Studies describing reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay-based infection control strategies (LAMP-based ICSs) for 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 cases, such as those with a history of exposure to COVID-19 cases and/or bilateral-ground glass opacities (bGGO) on chest CT. Of 212 cases, which included 13 confirmed COVID-19 cases in the diagnostic cohort, exposure to COVID-19 cases (P<0.0001) and chest CT bGGO (P=0.0022) were identified as significant predictors of COVID-19. In the 173 hospitalized cases for whom results of the first RTLAMP were negative, the durations of ICPs were significantly longer in cases with exposure to COVID-19 cases and/or a high clinical index of suspicion and cases with bGGO than in the remaining cases (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.