Reverse Transcription Loop-Mediated Isothermal Amplification Assay-Based Infection Control Strategies for COVID-19 in a Hospital Under the State of Emergency in Tokyo, Japan in Spring 2020.

Studies describing reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay-based infection control strategies (LAMP-based ICSs) for coronavirus disease 2019 (COVID-19) are limited. We reviewed the medical records of cases in which RT-LAMP was performed. Standard ICSs and LAMP-based ICSs were implemented during the study period. The strategies were intended to impose longer periods of infection control precautions (ICPs) for specific patients, such as those with a history of exposure to COVID-19 patients and/or bilateral ground glass opacities (bGGO) on chest computed tomography (CT). Of 212 patients, which included 13 confirmed COVID-19 patients in the diagnostic cohort, exposure to COVID-19 patients (P <0.0001) and chest CT bGGO (P = 0.0022) were identified as significant predictors of COVID-19. In the 173 hospitalized patients in which the results of the first RT-LAMP were negative, the duration of ICPs was significantly longer in patients with exposure to COVID-19 and/or a high clinical index of suspicion and patients with bGGO than in the remaining patients (P = 0.00046 and P = 0.0067, respectively). Additionally, no confirmed COVID-19 cases indicating nosocomial spread occurred during the study period. Establishing a comprehensive system that combines rational LAMP-based ICSs with standard ICSs might be useful for preventing nosocomial spread.