The World Health Organization (WHO) recently spearheaded a shift in the foundational understanding of airborne pathogen prevention. This change entails a refined terminology that facilitates better comprehension of airborne disease transmission. An overarching term, in this regard, is promoted in a report from the WHO, similar to commonly used terms – ‘waterborne’ or ‘bloodborne’. The purpose of this new classification is to dispel common medical misconceptions concerning airborne disease transmission.
It is not uncommon for healthcare professionals to understatedly regard airborne pathogens as spreadable only under certain conditions or during aerosol-generating procedures. A prime example of such a misconception was evident at a public health online meeting where the use of N95 masks was recommended only in high-risk settings, instead of as a standard preventive measure against COVID-19 exposure. The advised use of surgical masks instead of N95 masks is largely ineffective against airborne disease transmission.
Pathogen transmission control efforts have often been found lacking, particularly in healthcare facilities witnessed during the 2003 SARS-CoV-2 outbreak in Toronto. In addition, Trisha Greenhalgh and her team, in a recently published Lancet commentary, opined that strategies like wearing a fitted N95 mask or improving indoor ventilation to prevent airborne pathogen spread are frequently overlooked or downplayed.
The WHO’s new description of airborne pathogens is in accordance with the October 2020 National Academy of Sciences report on the airborne transmission of SARS-CoV-2, effectively making the consideration of particle size and large droplet spread redundant. Consequently, it is now essential always to use an N95 mask when exposed to airborne pathogens as they can deposit directly on surfaces.
The professionals working in infection disease control should proactively take actions like using portable CO2 monitors to gauge indoor air quality and press for continuous CO2 monitoring and optimal utilization of HEPA filtrations in facilities. Remember that the sole purpose of N95 masks is to prevent airborne disease transmission; surgical masks are not designed for this task.