Experts are advising people to talk less and more quietly after a study confirms that talking loudly produces enough respiratory droplets to spread COVID-19.
Previous studies already revealed that coronavirus is spread via respiratory droplets, or aerosols, when a person coughs or sneezes. This new research, however, determined that speaking loudly for just one minute can emit more than 1,000 virus-containing droplets. What’s more, is that the droplets can remain suspended in the air for up to eight minutes, even after the conversation has ended.
“Speech droplets generated by asymptomatic carriers of SARS-CoV-2 are increasingly considered to be a likely mode of disease transmission,” researchers said.
Researchers also noted that there’s a chance even normal speaking could lead to airborne transmission in more confined spaces.
In the study, people were asked to repeat the phrase, “Stay healthy,” at three different volumes, while sensitive lasers detected the droplets they produced. In every instance, droplets were expelled, but the louder someone spoke, the more droplets were detected.
“Highly sensitive laser light scattering observations have revealed that loud speech can emit thousands of oral fluid droplets per second,” the study reported.
While researchers used data from previous studies to estimate the amount of virus-containing droplets that were expelled, the question of whether speech actually produces a risk of infection seems to be up in the air.
Dr. Ravina Kullar compared it to entering a room after someone with measles has been in there. If you did that, you would likely get sick, due to aerosol particles lingering in the air.
“We’re not seeing the same story for SARS-CoV-2,” Kullar said. “That’s what’s making scientists wonder is it a respiratory or aerosol phenomenon.”
Teresa Murray Amato, MD, chair of emergency medicine at Long Island Jewish Forest Hills said it’s important to note that all of the research is still very new.
“We’re learning how to fly the plane while building it at the same time.”
The consensus among experts on moving forward seems to be that less talking and wearing a mask would be the quickest way to slow transmission of the virus at this point.
Mask up and shut up
“The truth is that if everybody stopped talking for a month or two, the pandemic would probably die off,” Jimenez said.
He also added that speaking quietly, instead of yelling or shouting, reduces viral aerosols by about five times. And being completely silent reduces them by about 50 times.
However, none of this will be possible if Americans don’t all agree to make some changes and take the virus more seriously.
“What we’ve learned from the mask experience is that many Americans don’t like being told what to do if they don’t understand why it’s necessary,” Jiminez said. “People need to understand that this virus is in the air, and that they breathe out 10 times more virus when they are shouting or speaking loudly.”
Dr. Murray Amato agreed, saying our own human nature is exactly what viruses thrive on. So, making some uncomfortable changes for a short period of time is the only way to slow the spread.
“Viruses use human nature and human nature is to be together,” Amato said. “We have to find ways to trick or outsmart the virus. Right now, we don’t have a cure. The only thing we can really do is modify our behavior.”