Effectiveness of cough etiquette maneuvers in disrupting the chain of transmission of infectious respiratory diseases

Abstract

BackgroundThe effectiveness of recommended measures, such as “cover your mouth when coughing”, in disrupting the chain of transmission of infectious respiratory diseases (IRD) has been questioned. The objective of the current study was to determine the effectiveness of simple primary respiratory hygiene/cough etiquette maneuvers in blocking droplets expelled as aerosol during coughing.MethodIn this study, 31 healthy non-smokers performed cough etiquette maneuvers in an effort to cover their voluntarily elicited best effort coughs in an open bench format. A laser diffraction system was used to obtain accurate, non-invasive, quantitative, real time measurements of the size and number of droplets emitted during the assessed cough etiquette maneuvers.ResultsRecommended cough etiquette maneuvers did not block the release and dispersion of a variety of different diameter droplets to the surrounding environment. Droplets smaller than one-micron size dominate the total number of droplets leaked when practicing assessed maneuvers.ConclusionsAll the assessed cough etiquette maneuvers, performed as recommended, do not block droplets expelled as aerosol when coughing. This aerosol can penetrate profound levels of the respiratory system. Practicing these assessed primary respiratory hygiene/cough etiquette maneuvers would still permit direct, indirect, and/or airborne transmission and spread of IRD, such as influenza and Tuberculosis. All the assessed cough etiquette maneuvers, as recommended, do not fully interrupt the chain of transmission of IRD. This knowledge urges us all to critically review recommended CE and to search for new evidence-based procedures that effectively disrupt the transmission of respiratory pathogens. Interrupting the chain of transmission of IRD will optimize the protection of first responders, paramedics, nurses, and doctors working in triage sites, emergency rooms, intensive care units, and the general public against cough-droplet-spread diseases.

Trained Community Volunteers Improve Tuberculosis Knowledge and Attitudes Among Adults in a Periurban Community in Southwest Nigeria

“…32 However, it did not improve the practice of appropriately covering of the mouth when coughing, and a higher proportion of people reported the use of hands to cover their mouths instead of the more appropriate handkerchief/tissue or in the absence of that, the crook of the elbow post-versus pre-intervention. Although a recent observational cough etiquette study did not find these commonly publicized respiratory hygiene methods to satisfactorily block droplets that result in transmission of respiratory diseases, like TB, 33 they are still widely advocated by national and international health organizations 34,35 and may remain principal means of prevention of airborne diseases in poorer communities, like Idi Araba. Emphasis should, thus, be placed on encouraging these practices in future community intervention studies.…”

Nonpharmaceutical Measures for Pandemic Influenza in Nonhealthcare Settings—Personal Protective and Environmental Measures

“…Other descriptions of this measure have included turning the head and covering the mouth when coughing and coughing or sneezing into a sleeve or elbow, rather than a hand. The rationale for not coughing into hands is to prevent subsequent contamination of other surfaces or objects (31). We conducted a search on November 6, 2018, and identified literature that was available in the databases during 1946-November 5, 2018.…”

“…The authors did not specify the type of respiratory etiquette used by participants in the study. A laboratory-based study reported that common respiratory etiquette, including covering the mouth by hands, tissue, or sleeve/arm, was fairly ineffective in blocking the release and dispersion of droplets into the surrounding environment on the basis of measurement of emitted droplets with a laser diffraction system (31).…”

Respiratory Infections in the U.S. Military: Recent Experience and Control

“…Additionally, frequent education and oversight of HW, HH, and respiratory hygiene of nonmedical military personnel are required. The implementation of cough etiquette measures, such as "covering your mouth when coughing" (either with your arm or with a tissue), were not adequately shown to reduce the airborne spread of droplets leading to respiratory infection transmission in one experimental study (686); such measures have been promoted by health authorities in the United States (314) and in Europe (687) based on the judgment of public health professionals and have also been adopted by the U.S. military.…”