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Author Spotlight: Advancing Pathogen Diagnostics with Standardized LAMP
Published on: September 8, 2023
DNA amplification tests at universal pre-admission screening with enhanced precaution strategies for asymptomatic
Itaru Nakamura1, Yusuke Watanabe1, Hiroaki Fujita1
1Department of Infection Prevention and Control, Tokyo Medical University Hospital, Tokyo, Japan.
Objective:
To analyse the effect of hospital pre-admission screening and enhanced precaution strategies on the transmission of severe acute respiratory syndrome coronavirus-2.
Methods:
This retrospective cohort study was conducted over 17 months from 11 May 2020 to 30 September 2021 at a large hospital in Tokyo. Universal DNA amplification tests were conducted during pre-admission screening, and enhanced precaution strategies were implemented for all patients with negative admission tests. The primary outcome was the occurrence of symptomatic coronavirus disease 2019 (COVID-19) in patients after admission. The secondary outcomes were time-series analyses of monthly positive admission test numbers, positive rates, clinical features in positive cases, and clinically confirmed nosocomial transmission.
Results:
In total, 32,081 patients were screened pre-admission (29,556 asymptomatic patients and 2525 symptomatic patients). Of the asymptomatic patients, 0.11% (n=32) tested positive and were admitted to a designated COVID-19 ward or were not admitted. Among the five inpatients who developed symptomatic COVID-19 during hospitalization, only two cases were related to a single nosocomial transmission.
Conclusion:
Pre-admission test screening was effective in identifying asymptomatic cases of COVID-19. This allowed administrators to quarantine patients or delay hospital admission. The combination of testing and enhanced precaution strategies for asymptomatic cases of COVID-19 may minimize nosocomial transmission.

