To the surprise of many people – including mine – new Covid-19 cases in the US have not started to rise. Over the past two weeks, they have remained roughly stable, declining by about 1 percent, even as the highly contagious BA.2 subvariant of Omicron has become the dominant form of Covid in the US
In contrast, in much of Europe, cases rose sharply last month after BA.2 started spreading there, with many experts expecting a similar pattern here. That didn’t happen. “It hasn’t taken off,” Michael Osterholm, a University of Minnesota epidemiologist, told me.
What is happening? Today’s newsletter looks at four possible explanations.
1. More Immunity
Although the US has a lower vaccination rate than Western Europe, this country may still have built up more immunity – thanks to our politically polarized response to the virus.
In liberal parts of the US, vaccination rates can be even higher than in Europe. In conservative communities, many Americans have demeaned Covid so much that they have been living almost normal lives for a long time. As a result, the virus has already swept through these communities, giving many people at least some immunity.
This laissez-faire approach has had terrible drawbacks. Covid death rates were much higher in counties that voted for Donald Trump than in counties that voted for Joe Biden. But for people who have survived a previous Covid infection, it does offer some immune protection, especially if it was recent.
“Most of Europe is quite averse to Covid,” William Hanage, a Harvard epidemiologist, said in a recent episode of the podcast “In the bubble”, “while parts of the United States were quite Covid-curious.” Hanage said he still expected the number of cases in the US to increase rapidly. But, he added: “I don’t think it will be as dramatic as Europe.”
If that’s true, there’s already a foretaste in the northeast, where the number of cases has been rising recently, but not as steeply as in Europe.
One possible reason: Not many Americans are vulnerable to infection. The earlier version of the Omicron variant appears to have infected about 45 percent of Americans, according to Andy Slavitt, a former Covid adviser at the Biden White House. That share appears to be higher than that of Europe.
2. Less testing
The shift to home testing in recent months means that a smaller proportion of actual Covid cases may show up in the data reported by government agencies and news organizations such as The Times. The government data is based on laboratory tests.
Another possible factor depressing the number of tests is reduced access for lower-income Americans. Some uninsured people now have to pay for their own tests and many testing clinics are closed.
All of this raises the possibility that Covid cases are now really on the rise, even if the data doesn’t show it.
Jessica Malaty Rivera of Boston Children’s Hospital told The Atlantic that the quality of current Covid data was “poor”. dr. Scott Gottlieb, a former FDA commissioner, told CNBC he thought some parts of the country were under-reporting cases.
This chart suggests that underreporting is a real problem. As you can see, official testing in several European countries increased as BA.2 spread, while testing in the US has declined modestly.
Still, the lack of testing doesn’t seem to be the only reason the number of cases hasn’t risen in the US. Trends in Covid hospitalizations are typically only about a week behind trends in cases. And US hospital admissions have continued to fall, to their lowest level in more than two years.
3. Wait a minute
Even if a high level of immunity has prevented the number of cases from increasing so far, the effect may not be permanent. Remember: About 45 percent of Americans were infected with Omicron, leaving about 55 percent were not. While many of those 55 percent may have had a previous version of Covid, immunity may wane over time.
The present moment could be one of those times when we wonder why things don’t start rising the moment they start rising. “It may be too early to see a signal,” Jennifer Nuzzo, a Brown University epidemiologist, told me.
Apr 6, 2022, 10:05 a.m. ET
4. Another mystery
During the pandemic, Osterholm — the Minnesota epidemiologist — has complained that many scientists, journalists and laypeople are exaggerating how much we actually know about Covid. His favorite example: The Alpha variant swept through Michigan and Minnesota last year, then largely died out, without increasing cases in other parts of the US. Another example: BA.2 has recently become the dominant variant in India, South Africa and some other countries without causing a spike in cases†
When I called Osterholm yesterday to ask why there weren’t so many cases in the last few weeks, he simply said, “I don’t know, and I don’t think anyone really knows.”
Of all the variants, only the original Omicron was so contagious that it spread around the world in predictable ways, he said. Other versions of the virus have mysteriously risen and disappeared, just as a forest fire can die out without burning down an entire forest.
It comes down to: It appears that the number of cases in the US will continue to increase rapidly, perhaps significantly. But a new wave seems less certain than a few weeks ago. Regardless, the steps that could save lives in the coming months remain the same: more vaccine shots, including boosters; and greater awareness of available treatments that provide additional protection for the vulnerable.
ART AND IDEAS
Non-glamorous social media
Can a social media platform be “authentic”? Meticulously staged content is commonplace on Instagram and TikTok. BeReal, an app popular among American students, promises the opposite, Bloomberg reports:†
The app, which originated in France, sends a notification at a different time every day. Users have two minutes to take pictures simultaneously using the front and back cameras of their phone. Due to the time limit, the images are often candid and mundane: lecture halls, unfiltered selfies, a takeaway lunch. Users must submit their photos before they can see friends’ posts.
“You don’t exhibit anything to people you only know a little,” a student told The Daily Northwestern† “You’re really just sharing a moment of your day with the people who matter most.”
PLAY, WATCH, EAT
What to cook?
Yesterday’s Spelling Bee pangram was captivity. Here’s today’s puzzle – or you can play online.
Here’s today’s Wordle. Here’s today’s mini crossword and a clue: pie levels (five letters).
If you’re in the mood to play more, you’ll find all our games here.
Thank you for spending part of your morning at The Times. See you tomorrow. — David
Correction: Tuesday’s newsletter stated that the Biden administration has blocked the delivery of S-300 anti-aircraft missile systems to Ukraine. Government officials say they favor the provision of such systems, even though it has not yet happened.
Here is today’s front page†
“The Daily” is about war crimes. “The Argument” features a former top NATO commander.
Claire Moses, Ian Prasad Philbrick, Tom Wright-Piersanti, Ashley Wu and Sanam Yar contributed to The Morning. You can reach the team at: firstname.lastname@example.org†
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SOURCE – www.nytimes.com