Appraising healthcare ventilation design from combined infection control and energy perspective

This paper considers an approach for assessing the balance between energy use and infection control in hospital ward ventilation by combining a stochastic disease outbreak model with a cost evaluation. Disease dynamics are simulated using an SEIR infection modelling approach, with the contact rate due to airborne transmission incorporated through coupling with the Wells-Riley model. Results presented for a hypothetical ward scenario demonstrate that stochastic effects in a small population, such as a hospital, are a controlling factor in the risk of an outbreak and that conventional deterministic models may give misleading results. Cost appraisals clearly show the trade-off between ventilation provision and infection risk depends on many factors including the disease characteristics, people concerned, ventilation system design and rate and the costs of both providing ventilation and treating infections. Although limitations in the input data currently reduce the robustness of the outputs, the approach is shown to be a useful framework for a tool that can quantitatively assess ventilation design from different perspectives for healthcare environments. The paper also highlights some of the knowledge required from further research to enable better quantification of the behaviour of pathogens and the transmission processes for hospital infections.