Detailed Contact Data and the Dissemination of Staphylococcus aureus in Hospitals

Close proximity interactions (CPIs) measured by wireless electronic devices are increasingly used in epidemiological models. However, no evidence supports that electronically collected CPIs inform on the contacts leading to transmission. Here, we analyzed Staphylococcus aureus carriage and CPIs recorded simultaneously in a long-term care facility for 4 months in 329 patients and 261 healthcare workers to test this hypothesis. In the broad diversity of isolated S. aureus strains, 173 transmission events were observed between participants. The joint analysis of carriage and CPIs showed that CPI paths linking incident cases to other individuals carrying the same strain (i.e. possible infectors) had fewer intermediaries than predicted by chance (P S. aureus transmission was consistent with contacts defined by electronically collected CPIs, illustrating their potential as a tool to control hospital-acquired infections and help direct surveillance.通过无线电子设备采集的近距离交互（Close Proximity Interactions，CPIs）正日益被应用于流行病学模型。然而目前尚无证据表明，电子手段获取的CPIs能够反映导致病原体传播的实际接触行为。本研究于某长期护理机构开展，为期4个月，同步采集了329名患者与261名医护人员的金黄色葡萄球菌（Staphylococcus aureus）定植情况与CPIs数据，以验证上述假说。在分离得到的多样化金黄色葡萄球菌菌株中，研究人员共观测到173起受试者之间的传播事件。对定植情况与CPIs的联合分析显示，将新增病例与携带同一菌株的其他个体（即潜在传染源）连接起来的CPI路径，其中间节点数量少于随机预期（P < 0.001，Wilcoxon符号秩检验）。研究结果表明，金黄色葡萄球菌的传播与电子手段采集的CPIs所定义的接触模式相符，这说明CPIs可作为控制医院获得性感染、辅助指导监测工作的有效工具。