Experimental measurements of human cough airflows from healthy subjects and those infected with respiratory viruses

Research concerning person-to-person respiratory virus transmission is required to develop reliable, evidence-based infection prevention and control measures. Experimental studies of human coughs were comprehensively critiqued from the point of view of methodologies, aerodynamics, droplet dispersion and virology. Particle image velocimetry (PIV) and hot-wire anemometry (HWA) measurements were conducted at x=1 m away from the mouth of human subjects to develop a model for cough flow behaviour at greater distances from the mouth than those studied previously. Experiments were conducted for sick subjects who had presented with influenza-like illness, together with a cohort of healthy subjects. Biological aerosol sampling was conducted with sick participants to assess the risk of exposure to airborne viruses. Data were collected and analyzed from 58 subjects, and the results were used to validate computational fluid dynamics (CFD) models. No differences were observed between coughs from sick or healthy subjects, and peak cough jet centre velocities as high as 3.05 m/s (Average Vpeak=1.17 m/s) were measured at approximately x/D = 45