High-resolution contact data and infectious disease absenteeism in kindergarten populations

Close social interactions are fundamental drivers of infectious disease transmission in early childhood education settings. However, high-resolution empirical contact data from these environments remain scarce, limiting our understanding of transmission dynamics and prevention strategies.

We deployed name-tag devices using Ultra-Wide Band (UWB) technology in a public kindergarten in Shenzhen, China. We recorded close-proximity contact events (≤ 2 m) during a typical school day. Contact events were classified into four risk categories based on duration and proximity. We then conducted a joint analysis of temporally segmented, risk-stratified networks alongside six months of infectious-disease-related absenteeism records.

The study achieved an 88.68% participation rate (282 of 318 children) and full participation of 30 teachers, resulting in 389,617 contact events. On average, each child interacted with 57.91 distinct individuals daily. Outdoor activities involved fewer and lower-risk contacts. In contrast, nap time-a sedentary activity-accounted for the highest proportion of high-risk contact time (14.38%). While children with and without absenteeism records had similar total contact numbers and durations over the full day, those in the absentee group engaged in more high-risk contacts. Specifically, they had longer and more frequent interactions across the medium-low, medium-high, and high risk layers. This disparity diminished when low risk contacts were included. At the class level, absenteeism rates were correlated with the density of medium-high (r = 0.833, p = 0.005) and high risk (r = 0.733, p = 0.025) contact layers.

Our findings reveal substantial structural and contextual heterogeneity within kindergarten contact networks and provide quantitative evidence associating contact patterns with health outcomes. High-resolution proximity data offer valuable insights into transmission risk and inform the design of targeted prevention and risk management strategies in early childhood education settings.