP.

b Visited the affected ward between April 20 and 28, 2021, for a cumulative total duration of ≥15 min.

Of 11,004 asymptomatic staff who had undergone 2 rounds of weekly SARS-CoV-2 PCR testing, none was confirmed with COVID-19. However, 10 were identified to have equivocal results, with high cycle threshold values ranging from 37.42 to 43.30. For these HCP with equivocal results, subsequent 2 swabs taken 24 hours apart yielded negative results by the hospital’s laboratory and the national reference laboratory. All except 1 HCP had nonreactive serology test results; that HCP was a returned traveler from India who was diagnosed with COVID-19 on arrival to Singapore in March 2021. Each HCP with an equivocal test result was placed on leave of absence (LOA) and was advised to self-isolate at home except for returning to the hospital for tests. Coworkers identified to be close contacts of the HCP were also placed on LOA until the repeated tests returned negative. An average of 7 HCP close contacts (maximum, 18) per HCP with equivocal test results were placed on LOA from work for a mean duration of 3.5 days (maximum, 5).

Although the screening of presymptomatic and symptomatic HCP close contacts and HCP who had visited the affected ward yielded a SARS-CoV-2 detection rate of 0.7% and 0.2% respectively, hospital-wide weekly screening of other asymptomatic HCP did not detect any SARS-CoV-2 infections. Instead, the hospital-wide screening resulted in a loss of productivity of 292 HCP-workdays, with a mean of 3.5 work days lost per HCP placed on LOA. For the HCP (a cook in the hospital) with the greatest number of HCP close contacts (n = 18) placed on LOA, response to the equivocal test result caused a reduction in food choices and compromised the nutritional services available to patients.

Even in the wake of a ward cluster due to a highly transmissible SARS-CoV-2 variant strain, the extensive hospital-wide testing of asymptomatic HCP did not uncover any covert infections. With the hospital’s robust infection prevention and control measures and HCP ARI surveillance system, the implementation of RRT may yield limited benefits and paradoxically exacerbate strained manpower and laboratory resources that could be conserved to manage community SARS-CoV-2 infections.

Acknowledgments

We thank colleagues from TTSH’s human resource (Serene Tan and her team) and hospital operations (Michael Leow and his team), departments that worked tirelessly to collate the data on HCP on quarantine and weekly SARS-CoV-2 PCR testing.

Financial support

No financial support was provided relevant to this article.

Conflicts of interest

All authors report no conflicts of interest relevant to this article.

References

Chin, ET, Huynh, BQ, Chapman, LAC, et al. Frequency of routine testing for coronavirus disease 2019 (COVID-19) in high-risk healthcare environments to reduce outbreaks. Clin Infect Dis 2020. doi: 10.1093/cid/ciaa1383.Google ScholarPubMed
Shenoy, ES, Weber, DJ. Routine surveillance of asymptomatic healthcare personnel for severe acute respiratory coronavirus virus 2 (SARS-CoV-2): not a prevention strategy. Infect Control Hosp Epidemiol 2021;42:592597.CrossRefGoogle ScholarPubMed
Chow, A, Htun, HL, Kyaw, WM, Lee, LT, Ang, B. Asymptomatic health-care worker screening during the COVID-19 pandemic. Lancet 2020;396:13931394.Google ScholarPubMed
Htun, HL, Lim, DW, Kyaw, WM, et al. Responding to the COVID-19 outbreak in Singapore: staff protection and staff temperature and sickness surveillance systems. Clin Infect Dis 2020;71:19471952.CrossRefGoogle Scholar
Wang, Y, Tan, JK, Tay, MZ, et al. Dancing with COVID-19 after the hammer is lifted: enhancing healthcare worker surveillance. J Infect 2020;81(6):e13e15.CrossRefGoogle ScholarPubMed
Kyaw, WM, Hein, AA, Zhang, ZX, et al. Healthcare worker acute respiratory illness cluster in 2020: could it be from COVID-19? Infect Control Hosp Epidemiol 2020. doi: 10.1017/ice.2020.364.Google Scholar
Lim, DW, Htun, HL, Wang, Y, et al. Healthcare workers as ‘canaries’ for acute respiratory infections and pathogens during the COVID-19 pandemic. J Hosp Infect 2021;112:119120.CrossRefGoogle ScholarPubMed
Sim, D, Kok, X. ‘Far from out of the woods’: how a COVID-19 variant put Singapore back in defensive mode. South China Morning Post website. https://www.scmp.com/week-asia/health-environment/article/3134497/far-out-woods-how-covid-19-variant-put-singapore-back. Published May 23, 2021. Accessed May 23, 2021.Google Scholar
Figure 0

Table 1. Categories of Healthcare Personnel (HCP) Screened for and Detected With SARS-CoV-2 Infection, April 28–May 22, 2021