INTERDISCIPLINARY researchers recently conducted a review to investigate the airborne transmission of respiratory viruses.
The authors conclude that most of the respiratory viruses, including SARS-CoV-2, spread via aerosols at both short and long ranges.
The researchers write that airborne transmission may be the most dominant transmission route for all respiratory diseases.
In 2016, in the United States, lower respiratory tract infections were the seventh most common cause of death, contributing to around 95,992 deaths.
Traditionally, experts believed contact with contaminated surfaces and inhaling droplets from coughs and sneezes were the main transmission modes of respiratory diseases.
However, a comprehensive review of 206 studies in the journal Science finds that aerosols may be the most dominant transmission route for several respiratory diseases.
AerosolsTrusted Source are tiny particles of “microscopic liquid, solid or semi-solid particles that are so small that they remain suspended in air,” say the authors.
Talking, breathing, coughing, and sneezing can all produce aerosols, but because talking and breathing are regular, these activities transfer more of the virus than more occasional coughing and sneezing.
According to the review authors, aerosols “can remain suspended for many seconds to hours, travel long distances, and accumulate in air in poorly ventilated spaces.”
In contrast, droplets are larger particles that originate from coughing and sneezing that can carry infection over short distances. A distance of up to 0.2 meters (m) provides the optimum distance for the transfer of infection by droplets.
Aerosols carry more of the virus and can penetrate deeper into the lung tissue than droplets, which are too large to reach the lower respiratory tract.
The authors hope that a better understanding of this transmission route will help design better ways to prevent infection.
“This review outlines a new paradigm that would be helpful in assuring better air quality and preventing airborne infectious diseases in the future.“
Prof. Chia Wang told Medical News Today: “I decided to conduct the literature review on this topic at the beginning of the outbreak of COVID-19, with a goal to understand better the transmission pathways of SARS-CoV-2 and other respiratory viruses.”