Airborne transmission of disease in hospitals

Abstract

Hospital-acquired infection (HAI) is an important public health issue with unacceptable levels of morbidity and mortality, over the last 5 years. Disease can be transmitted by air (over large distances), by direct/indirect contact or a combination of both routes. While contact transmission of disease forms the majority of HAI cases, transmission through the air is harder to control, but one where the engineering sciences can play an important role in limiting the spread. This forms the focus of this themed volume.In this paper, we describe the current hospital environment and review the contributions from microbiologists, mechanical and civil engineers, and mathematicians to this themed volume on the airborne transmission of infection in hospitals. The review also points out some of the outstanding scientific questions and possible approaches to mitigating transmission.

pH modulates the activity and synergism of the airway surface liquid antimicrobials β-defensin-3 and LL-37

“…Our study also has limitations. Bacterial inocula in vivo will usually be smaller than we used, and thus we may have underestimated the potency of antimicrobials (72,73). Unidentified factors in ASL might enhance or attenuate the activity of antimicrobials; those would have been missing from our preparations.…”

Skin as a potential source of infectious foot and mouth disease aerosols

“…Viral disease spread via skin cell aerosol is given minimal treatment or is entirely absent in recent literature reviews [64][65][66]. Given the potential for skin cells to provide protection to infectious virus against adverse environmental conditions, the management of several viral diseases may also benefit from enhanced dust surveillance and management, and skin decontamination.…”

A Pilot Study of the Noninvasive Assessment of the Lung Microbiota as a Potential Tool for the Early Diagnosis of Ventilator-Associated Pneumonia

“…Exhaled breath contains aerosolized droplets of widely varying size (majority between 5 m m and 100 m m) that carry bacteria, as fi rst described by Flugge in 1897. 32,33 Th ese droplets refl ect the pathogens in the lower respiratory tree, transmitting them to the environment. [32][33][34][35] Th us, we hypothesized that bacteria within these aerosolized breath droplets would collect within the hygroscopic condenser humidifi er/heat and moisture exchanger (HCH/HME) fi lters between the endotracheal tubes and ventilator circuit and provide a quantitative assessment of pulmonary bacterial growth.…”