Saliva droplets during speech could transmit coronavirus, study claims

A new study has found that tiny droplets of saliva from people’s mouths when they speak can facilitate the transmission of coronavirus. 

When a person speaks, thousands of these tiny droplets are sprayed outwards per minute and US government scientists are claiming it is sufficient to spread COVID-19.

In the study, which is yet to be peer-reviewed or published, the researchers discovered that the droplets could pose a risk to others if the speaker was infected with the killer virus.

To arrive at their premise, the researchers, led by Adriaan Bax at the US National Institutes of Health (NIH) laboratory of chemical physics, used a planar beam of laser light passing through a dust-free enclosure to detect saliva droplets emitted while speaking.

Findings from the study showed that simple words such as “stay healthy” could “generate thousands of droplets that are otherwise invisible to the naked eye.”

It was however, discovered that the use of face masks reduced the droplets of saliva, hence slowing the chances of the novel disease to spread from one person to another.

The study added that its preliminary findings could “have important implications for pandemic mitigation efforts.”

“Speaking may be a primary mode of transmission of SARS-CoV-2. Considering that reports of asymptomatic transmission account for 50-80% of COVID-19 cases and that saliva has peak viral loads at time of patient presentation, droplet emission while speaking could be a significant factor driving transmission and warrants further study,” said the researchers.

“We used a planar beam of laser light passing through a dust-free enclosure to detect saliva droplets emitted while speaking. We found that saying the words ‘Stay Healthy’ generates thousands of droplets that are otherwise invisible to the naked eye.

“A damp homemade cloth face mask dramatically reduced droplet excretion, with none of the spoken words causing a droplet rise above the background. Our preliminary findings have important implications for pandemic mitigation efforts.”

The study has further ignited debate on whether people should use face masks in public places to prevent spread of the virus or just maintain social distancing.

The US Centers for Disease Control and Prevention (CDC) had urged people to wear face masks when visiting places like pharmacies and grocery stores.

It said such measure could halt the spread of the novel disease in such places where social distancing is difficult to maintain.

The World Health Organization (WHO), however, stated that while face masks may help curb the spread of the novel disease, they were insufficient on their own.