Soon after the first COVID-19 cases were recorded in January, the CDC determined the virus spreads from person to person, mainly through airborne respiratory droplets when an infected person coughs, sneezes, or talks.
Guidance from the United Kingdom government says clinicians carrying out tasks that could generate airborne droplets of saliva loaded with the virus should use the higher standard of protection, including disposable gowns, filtering respirators and face-shielding visors. So what does this new guidance mean to you and me?
The Centers for Disease Control and Prevention recently published supervision to its How COVID-19 Spreads website. Further, CDC stresses the importance of having effective ventilation in enclosed spaces to prevent and minimize the potential for COVID-19 transmission.
"The people who were infected were in the same space during the same time or shortly after the person with COVID-19 had left", it said.
People are at higher risk of catching it the longer and closer they are to someone who has the virus.
The agency said its recommendations for avoiding the virus remain the same. "Sometimes the infected person was breathing heavily, for example while singing or exercising".
The revised guideline now warns people that people who are 6 feet away from each other too are under risk of getting infected from tiny particles that linger in the air.
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Airborne transmission was said to play a large role in the spread of other diseases like tuberculosis, measles and chicken pox. "Small droplets can also form particles when they dry very quickly in the airstream".
The World Health Organization changed their guidance in July and noted the prevalence of airborne transmission of coronavirus and particles lingering in the air. Hundreds of scientists encouraged the WHO to make the acknowledgement following research and studies. In response, the health agency did acknowledge that there was some evidence of airborne transmission in certain environments.
For more information about how COVID-19 is spread, and for safety measures visit the Centers for Disease Control website.
The CDC says these are rare, and existing advice on protective behaviours - washing hands, wearing face coverings and social distancing - remains the same. In that instance, a singer spread the virus up to 45 feet away and infected more than 50 people.
The CDC also said Monday that "increasing evidence" suggests "children and adolescents can efficiently transmit" COVID-19.
Those reports prompted the CDC to update its guidance about coronavirus transmission, officials have said.