The USDA has now announced that there’s “no credible evidence” that people can get Covid-19 from touching packages in the grocery store. At first blush, this sounds like a breakthrough — but there was no evidence of this in the spring of 2020 either.
Throughout the pandemic, there’s been a tendency to play up unlikely risks, and not to talk enough about uncertainty and probabilities.
The risk of getting Covid-19 from groceries or mail or monkey bars was always a guess. Yes, there was an eye-popping lab experiment last spring that showed that parts of viral RNA — but not necessarily live virus — could persist for a few days on some surfaces. Yet the public was advised to scrub and sterilize everything, even though there was never evidence that groceries posed more than a tiny risk compared to crowded living or working conditions.
Science and science communication are both fraught with the potential for error — what makes them work is honesty and transparency. It’s not that hard to explain the difference between a potential danger that hasn’t been tested and something where there’s evidence piling up that the danger is minuscule. People can grasp that. It’s not rocket science.
But for the past year, there’s been too much spin, too much moralizing, and not enough in the way of clear explanation. People still wrongly fear that passing others on the street is a big danger because scientists and the press lump all risks together — substantial with astronomically unlikely.
Vaccine messaging is now playing up post-vaccination risks, with health authorities saying vaccinated people will have to continue take exactly the same precautions. As Times columnist David Leonhardt found, many people took that recommendation so seriously that they’re questioning the point of getting the shots, or are refusing them.
In fact, having a dinner party with a few vaccinated friends would be reasonable, says Babak Javid, an infectious disease doctor at UCSF. Could someone transmit the disease — maybe? “I think the risks of that are so remotely low,” he says. He would go if invited.
It’s true that even 95% vaccine efficacy means a few people might still get the disease post-vaccination — and some might get a silent case and give it to someone else — but the vaccine is proving close to 100% effective at preventing the most severe and deadly cases. And as more people get vaccinated, incidence of the disease should plunge even lower. The risks will plunge with it.
Why not lay that all out on the table and propose a short period of stringent post-vaccine precautions, to be eased when all the most vulnerable people are vaccinated? With 500,000 people dead, we shouldn’t be focusing on extremely unlikely risks when larger ones loom.
Javid was one of the very first proponents of masking, fighting for it back when it was unpopular with other public health leaders — but even he draws the line at making runners and cyclists or solitary walkers mask up. “In the context of the pandemic where there are literally hundreds of million cases worldwide, even rare events can happen,” he says. “So I am not going to say it is impossible. I think the risks of, you know, someone cycling past you and giving you Covid is minimal, to say the least.”
He says the biggest positive impact of outdoor mask mandates is that it might encourage people to mask up indoors. If that’s the reason, I think officials should be explicit about that so people don’t actually believe their neighbors could infect them from across the street.
Adding to the confusion is the way cumulative cases have gotten muddled with current infection rates. People I know have been frightened by the New York Times reporting that 1 in 8 people in my home state of Rhode Island have been infected. You have to read carefully to see the numbers refer to people who’ve tested positive from the beginning of the pandemic — the vast majority of whom would no longer be infectious today.
That may in part explain why I keep hearing educated people try to tell me that once people contract the disease, they will always be carriers. That’s true for untreated HIV, but SARS-CoV-2 can be cleared, like flu — which people don’t pass on after they’ve recovered. The risk of getting Covid-19 in a given region is related to the percent of people who are actively infectious — a condition that lasts only a few days. But such useful numbers are drowned out by more dramatic sounding ones.
Scientists and journalists may feel magnifying small risks is erring on the side of caution. But if freaking people out about small things is distracting from the risks that have led to most of the 500,000 deaths, then perhaps true caution would instead dictate erring as little as possible.
Bloomberg
