Filenews 21 April 2021
Opening the windows and ventilating the space should be at the heart of efforts to prevent the spread of COVID-19, argues a team of experts from the University of Leicester and the Polytechnic University of Virginia, considering that confusion about the transmission of the virus through the air means that this simple measure has been overlooked.
Evidence-based scientific evidence has convinced many countries to adopt recommendations for masking, and health authorities have argued for months that overcrowded interiors and poor ventilation put people at increased risk.
The virus is more likely to be transmitted through breathing in close proximity to another human than by contact with surfaces or from a distance, experts say in a report published in the BMJ. However, the role of air transmission receives only a brief reference to the instructions for controlling infection.
"People are much more likely to become infected in a room with closed windows or a lack of ventilation system," say authors Julian Tang and Linsey Marr, stressing that part of the problem is the fact that the terms "droplets" and "airborne" relating to the description of coronavirus transmission are not clear.
"Essentially, a person who inhales particles – regardless of size or name – inhales aerosols. Although this can happen from a long distance, it is more likely when we are close to someone else, as aerosols between two people are much more concentrated nearby, such as when we are close to someone who smokes," the experts note.
At the start of the pandemic, health authorities, including the World Health Organization, rejected the possibility that infectious micro-droplets could be transported into the air through simple breathing. But they revised their positions after pressure from experts and the evidence that emerged along the way.
The report in the scientific journal BMJ states that preventive measures such as mask use, social distance and indoor overcrowding can help reduce the spread curve of the virus, whether through inhaled particles or through direct contact with surfaces.
It stresses, however, that the crucial difference lies "in the need for further emphasis on ventilation, as even the smallest suspended particles can remain in the air for several hours, contributing significantly to transmission".
In March, the World Health Organization issued a guidance document encouraging better ventilation in buildings, which states that although the "knowledge gap" remains, transmission of the virus that causes COVID-19 is particularly high indoors where many people are located and there is no good ventilation.
Source: ygeiamou.gr
