Respiratory Infectious Disease Transmission in a Nursing Home Based on Real Close-Contact Behaviors.

AIM: Nursing homes, where older residents live in dense clusters, are highly susceptible to epidemics, leading to high infection and mortality rates. This study aims to identify high-risk environments for infection in nursing homes and develop precise intervention strategies based on the behavioral characteristics of the elderly.

METHODS

Non-intrusive fixed RGB-D cameras with computer vision technology were used to automatically collect real close-contact behavioral data of older residents. A close-contact transmission model was developed using SARS-CoV-2 as an example, incorporating real behavioral patterns and the aerosol emission characteristics of older adults during exhalation. Individual viral exposure, infection risks, and intervention effectiveness were calculated.

RESULTS

Close-contact rates in the canteen and painting room both exceeded 60%, while face-to-face contact was most frequent in the billiard room (23.5%). Assuming a prevalence of 1%, the hourly infection risks were 2.0% in the canteen, 1.6% in the painting room, and 0.5% in the billiard room. Universal use of N95 respirators and surgical masks reduced infection risk by 94.1% and 52.1%, respectively. Maintaining interpersonal distance of at least 1.5 m reduced risk by 66.4%. The strategy of opening and closing different types of indoor environments was also analyzed.

CONCLUSIONS

Real close-contact behaviors of older residents strongly influence respiratory infection risks in nursing homes. This study helps identify high-risk environments for infection in nursing homes and enables the precise development of intervention based on the behavioral characteristics of older adults.