The Covid-19 pandemic brought to light a global controversy over defining airborne diseases, with the World Health Organization (WHO) expanding its definition after acknowledging Covid-19 as one in late 2021. Initially, guidance focused on sanitizing surfaces rather than protecting against the airborne spread of the virus.
In November 2021, the WHO assembled experts to update guidelines for classifying routes of pathogen transmission. A report published by these experts outlined new definitions for “through the air transmission” and “airborne transmission/inhalation,” with engineers and aerosol scientists providing a different perspective to the WHO.
The new guidelines reflect the reality that infectious particles range in size and can infect people even at short range. However, there is some disagreement among experts about the implications of these new definitions for informing infection prevention and control policy.
The report suggested the use of airborne precautions in situations involving pathogens that spread through the air, but it is not recommended in all cases. Some experts have criticized that economic and political forces may impact the implementation of these new guidelines.
The WHO chief scientist emphasizes the importance of conducting more science to improve infection control practices going forward. It is crucial to continue studying and understanding the transmission of airborne diseases to better protect public health.
