The careful and data-driven UCSF chair of medicine Dr. Bob Wachter has reached a new pandemic milestone: He’s ready to dine indoors and ditch his mask in uncrowded indoor settings.
In a characteristically lengthy Twitter thread Sunday afternoon, Wachter broke down his reasoning, calculating that his chances of dying from an indoor maskless dinner are about 1 in 200,000 – “consistent with other risks we all take to do some things we enjoy.”
Just three weeks ago, Wachter, who has garnered a huge social media following for his COVID-19 advice, tweeted that he was not ready to lose his mask or dine indoors. That he now feels ready to take both steps signals that the local COVID-19 situation has improved to the point where even some of the most cautious feel comfortable re-engaging in pre-pandemic pastimes.
The same day, President Joe Biden said the pandemic is “over” on “60 Minutes” while walking around the Detroit auto show. The U.S. government still designates COVID-19 as a public health emergency, which ensures expanded Medicare coverage, telehealth services and other pandemic measures to remain in place.
“We still have a problem with COVID. We’re still doing a lot of work on it. But the pandemic is over. If you notice, no one is wearing masks. Everyone seems to be in pretty good shape,” Biden said.
Cases are flat or falling in nearly every state, though about 400 people in the U.S. still die from COVID-19 each day, according to New York Times data. Last week, director-general of the World Health Organization Tedros Ghebreyesus said the end of the pandemic is “not there yet” but “in sight.”
Wachter will still wear his mask in crowded or poorly ventilated indoor spaces or on an airplane – “probably forever,” he wrote. In a group of 150 people on a packed plane, there’s a 78% chance that at least one person is infectious, Wachter wrote.
“I figure, why take ANY risk in situations like these?” Wachter said.
Wachter’s threshold to “liberalize” his behavior is when daily cases fall below 5 for every 100,000 in the region, Wachter repeated in his Sunday thread. San Francisco is at 6 per 100,000 according to New York Times data, a 64% drop in the last two weeks, Wachter pointed out.
After accounting for home tests, 5 cases per 100,000 is “really” about 25 cases per 100,000, Wachter said in his thread. California is at 12 cases per 100,000 people, while the U.S. is at 19 cases per 100,000, per New York Times data.
The asymptomatic test positivity rate at UCSF hospitals is now 1.6% – down from 4 to 6% in early August, according to Wachter, another sign of improvement in the local COVID-19 situation in the last month.
That approximates to about 1 in 100 people in San Francisco being infectious, or about a 10% chance in a group of 10 people that at least one will be infectious, Wachter said.
“So if I dine today in a restaurant in San Francisco, there’s a 1 in 10 chance that at least one infectious person will be nearby,” Wachter wrote. The risk of “meal-length exposure to an infectious person” is dependent on many factors – ventilation, distance, vaccination status – but Wachter estimated it to be about 10%.
Together, that’s about a 1% chance of being infected during an indoor meal.
That leads to about 1 in 1,000 odds of getting long COVID from dining indoors, and 1 in 200,000 chance of dying, Wachter said.
What to do about those odds? It depends on each person’s risk status and tolerance, Wachter wrote. Ultimately, he said he shares his reasoning to help others consider their situation.
“If you’ve been in careful mode, as I’ve been, are these risks now low enough to enjoy indoor dining in SF? To me, they are. Are they low enough to leave the mask off when entering an uncrowded indoor space or having a small group work meeting? To me, yes,” Wachter said.
“For you? Your call. I hope this helps you think it through,” Wachter said.
Claire Hao is a San Francisco Chronicle staff writer. Email: [email protected], Twitter: clairehao_
George is Digismak’s reported cum editor with 13 years of experience in Journalism