Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China.
Institute of Public Safety Research, Department of Engineering Physics, Tsinghua University, Beijing, China.
Indoor Air. 2018 Nov;28(6):963-972. doi: 10.1111/ina.12505. Epub 2018 Oct 1.
Fomites transmit infection. A key question is how surface contamination in a building is spread by human touch. Using video cameras, we collected more than 120 000 touch actions from 60 hours of high-resolution data on surface touch across five typical weekdays in a graduate student office. The students touched surfaces with one or both hands during 94.6% of the observed period. On average, each student made five touches per minute, with an average duration of 22 seconds per touch. High-touch and high-risk surfaces and people were identified. 98.8% of the surfaces touched, such as mobile phones and human faces, were private, but public surfaces, such as a water dispenser button, were touched by 68% of the students in the office on average. Compared with females, males spent 3% more time touching surfaces. Right hands always had higher touch frequency than left hands. The surface network in the office was scale-free, whereas the hand network was small-world. The results revealed power law and logistic growth in the number of contaminated surfaces which suggests that fomite transmission can be extremely effective. The time taken for most surfaces to be contaminated after one surface became contaminated was much shorter for public than for private surfaces.
污染物传播感染。一个关键问题是建筑物表面污染如何通过人类接触传播。我们使用摄像机，从一个研究生办公室五天的高分辨率表面接触数据中收集了超过 12 万次触摸动作。在观察期间的 94.6%时间内，学生们用一只或两只手触摸表面。平均而言，每个学生每分钟触摸五次，每次触摸持续 22 秒。确定了高接触和高风险的表面和人。接触到的 98.8%的表面，如手机和人脸，都是私人的，但办公室里的平均有 68%的学生触摸公共表面，如饮水机按钮。与女性相比，男性触摸表面的时间多 3%。右手的触摸频率总是高于左手。办公室的表面网络是无标度的，而手部网络是小世界的。结果表明，污染表面的数量呈幂律和逻辑增长，这表明污染物传播可能非常有效。从一个表面被污染到大多数表面被污染所花费的时间，对于公共表面来说比私人表面要短得多。
