Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland.
Laboratory of Environmental Chemistry, School of Architecture, Civil, and Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
PLoS One. 2020 Sep 17;15(9):e0238998. doi: 10.1371/journal.pone.0238998. eCollection 2020.
The frequent contact people have with liquids containing pathogenic microorganisms provides opportunities for disease transmission. In this work, we quantified the transfer of bacteria-using E. coli as a model- from liquid to skin, estimated liquid retention on the skin after different contact activities (hand immersion, wet-cloth and wet-surface contact), and estimated liquid transfer following hand-to-mouth contacts. The results of our study show that the number of E. coli transferred to the skin per surface area (n [E. coli/cm2]) can be modeled using n = C (10-3.38+h), where C [E. coli/cm3] is the concentration of E. coli in the liquid, and h [cm] is the film thickness of the liquid retained on the skin. Findings from the E. coli transfer experiments reveal a significant difference between the transfer of E. coli from liquid to the skin and the previously reported transfer of viruses to the skin. Additionally, our results demonstrate that the time elapsed since the interaction significantly influences liquid retention, therefore modulating the risks associated with human interaction with contaminated liquids. The findings enhance our understanding of liquid-mediated disease transmission processes and provide quantitative estimates as inputs for microbial risk assessments.
人们经常接触含有致病微生物的液体，这为疾病传播提供了机会。在这项工作中，我们使用大肠杆菌作为模型，定量了细菌从液体到皮肤的转移，估计了不同接触活动（手浸入、湿布和湿表面接触）后皮肤对液体的保留情况，并估计了手到口接触后的液体转移。我们的研究结果表明，每单位皮肤表面积转移到皮肤上的大肠杆菌数量（n [大肠杆菌/cm2]）可以用 n = C（10-3.38+h）来建模，其中 C [大肠杆菌/cm3]是液体中大肠杆菌的浓度，h [cm]是保留在皮肤上的液体的膜厚度。大肠杆菌转移实验的结果表明，大肠杆菌从液体转移到皮肤与之前报道的病毒从液体转移到皮肤之间存在显著差异。此外，我们的结果表明，相互作用后经过的时间显著影响液体保留，从而调节了与受污染液体的人类相互作用相关的风险。这些发现增进了我们对液体介导疾病传播过程的理解，并提供了定量估计值作为微生物风险评估的输入。
