Environmental microorganisms and infection transmission in healthcare buildings

Lead Research Organisation: University of Leeds
Department Name: Civil Engineering


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.


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Studentship Projects

Project Reference Relationship Related To Start End Student Name
EP/N509681/1 01/10/2016 30/09/2021
1955605 Studentship EP/N509681/1 01/10/2017 31/03/2021 Waseem Faeq Hiwar