WHO published a new version of its list of frequently asked questions about COVID-19. It’s the first time the WHO has acknowledged the virus can travel in the air and linger longer than previously thought. Aerosol transmission involves secretions in particles much smaller than those released when a person coughs or sneezes. These particles are produced by speaking loudly, singing or even breathing heavily, after exertion for instance.
The World Health Organization revised its guidelines on key issues concerning how the new coronavirus spreads, saying people who are talking or singing may expel the virus through tiny airborne particles that float through cramped and unventilated spaces such as restaurants or nightclubs, The Wall Street Journal reported.
The WHO said the virus could pass between people more than six feet apart in closed, poorly ventilated rooms like office space. It’s the first time the WHO has acknowledged the virus can travel in the air and linger longer than previously thought. Dr. Paul Sax, an epidemiologist at Brigham and Women’s Hospital said it all depends on the settings you’re in. “Aerosols can float in the air but they also are less likely to have virus in them,” Sax said. “And probably for Covid-19, the key thing is who has been in that room that’s poorly ventilated to generate the aerosols. Has it been someone who is in that couple of day period where individuals are very contagious? Or is it someone who either has recovered already from Covid-19, or is not very contagious? These are all things that play a big role,” CBS Boston wrote.
Some medical procedures can produce very small droplets (called aerosolized droplet nuclei or aerosols) that are able to stay suspended in the air for longer periods of time. When such medical procedures are conducted on people infected with COVID-19 in health facilities, these aerosols can contain the COVID-19 virus. These aerosols may potentially be inhaled by others if they are not wearing appropriate personal protective equipment. Therefore, it is essential that all health workers performing these medical procedures take specific airborne protection measures, including using appropriate personal protective equipment. Visitors should not be permitted in areas where such medical procedures are being performed, according to WHO.
Aerosol transmission involves secretions in particles much smaller than those released when a person coughs or sneezes. These particles are produced by speaking loudly, singing or even breathing heavily, after exertion for instance. Because of their size, they are suspended in the air for longer than normal droplet secretions, and can be moved around by air currents. The importance of recognising the dangers of aerosol transmission lies in the fact that it does not respect social distancing, being able to travel farther than one metre. In addition, someone who is not coughing or sneezing can still produce aerosol droplets, making the use of face masks more important. The WHO has previously dismissed the arguments on aerosol transmission as being based on lab experiments not relevant to real-life conditions. However the evidence produced by the 239 doctors relied on evidence from infections in a Chinese restaurant and during a choir rehearsal, according to The Brussels Times.
There have been reported outbreaks of COVID-19 in some closed settings, such as restaurants, nightclubs, places of worship or places of work where people may be shouting, talking, or singing. In these outbreaks, aerosol transmission, particularly in these indoor locations where there are crowded and inadequately ventilated spaces where infected persons spend long periods of time with others, cannot be ruled out. More studies are urgently needed to investigate such instances and assess their significance for transmission of COVID-19, The World Health Organization stated.
Knowing when an infected person can spread SARS-CoV-2 is just as important as how the virus spreads. WHO has recently published a scientific brief outlining what is known about when a person may be able to spread, based on the severity of their illness. Read more here
Coronavirus is continuing its spread across the world, with more than 12 million confirmed cases in 188 countries. At least half a million people have lost their lives. The virus, which causes the respiratory infection Covid-19, was first detected in the city of Wuhan, China, in late 2019. It then spread quickly across the globe in the first months of 2020, reaching 12 million confirmed cases in early July. Europe and North America saw the first major outbreaks in April but as they began to ease, Latin America and Asia started seeing an increase in cases. North America has seen a resurgence of infections in recent weeks, mostly driven by new outbreaks in the US, but Mexico has also seen an increasing numbers of cases, according to BBC.