Centro di Referenza Nazionale per l'Analisi e Studio di Correlazione tra Ambiente, Animale e Uomo, Istituto Zooprofilattico Sperimentale del Mezzogiorno, Via Salute n. 2, 80055 Portici, Italy.
Department of Food Security Coordination, Istituto Zooprofilattico Sperimentale del Mezzogiorno, Via Salute n. 2, 80055 Portici, Italy.
Int J Environ Res Public Health. 2022 May 11;19(10):5861. doi: 10.3390/ijerph19105861.
The SARS-CoV-2 can spread directly via saliva, respiratory aerosols and droplets, and indirectly by contact through contaminated objects and/or surfaces and by air. In the context of COVID-19 fomites can be an important vehicle of virus transmission and contribute to infection risk in public environments. The aim of the study was to analyze through surface sampling (sponge method) the presence of SARS-CoV-2 in public and working environments, in order to evaluate the risk for virus transmission. Seventy-seven environmental samples were taken using sterile sponges in 17 animal farms, 4 public transport buses, 1 supermarket and 1 hotel receptive structure. Furthermore, 246 and 93 swab samples were taken in the farms from animals and from workers, respectively. SARS-CoV-2 detection was conducted by real-time RT-PCR and by digital droplet RT-PCR (dd RT-PCR) using RdRp, gene E and gene N as targets. None of the human and animal swab samples were positive for SARS-CoV-2, while detection was achieved in 20 of the 77 sponge samples (26%) using dd RT-PCR. Traces of the RdRp gene, gene E and gene N were found in 17/77 samples (22%, average concentration 31.2 g.c./cm, range 5.6 to 132 g.c./cm), 8/77 samples (10%, average concentration 15.1 g.c./cm, range 6 to 36 g.c./cm), and in 1/77 (1%, concentration 7.2 g.c./cm). Higher detection rates were associated with sampling in animal farms and on public transport buses (32% and 30%) compared to the supermarket (21%) and the hotel (no detection). The result of the study suggests that the risk of contamination of surfaces with SARS-CoV-2 increases in environments in which sanitation strategies are not suitable and/or in highly frequented locations, such as public transportation. Considering the analytical methods, the dd RT-PCR was the only approach achieving detection of SARS-CoV-2 traces in environmental samples. Thus, dd RT-PCR emerges as a reliable tool for sensitive SARS-CoV-2 detection.
SARS-CoV-2 可以通过唾液、呼吸道飞沫和液滴直接传播，也可以通过接触污染的物体和/或表面以及空气间接传播。在 COVID-19 背景下，病原体可能是病毒传播的重要载体，并导致公共环境中的感染风险增加。本研究的目的是通过表面采样（海绵法）分析 SARS-CoV-2 在公共和工作环境中的存在情况，以评估病毒传播的风险。在 17 个动物养殖场、4 辆公共交通巴士、1 家超市和 1 家酒店接待机构中，使用无菌海绵采集了 77 个环境样本。此外，在农场中分别从动物和工人身上采集了 246 个和 93 个拭子样本。使用 RdRp、基因 E 和基因 N 作为靶标，通过实时 RT-PCR 和数字液滴 RT-PCR（dd RT-PCR）检测 SARS-CoV-2。人类和动物拭子样本均未检测到 SARS-CoV-2，而在 77 个海绵样本中，dd RT-PCR 检测到 20 个样本（26%）为阳性。在 17/77 个样本（22%，平均浓度为 31.2 g.c./cm，范围为 5.6 至 132 g.c./cm）、8/77 个样本（10%，平均浓度为 15.1 g.c./cm，范围为 6 至 36 g.c./cm）和 1/77 个样本（1%，浓度为 7.2 g.c./cm）中检测到 RdRp 基因、基因 E 和基因 N 的痕迹。在动物养殖场和公共交通巴士（32%和 30%）中，与超市（21%）和酒店（未检测到）相比，采样的检出率更高。研究结果表明，在卫生策略不适当和/或人员高度密集的环境中，表面被 SARS-CoV-2 污染的风险增加，例如公共交通。就分析方法而言，dd RT-PCR 是唯一能够在环境样本中检测到 SARS-CoV-2 痕迹的方法。因此，dd RT-PCR 是一种可靠的敏感 SARS-CoV-2 检测工具。
