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Prominent San Diego Scientists Argue COVID-19 Spreads Like Secondhand Smoke

A nurse preparing the COVID-19 vaccine at San Diego State University's Viejas...

Photo by Roland Lizarondo

Above: A nurse preparing the COVID-19 vaccine at San Diego State University's Viejas Arena, March 23, 2021.

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Two San Diego researchers hope a new peer-reviewed article helps them convince federal officials to change their opinion of how COVID-19 spreads.

Aired: April 20, 2021 | Transcript

A new report in the medical journal The Lancet says COVID-19 is spread primarily by small aerosol particles.

Two UC San Diego researchers, Robert Schooley and Kim Prather, are among the co-authors.

The scientists make the case that the coronavirus has spread so efficiently because it is passed along by small aerosols that are released by the simple acts of breathing and talking.

The researchers likened the aerosols to secondhand smoke which can fill a room and stay there even after an infected person has left. But unlike secondhand smoke, aerosols are too small to be seen and people cannot smell them.

Reported by Erik Anderson

RELATED: San Diego Scientists Among Group Calling On CDC To Tighten COVID-19 Guidance

“This is not a virus transmitted by droplets at close range,” said Robert Schooley, an infectious disease expert at UC San Diego. “Or by touching things. It’s primarily transmitted when we breathe. If we breathe in air from someone who has the virus just breathed out, the virus gets into our lungs and the disease can start.”

The Lancet article examined 25 peer-reviewed studies that the authors say prove aerosol transmission is the primary pathway to infection.

“I think people who aren’t vaccinated should be very cautious about being indoors with other people in places where the masks come off. That would be places like restaurants and bars and gyms,” Schooley said.

The science does not support the idea that contamination from surfaces or coughing and sneezing are the major pathways the virus spreads.

“There is actually a shocking lack of evidence for the pathways that the CDC [Centers for Disease Control] and WHO [World Health Organization] say are major,” said Jose Jimenez, an atmospheric chemist at the University of Colorado.

Jimenez said the evidence shows the risk of infection rises dramatically indoors and that should be proof enough that the Centers for Disease Control needs to update its guidance.

RELATED: San Diego International Airport Workers Asking For COVID-19 Vaccine

“They are quite a bit behind the science,” Jimenez said. “And they need to update their recommendations because some of the things they are saying are not sufficient. The masks that people who are at high risk are wearing need to be improved.”

The co-authors have been frustrated by their inability to change the COVID-19 guidance offered by the Biden Administration and the CDC.

The researchers hope publishing their findings in a major peer-reviewed journal like The Lancet will convince public health officials to improve their advice.

Listen to this story by Erik Anderson.

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Erik Anderson
Environment Reporter

opening quote marksclosing quote marksI focus on the environment and all the implications that a changing or challenging environment has for life in Southern California. That includes climate change, endangered species, habitat, urbanization, pollution and many other topics.

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