Coronavirus could stay in the air for up to 14 minutes when people talk loudly: Study

A woman opens her mouth for a heath worker to collect a sample for coronavirus testing during the screening and testing campaign aimed to combat the spread of COVID-19 at Alexandra township in Johannesburg, South Africa. (Reuters)

Speech droplets from people talking loudly in confined spaces could result in coronavirus remaining in the air for more than eight minutes at least, according to a new study by researchers from the US National Institutes of Health.

Researchers used an intense sheet of laser light to visualize bursts of speech droplets produced during repeated spoken phrases. Researchers achieved this by having volunteers repeat the phrase “stay healthy” for 25 seconds. The phrase was chosen because the “th” sound in the word “healthy” was found to be an efficient generator of oral fluid speech droplets.

They found that loud speech can emit thousands of oral fluid droplets per second.

For all the latest headlines follow our Google News channel online or via the app.

“In a closed, stagnant air environment, they disappear from the window of view with time constants in the range of 8 to 14 min,” read the abstract of the research, published in the open-access journal Proceedings of the National Academy of Sciences (PNAS).

Chart (A) shows particle count per frame versus time, with the red curve representing the top 25 percent in scattering brightness and the green curve representing the rest. Image (B) shows the sum of 144 consecutive frames (spanning 6 s) extracted shortly after the end of the 25-s burst of speaking. (Research by Stadnytskyi et al.)

Chart (A) shows particle count per frame versus time, with the red curve representing the top 25 percent in scattering brightness and the green curve representing the rest. Image (B) shows the sum of 144 consecutive frames (spanning 6 s) extracted shortly after the end of the 25-s burst of speaking. (Research by Stadnytskyi et al.)

“These observations confirm that there is a substantial probability that normal speaking causes airborne virus transmission in confined environments,” the researchers added.

The new research study is important as it raises questions whether the mere act of an infected patient talking loudly could be a factor in transmitting the coronavirus to other people.

Visit our dedicated coronavirus site here for all the latest updates.

According to the World Health Organization, the COVID-19 coronavirus spreads primarily through droplets of saliva or discharge from the nose when an infected person coughs or sneezes.

The novel coronavirus has killed at least 294,199 people since the outbreak first emerged in China last December, according to a tally from official sources compiled by AFP.

Read more:

Research predicts ‘end date’ of coronavirus crisis in US, UK, Italy, France, Spain

Coronavirus: Two strains, 70 mutations of COVID-19 exist in the UAE, study finds

Coronavirus may disappear before development of a vaccine: Milan research center head

SHOW MORE
Last Update: Wednesday, 20 May 2020 KSA 14:07 - GMT 11:07
Top