Insider asked four public-health experts what it would take for them to fully return to their pre-pandemic lifestyles.
Some are holding out for specific COVID-19 case rates or vaccination thresholds.
Others are waiting to hear about fewer cases among their extended social networks.
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It's the question many of us are, somehow, still confused about, more than a year and a half into the pandemic: How do we know when it will be safe to fully return to normal?
Insider asked four public-health experts for their takes - what they would need to see in order to return to a pre-pandemic lifestyle without worry. How will they decide it's time to resume activities like traveling internationally, throwing parties, or attending conferences?
Each said that probably won't happen until at least next year, and will likely depend on whether a new variant arises that could overtake Delta. But the metrics these experts are using to make those decisions vary significantly.
Some are holding out until the US hits a certain vaccination threshold - at least 80% of the population fully vaccinated. Others are waiting until hospitals aren't overwhelmed, or their local COVID-19 rate dips below 10 daily cases per 100,000 people.
But some experts just aren't comfortable relying solely on data anymore. Instead, they're focused on how often they hear about friends and family who've recently been exposed to the virus - an informal sign of how prevalent COVID-19 is in their community.
"We're moving away from a point where you can pinpoint a given number and say, 'We should feel safe,'" Rachael Piltch-Loeb, a fellow at the Harvard T.H. Chan School of Public Health, told Insider. "It becomes much more your perception of risk to yourself, to your family."
Still, the experts offered several tipping points that would facilitate their return to normal.
Chris Beyrer is waiting for higher vaccination rates
Before the Delta variant became dominant, Chris Beyrer had hoped to resume his HIV research in Thailand or South Africa this fall. Beyrer, an epidemiologist at the Johns Hopkins Bloomberg School of Public Health, said he's now waiting to see higher vaccination rates in those countries before visiting.
"International travel to places where vaccine access is low, or uptake is low, is a ways off," Beyrer told Insider. "We will be very fortunate if we're able to do this by late 2022. I think probably mid-2023 is more realistic."
Beyrer estimated that countries will likely need to see vaccination rates above 80% - perhaps 85% or 90% - before Delta infections stop spreading easily. Getting to that number is possible in the US, he said, but it will require patience. (Just 55% of Americans are fully vaccinated right now.)
"I am hopeful that we will start to turn the corner both once we have more mandates in place and we get higher immunization coverage, and once we have approval for the under-12-year-olds," Beyrer said. "That's going to be a big change. Until then, we have to be cautious."
Cindy Prins is looking for low daily cases in her community
Dr. Anthony Fauci recently told Axios that the US needs to see fewer than 10,000 daily COVID-19 cases before the virus no longer poses a public-health threat. Currently, the US is seeing around 140,000 daily cases. But Cindy Prins, an epidemiologist at the University of Florida, is looking at her local case rate, not a national number, to determine when she'll return to indoor restaurants and fitness classes.
"I'd like to see it maybe hit 10 cases per 100,000 population," Prins said. "The likelihood of you encountering someone who actively has COVID at that point becomes a lot lower, so it just makes me feel like the odds are in my favor."
Alachua County, where Prins is located, is currently reporting around 360 cases per 100,000 people.
Like Beyrer, Prins thinks a vaccination target of around 85% would help communities significantly lower transmission. But she cautioned that vaccination metrics "may not show the whole story," since many people have also acquired immunity through infection.
The promise of booster shots doesn't do much to sway her comfort level, she added.
"A third shot would be great, but I don't think a third shot is going to send me back to the activities right away that I consider to be risky," Prins said.
Rachael Piltch-Loeb wants to be sure there's enough hospital capacity
Piltch-Loeb is still avoiding indoor concerts and sports stadiums where there's no vaccination requirement, or where public-health measures like masks and social distancing aren't enforced. To get back to those activities, she said, she needs to feel confident that there are ample hospital beds available where she lives in the Northeast.
That will happen naturally, she added, once more people in her region get vaccinated.
"I'm trying to move away from being hung up on a given case number and really focus on vaccination rates and healthcare capacity to respond to severe infection in my geographic area," Piltch-Loeb said.
She expects masks to become part of her "new normal" on planes and in healthcare facilities.
"There will be new normals for everyone," she said, "but I'm looking to the future with high hopes for 2022."
Ellen Eaton is waiting until her kids can get vaccinated
Data can, of course, can be flawed.
"In the deep South especially, a lot of the dashboards aren't being updated for reasons that are largely political and cultural," Ellen Eaton, an infectious-disease expert at The University of Alabama at Birmingham, told Insider, adding, "a lot of my colleagues and I are really not following our dashboards because we're just not convinced that they are being updated and the data quality is as robust as it was early in the pandemic."
Eaton isn't focused much on vaccination rates, either. The coronavirus doesn't respect borders, she said, and vaccine uptake differs dramatically from county to county.
Instead, she's waiting until her young children can get vaccinated before she'll consider hosting indoor dinner parties with friends or allowing her kids to return to indoor Boy Scout meetings and church services. Then once they get the shots, Eaton said, she'll probably hold off on those activities until she hears about fewer COVID-19 cases in her community.
"When we're hearing about fewer of our friends contracting COVID at similar events, when we're hearing about fewer school children coming home or coming to school with a case of coronavirus, we'll start widening our bubble," she said.