Abstract
ABSTRACT It is generally recognized that most nosocomial infections are spread by exposure to expelled particles at close range (usually within 1 m) or through contact. Although the Korea Centers for Disease Control established a 2-m cut-off for transmittance from patients during the Middle East Respiratory Syndrome (MERS) outbreak in Korea in 2015, questions have been raised regarding possible infection due to aerosols transported beyond this distance. The aim of this study was to characterize cough-generated aerosol emissions from cold patients and to determine the transmission distance of cough particles in indoor air. The study was conducted using subjects with acute upper respiratory infections. The number and size distribution of the particles generated from each cough were measured after participants coughed into a stainless steel chamber in a clean room. The total particle concentration was measured for each subject in the near field ( 2 m). The number of particles emitted by the cough of an infected patient was 560 ± 5513% greater than that generated by patients after recovery (P < 0.001). The number of particles was also significantly higher (P < 0.001) than the background concentration when infected patients were coughing, even in the far field. These results suggest that the 2-m cut-off should be reconsidered to effectively prevent airborne infections.
Highlights
Infectious diseases have many pathways of transmission
Many nosocomial infections are associated with direct person-to-person contact in indoor environments, there is a strong association between the transmission of many pathogens, such as measles, smallpox, tuberculosis, and severe acute respiratory syndrome (SARS), and indoor air movement (Li et al, 2007)
Cough volume and cough peak flow rate were measured during illness and after recovery, whereas the forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and peak expiratory flowrate (PEF) of subjects were measured when they were ill
Summary
Infectious diseases have many pathways of transmission. Infectious disease transmission through respiratory secretions can be divided into droplet transmission and airborne transmission. The World Health Organization (2014) defined droplet transmission as the transmission of diseases by particles expelled at close range, usually within 1 m from the site of generation, and occasionally through contact. They recommended a 5-μm aerosol diameter cut-off to classify droplet (> 5 μm) or airborne (< 5 μm) transmission. Several studies of the airborne transmission of infectious pathogens in indoor environments, using this framework of single cutoff delineation, have failed to acknowledge the size of particles. Some studies have suggested that infections are airborne-transmitted among humans in healthcare settings, because epidemic diseases, such as influenza, are
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
