COVID-21 is the product of all these changes in aggregate. It’s the disease as it will be experienced in the months and years to come: with new variants of the virus, new public policies and health behaviors, various degrees of immune memory, and—most important—a cavalcade of new vaccines.

One-quarter of all Americans have now received at least one shot, and that number is racing up. This month, New Yorkers lined up outside Yankee Stadium throughout the night at a makeshift 24/7 vaccination site, until the supply ran out. “If we open 3000 appointments, they will immediately fill,” says Ramon Tallaj, a physician who oversees clinical care in underserved communities across New York City. Demand seems to be growing. If there were sufficient supply, Tallaj told me, his team could be giving out 40000 doses every day. And this should happen soon; the White House says that shortages will end in the coming weeks.

The vaccination effort is sure to change the nature of COVID in unexpected ways. The habitat for the virus is changing: It may still stick in the nasal passages of an immunized person, but it shouldn’t continue on its way into the lungs, much less the toes. The key question is just how long this protection will last, especially against a rapidly mutating virus. Clinical trials have shown the vaccines to be fantastic at preventing serious illness so far, but haven’t yet been able to observe how protection might dissipate over long periods.

And unexpectedly, Covid-19 has proved to be the catalyst. “What the pandemic has done is accelerate the adoption of genomics into infectious disease by several years,” says deSouza, the Illumina chief executive. He also told me he believes that the pandemic has accelerated the adoption of genomics into society more broadly — suggesting that quietly, in the midst of chaos and a global catastrophe, the age of cheap, rapid sequencing has arrived.

Ultrafast and ultracheap sequencing could reshape the future of health care.

A new Covid-19 variant from the Amazon is now responsible for the majority of new infections in Brazil, with many doctors there saying they are seeing more young and otherwise healthy patients falling ill. Hopefully Covid doesnt bounce back and turn into the 1918 flu.

“We’re in the trenches here, fighting a war,” said Andréia Cruz, a 42-year-old emergency-ward nurse in the southern Brazilian city of Porto Alegre. In the past three weeks alone, the surrounding state of Rio Grande do Sul has seen nearly 5000 people die from Covid-19, more than in the final three months of last year.

The spread of the virus in Brazil threatens to turn this country of 213 million into a global public-health hazard. The so-called P.1 strain, present in more than 20 countries and identified in New York last week, is up to 2.2 times more contagious and as much as 61% more able to reinfect people than previous versions of the coronavirus, according to a recent study.

The P.1 is now responsible for the majority of new infections in Brazil, with many doctors here saying they are seeing more young and otherwise healthy patients falling ill. About 30% of people dying from Covid-19 are now under 60, compared with an average of about 26% during Brazil’s previous peak between June and August, according to official figures analyzed by The Wall Street Journal.