These days hearing someone cough or sneeze in public can cause instant anxiety if you’re nearby, especially in closed spaces.
But how often do you think of the other major route for COVID-19 — the simple act of talking to another person?
Droplets spewed during speech are believed to be the key transmission vector for COVID-19 for asymptomatic and presymptomatic patients, says research scientist Jeremy P. Howard, co-founder of fast.ai , which promotes deep learning via artificial intelligence.
Asymptomatic infections may account for 40-45 percent of all COVID-19 cases, according to a new Scripps Research Institute analysis published this month in the Annals of Internal Medicine. An additional percentage of cases, yet unknown, involve presymptomatic patients.
"Our estimate of 40 to 45 percent asymptomatic means that, if you’re unlucky enough to get infected, the probability is almost a flip of a coin on whether you’re going to have symptoms. So to protect others, we think that wearing a mask makes a lot of sense," Scripps Research behavioral scientist Daniel Oran told Science News.
COVID-19 results in viral shedding in the upper respiratory tract, where droplets can form. The picture above shows speech droplets, which are believed to be the key transmission vector for COVID-19, with vs without a paper towel face cover. As you see, nearly all droplets are blocked.
Here’s a video with a cloth covering, from this NEJM paper: https://t.co/QoGBBZpQEa pic.twitter.com/HGqz3U7NQU — Jeremy #Masks4All Howard (@jeremyphoward) June 19, 2020 Every time people speak, they spray a cloud of droplets that vary widely in size. Large droplets fall quickly to the ground, but small ones can dehydrate and linger as “droplet nuclei” in […]