The World Health Organization's Director of Emergencies Dr. Mike Ryan told a panel of experts on Monday that the global health agency's "best estimates" indicate that nearly 1 in 10 people worldwide may be been infected with COVID-19, far above global confirmed cases and consensus data.
Speaking to a special session of the agency's 34-member executive board, Ryan stated that while actual infection rates vary from urban to rural groups, the majority of the world is still at risk for contracting the coronavirus, a warning the W.H.O. has raised on multiple occasions.
"Our current beat estimates tell us that about 10% of the global population may have been infected by the virus," Ryan stated, according to the Associated Press. At that estimate, more than 760 million people have been infected with COVID-19 since December 2019, based on the current world population of roughly 7.6 billion.
While health experts, including the W.H.O., have warned that the number of confirmed cases may be an underestimate of the pandemic's full picture, the W.H.O.'s new estimate is 20 times more than current consensus data that shows that more than 35 million people have been infected globally.
Updated Guidance
The U.S. Centers for Disease Control and Prevention announced on Monday that the agency has updated its guidance on how the coronavirus spreads on its website, with the federal health agency now stating that COVID-19 can spread through airborne transmission.
The new guidance comes a few weeks after the agency published a similar warning, only to retract it after saying the information was published by mistake.
In the new guidance, the C.D.C. states that "some infections can be spread by exposure to virus in small droplets and particles that can linger in the air for minutes to hours. These viruses may be able to infect people who are further than 6 feet away from the person who is infected or after that person has left the space."
The agency's new guidance also stated that there is some evidence that in certain conditions--like enclosed spaces with inadequate ventilation--the virus was able to transmit to individuals at distances over 6 feet. In those cases, the amount of infectious airborne particles--which are much smaller than the large respiratory droplets that expel when an individual coughs and sneezes and fall quickly to the ground--produced by an individual become concentrated enough to spread the virus.
The C.D.C. believes that close-contact transmission is the most common way an individual becomes infected with COVID-19. However, other scientists believe that airborne particles are a more major source of coronavirus transmission.
In an open letter published in the medical journal Science on Monday, researchers stated that there is "overwhelming evidence" that the coronavirus is majorly spread through aerosol transmission.
"There is an urgent need to harmonize discussions about modes of virus transmission across disciplines to ensure the most effective control strategies and provide clear and consistent guidance to the public," the scientists wrote in the letter.
Researchers noted that many individuals who are infected with COVID-19 have no symptoms, but are able to release infected particles into the air through breathing and talking, thus infecting those who breathe in those droplets.
The authors of the letter stressed that it is important to urge public health officials to issue guidance on proper indoor ventilation and filtration, as well as moving more activities outdoors and encouraging mask-wearing no matter the distance between individuals.
