AUSTIN (KXAN) — On Wednesday, Dr. John Abikhaled, President of Travis County Medical Society, explained the cycle of COVID-19 transmission like this:
“We all know how things go viral on the Internet. You see something funny. A cat video, and you share it with 10 people, and those people share it with 10 people each, so you’re up to 100. And those 100 share it to another 10, so you’re up to 1,000. They keep sharing, and 1,000 becomes 10,000 and then 100,000 and then 1 million. So in only six cycles of transmission, one person can affect one million. Real viruses, like the new coronavirus, work exactly the same way.”
Doctors said those cycles of transmission are a big threat as COVID-19 case numbers spike in Central Texas. As of Wednesday afternoon, Austin Public Health reported more than 6,500 cases.
But the University of Texas at Austin researchers found the actual number of people infected may be double or even triple.
“We know for every case, there’s probably an undetected case,” explained James Scott, Professor of Statistics and Data Science at UT Austin. “And for each one of those, there’s another person out there in the community who is silently spreading the disease. So I would multiply those case numbers by at least two and probably more like four or five if you wanted to get a sense of how many people in Texas are getting infected every day.”
New research published by a group of professors, including Scott, looked at things like how many people had COVID-19 antibodies in New York, hospitalization data in New York and Austin and how infectious one patient can be.
They concluded 56% of people infected are asymptomatic.
“I guess it was more nerve wrecking to think about am I going to wake up feeling sick,” said Michael Wilson, who tested positive for COVID-19, but did not show any symptoms.
He told KXAN the only reason why he got tested and wasn’t surprised with the result is because “my boyfriend got his test results back a day before I did and his were positive, and I didn’t see any way that I wouldn’t have COVID.”
Scott said there’re a lot of people like Wilson who get the coronavirus, but do not get sick. But unlike Wilson, Scott said many people don’t get tested.
“I could be talking to you, you could talk to somebody else, that person could talk to somebody else in a matter of hours, and nobody knows that there’s a chain of transmission through those three, four, five, six people until it’s too late. That’s why silent spread is so scary,” the researcher explained.
Scott told KXAN that’s what makes the coronavirus different than the flu.
With a cold or the flu, “a much larger fraction of infections are taking place when somebody is already showing symptoms,” he said.”
With COVID-19, he said, “The asymptomatic infection or the silent spread phenomenon means that COVID can sneak up on you from someone that you got within six feet, someone you’ve interacted without wearing a mask, and neither of you would ever have any clue that one of you was positive until you got tested later.”
CommUnityCare started testing for asymptomatic patients a few weeks ago. Their positivity rate among those with no symptoms and no known exposure to the virus was 7.5%
