Ōmura Satoshi Memorial Institute, Kitasato University, 5-9-1 Shirokane, Minato-Ku, Tokyo, 108-8641, Japan.
The Japan Textile Products Quality and Technology Center, 5-7-3 Yamate-dori, Chuo-Ku, Kobe City, Hyogo, 650-0011, Japan.
J Infect Chemother. 2023 Jun;29(6):604-609. doi: 10.1016/j.jiac.2023.02.013. Epub 2023 Mar 7.
Although crowds are considered to be a risk factor for SARS-CoV-2 transmission, little is known about the changes in environmental surface contamination with the virus when a large number of people attend an event. In this study, we evaluated the changes in environmental surface contamination with SARS-CoV-2.
Environmental samples were collected from concert halls and banquet rooms before and after events in February to April 2022 when the 7-day moving average of new COVID-19 cases in Tokyo was reported to be 5000-18000 cases per day. In total, 632 samples were examined for SARS-CoV-2 by quantitative reverse transcription polymerase chain reaction (RT-qPCR) tests, and RT-qPCR-positive samples were subjected to a plaque assay.
The SARS-CoV-2 RNA detection rate before and after the events ranged from 0% to 2.6% versus 0%-5.0% in environmental surface samples, respectively. However, no viable viruses were isolated from all RT-qPCR-positive samples by the plaque assay. There was no significant increase in the environmental surface contamination with SARS-CoV-2 after these events.
These findings revealed that indirect contact transmission from environmental fomite does not seem to be of great magnitude in a community setting.
人群被认为是 SARS-CoV-2 传播的一个风险因素，但当大量人参加活动时，关于病毒对环境表面污染的变化知之甚少。在这项研究中，我们评估了 SARS-CoV-2 对环境表面污染的变化。
在 2022 年 2 月至 4 月期间，当东京每天报告的新 COVID-19 病例的 7 天移动平均值为 5000-18000 例时，我们从音乐厅和宴会厅收集了环境样本，在活动前后进行了检测。总共对 632 个样本进行了定量逆转录聚合酶链反应 (RT-qPCR) 检测，对 RT-qPCR 阳性样本进行了噬菌斑分析。
在环境表面样本中，事件前后 SARS-CoV-2 RNA 的检测率分别为 0%-2.6%和 0%-5.0%。然而，在噬菌斑分析中，所有 RT-qPCR 阳性样本均未分离到有活力的病毒。这些事件后，环境表面 SARS-CoV-2 的污染没有显著增加。
这些发现表明，在社区环境中，间接接触传播似乎不会产生很大的影响。
