Environmental microorganisms and infection transmission in healthcare buildings

医疗获得性感染（HCAI）仍然是全球性的问题，抗生素耐药性意味着治疗感染变得越来越具有挑战性。越来越多的证据表明，建筑环境在感染的传播途径中起着重要作用。特别是，接触传播可能受到医院环境中表面污染的影响，这也受到空气中微生物流行的影响。虽然人们越来越认识到环境与微生物污染之间的关系，但很少有定量数据来评估空气与表面污染之间的相互作用。此外，大多数研究都是从微生物学或临床角度进行的，并没有充分考虑物理环境或正在发生的活动。因此，没有足够的数据来确定这种关系，并了解这种关系如何随时间而变化。本项目旨在通过建立医院微生物与医院环境设计和运营之间的定量关系来填补这一知识空白。这将导致新的方法来评估环境对感染风险的作用，支持未来的设计和行动，如清洁。该博士学位与EPSRC HECOIRA医疗保健影响合作伙伴项目EP/P023312/1保持一致。该研究的主要目标是：在受控条件下，随着时间的推移，量化空气和表面上微生物之间的关系。这将涉及一系列条件下的生物气溶胶室研究，包括生物气溶胶源，微生物物种，通风流量，温度和湿度，以量化随时间变化的微生物浓度和活力，并建立沉积，蒸发和存活率。这将涉及在两个医院病房进行大量微生物和环境取样以及活动监测研究，以确定空气和表面污染随时间、身体状况和活动的时间序列变化。应用感染风险数学模型中的经验关系，评估医院病房环境中特定事件的清洁程序、手部卫生和环境之间的关系。该项目符合EPSRC在建筑环境和医疗保健技术方面的优先事项。通过将微生物方法学与物理环境及其运行数据相结合，该项目将提供新的见解，为未来的医疗保健产业设计和运营提供信息，并支持患者护理的临床决策。

Healthcare acquired infection (HCAI) remains a problem worldwide and antibiotic resistance means that treating infections is becoming increasingly challenging. There is increasing evidence that the built environment plays an important role in the transmission pathway for infections. In particular, contact transmission can be influenced by the contamination of surfaces in the hospital environment, which is also influenced by the prevalence of microorganisms in the air. While there is growing awareness of the relationships between the environment and microbial contamination, there is very little quantitative data to assess the interactions between air and surface contamination. Moreover the majority of studies have been conducted from a microbiology or clinical perspective and do not fully characterise the physical environment or the activities that are taking place. As such there is not sufficient data to be confident in relationships and to understand how this varies with time.This project aims to fill this gap in knowledge by establishing quantitative relationships between microogansmisms in hospitals and the design and operation of the hospital environment. This will lead to new approaches to assess the role of the environment on infection risk, supporting both future design and actions such as cleaning. The PhD is aligned to the EPSRC HECOIRA Healthcare Impact Partnership Project EP/P023312/1.The key objectives of the study are:Quantify the relationships between microorgansims on the air and on surfaces over time under controlled conditions. This will involve bioaerosol chamber studies for a range of conditions including bioaerosol source, microorganism species, ventilation flow rate, and temperature and humidity, to quantify concentration and viability of microorganisms with time and establish deposition, evaporation and survival rates.Characterise transient relationships between air and surface microbial burden in a hospital environment. This will involve substantial microbial and environmental sampling and activity monitoring studies in two hospital wards to develop time series variations in air and surface contamination with time, physical conditions and activity. Apply empirical relationships within mathematical models of infection risk to evaluate the relationships between cleaning procedures, hand hygiene and the environment on potential infection risks for specific events in hospital ward settings. The project aligns to EPSRC priorities in Built Environment and Healthcare Technology. By integrating microbial methodologies with data on the physical environment and its operation, the project will give new insights to inform future healthcare estates design and operation as well as support clinical decisions over patient care.