Coronavirus Briefing: What Happened Today

U.S.|Coronavirus Briefing: What Happened Today

Watch Pfizer make the vaccine.

Jonathan Wolfe


Credit…The New York Times


Credit…Elliot deBruyn

Vials of plasmids are pulled from the master cell bank, the source of every batch of Pfizer’s Covid-19 vaccine, and thawed. Scientists modify E. coli bacteria to take the plasmids inside their cells. The modified bacteria are moved to a growth medium, then fermented in nutrient broth, multiplying every 20 minutes and making trillions of copies of the DNA plasmids.

Scientists then use a chemical to break up the bacteria and release the plasmids from their enclosing cells.

The plasmids are compared against previous samples to confirm that the coronavirus gene sequence has not changed, then cut with enzymes and filtered, leaving only purified DNA in one-liter bottles. Each bottle will produce about 1.5 million doses.


Credit…The New York Times

Each DNA bottle is frozen and shipped to another Pfizer facility in Andover, Mass., where enzymes transcribe the DNA into messenger RNA, or mRNA. The resulting 16-liter bags of mRNA are tested, frozen and shipped to a Pfizer facility in Kalamazoo, Mich.

Scientists prepare oily lipids to protect the mRNA and help it enter human cells. The lipids and naked strands of mRNA are mixed, and an electric charge pulls them together in a nanosecond, forming an oily, protective vaccine particle.


Credit…Elliot deBruyn

Hundreds of thousands of empty vials are filled at a pace of up to 575 vials per minute. The vaccine is chilled but warms up quickly during the bottling process, and the mRNA will deteriorate if left unfrozen for too long. So Kalamazoo has only about 46 hours to get the liquid vaccine into vials and then into deep freeze.


Credit…The New York Times

The filled vials are packed into small plastic trays called “pizza boxes” with 195 vials each, and then loaded into one of 350 industrial freezers. After weeks of testing, the vaccine is ready to ship.

Pfizer currently operates on a 60-day timeline from start to finish, and more than half of that time is dedicated to testing. Commercial production of the vaccine began in September. As of April 22, the plant had delivered more than 150 million vaccine doses to the United States. Pfizer expects to deliver 220 million doses by the end of May, and 300 million by mid-July.

Watch the entire process here.

Doctors and the media in India are citing anecdotal — and inconclusive — evidence to suggest that a homegrown variant called B.1.617 is driving the country’s terrifying outbreak.

It’s a scary idea, as the presence of the variant could make it more difficult to tame India’s disaster. A number of doctors are also saying that younger people and people who have been fully vaccinated are getting sick.

But researchers outside of India say the limited data so far suggests that the B.1.1.7 variant that walloped Britain late last year may be a more considerable factor. Scientists also say that different variants seem to dominate specific areas. For instance, the B.1.617 variant has been detected in a large number of samples from the central state of Maharashtra, while the B.1.1.7 variant is rising quickly in New Delhi. Ultimately, the data is too thin to parse because India is performing too little genomic sequencing.

Beyond the variants, scientists believe that other, possibly more obvious factors could be to blame: a low vaccination rate, lax public behavior, governmental missteps and a premature reopening of schools and businesses.

More on India:

  • An aunt of Prime Minister Narendra Modi died after contracting the coronavirus.

  • India is allowing people to gather for pilgrimages in Uttarkhand and Kashmir.

  • The Times followed two brothers in India on a hunt for oxygen for their sick father, who was dying from the coronavirus.

  • “I’m sitting in my apartment waiting to catch the disease. That’s what it feels like right now in New Delhi.” The Times’s South Asia bureau chief wrote a personal essay about life at the epicenter of the world’s worst Covid crisis.

  • Here are some ways you can help India amid the crisis.

  • A study found that Pfizer and Moderna vaccines are 94 percent effective at preventing hospitalization in older adults.

  • The European Union secured more vaccine doses from Pfizer with the help of personal diplomacy — including texts and calls from Ursula von der Leyen, the European Commission’s top executive, to Pfizer’s chief executive.

  • Australia prioritized Olympic-bound athletes for vaccines.

  • The governor of Tennessee declared that the coronavirus is no longer a public health emergency, even though only a quarter of people in his state have been vaccinated, CNN reports.

  • Around 70 percent of adults in England now have Covid antibodies, according to the country’s Office for National Statistics, Sky News reports.

Point of view: You’re a teen during 2020-2021. Your school has transformed into a tiny computer screen that only sometimes works. Your grades are as low as they have ever been. You’re not exactly depressed, but also you find yourself crying at the smallest things. Your group texts have been silent for so long and you don’t even know how your friendships will survive this. You’re angry when you see other people hanging out, but also envious of them. You can’t sleep at night and can’t stay awake during the day. You just feel numb.

— Sadie McGraw, Boston

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Jonathan Wolfe