Another coronavirus variant linked to growing share of cases, several large outbreaks, in California

Coroner Elizabeth Napoles, right, of the Los Angeles County Department of Medical Examiner, works with National Guardsmen, helping to store the bodies of covid-19 victims last week. 

Health officials stress they haven’t determined whether the variant might be more contagious or resistant to vaccines.

coronavirus variant first identified in Denmark has ripped through Northern California — including outbreaks at nursing homes, jails and a hospital in the San Jose area — prompting state and local officials to investigate whether it may be more transmissible.

California officials disclosed the rise of the variant Sunday night after genetic monitoring linked it to a fast-growing share of new cases, as well as to the outbreaks in Santa Clara county, which includes San Jose.

This rising variant is distinct from the highly contagious mutation discovered by Britain, which has also been found in California, and which federal health officials project could become the dominant strain in the United States by March based on its proven higher transmissibility.

Experts stress that they need to look more closely at the circumstances of the Northern California outbreaks, as well as at the latest variant — this one, known as L452R — before declaring it more contagious or more dangerous than the virus already broadly circulating.

The L452R variant was first detected in northern Europe in March and has since been confirmed in more than a dozen states, including California in May. The discovery did not garner much attention at the time because all viruses change constantly as they replicate. But public health authorities deem some variants to be “of concern” if evidence suggests they might be more contagious, potentially deadlier or resistant to vaccines.

California publicized the latest variant at a late Sunday news conference after researchers identified it in about 25 percent of samples collected between Dec. 14 and Jan. 3, a surge from 3.8 percent of samples collected in the preceding three-week period.

“That is suggestive, and it’s a little worrisome,” Charles Chiu, a virologist at the University of California at San Francisco said at the briefing. But Chiu stressed it was too early to conclude the variant is more infectious because scientists do not know whether their sampling was representative or whether the variant’s increase might be due to random chance, or even a series of superspreader events.

Officials urged people to follow public health guidelines to minimize the risk of contracting the variant as new daily cases in the hard-hit state plateau at more than 38,000, while deaths average more than 515 daily.

“It’s too soon to know if this variant will spread more rapidly than others,” said Erica Pan, California’s state epidemiologist, “but it certainly reinforces the need for all Californians to wear masks and reduce mixing with people outside their immediate households to help slow the spread of the virus.”

Genetic sequencing of viruses is still limited in the United States, preventing health officials from having a real-time picture of all the strains of coronavirus spreading across the country and their prevalence.

California’s preliminary data is based on fewer than 400 samples that overwhelmingly came from the state’s north. Southern California is the heaviest hit part of the state, with deaths in Los Angeles County reaching one every seven minutes and ICU beds and oxygen running out, although hospitalizations have begun to plateau. Environmental regulators on Sunday temporarily lifted limits on cremations because of a backlog in Los Angeles County.

The L452R strain in California raised alarms because it is associated with several large outbreaks in Santa Clara County, including one at a hospital that infected at least 90 people and killed one staff member. Officials at Kaiser Permanente San Jose Medical Center said a staff member wearing an inflatable Christmas tree costume to spread holiday cheer likely spread coronavirus-laden droplets instead.

A Kaiser Permanente employee died and dozens of others contracted the coronavirus after a staffer appeared at the San Jose medical center wearing an inflatable, air-powered holiday costume on Christmas Day.

Sara Cody, Santa Clara’s top public health official, described that episode as a “very unusual outbreak with a lot of illnesses, and it seemed to spread quite fast.” The county is working with state health officials and the CDC to investigate what happened, she said.

Cody cautioned that the outbreak could have been driven by factors unrelated to the variant, such as changes in ventilation or personal protective equipment practices at the hospital.

“The takeaway is not that we need to start worrying about this,” Cody said Sunday. “The takeaway is, this is a variant that’s becoming more prevalent, and we need to lean in and understand more about it.”

County officials on Monday disclosed other places where the variant had been found as a result of aggressive genetic sequencing, “including cases associated with the Kaiser outbreak, skilled nursing facility outbreaks, cases in jails and shelters, and specimens from testing sites in the community,” according to a statement. “This suggests that the variant is now relatively common in our community.”

Chiu, the virologist who conducted the genetic sequencing, said a deeper investigation must be done to determine if the strain is more transmissible like the one found in the United Kingdom.

He also raised concerns that a mutation associated with the variant might make it more resistant to vaccines because it occurs in a critical part of the spike protein that is targeted by the vaccines,but he added that the virus must be grown in a lab and tested more fully before any conclusions can be drawn.

“Mutations happen all the time,” said William Hanage, an epidemiologist at the Harvard T.H. Chan School of Public Health. “Some of them take off and the great majority of them don’t. The main reason why we are paying attention to this is because this mutation has previously been noted as being of particular concern in terms of diminishing the efficacy of the immune response.”

Carlos del Rio, a professor of medicine and global health at Emory University, said the rising prevalence of the variant shows the urgent need for more genetic sequencing in the United States and for greater compliance with public health measures such as wearing masks and avoiding crowds.

“We really need to hunker down because if you are really concerned about mutations, stop transmission,” del Rio said. “The more mutations you see, the more uncontrolled transmission you will see.”

After starting the new year with record-high cases, deaths and hospitalizations, the United States is starting to see signs of slowing spread despite fears of a post-holiday surge that would continue through January. The seven-day average of new infections has slowed since last Tuesday, and hospitalizations have started to plateau, according to Washington Post tracking.

Still, Scott Gottlieb, a former Food and Drug Administration commissioner, warned that the advent of more transmissible variants could reverse that progress.

“As current epidemic surge peaks, we may see 3-4 weeks of declines in new cases but then new variant will take over,” Gottlieb tweeted Sunday, referring to the British variant. “It’ll double in prevalence about every week. It’ll change the game and could mean we have persistent high infection through spring until we vaccinate enough people.”

The United States could hit half a million covid-19 deaths by mid-February

“It took 12 weeks for the death toll to rise from 200,000 to 300,000. The death toll has leaped from 300,000 to almost 400,000 in less than five weeks,” The Post’s  Marc Fisher, Lori Rozsa, Mark Kreidler and Annie Gowen report. 

Yet despite the massive death toll and the changes to daily life caused by the pandemic, the individual deaths are largely invisible.  

“Coronavirus victims who die in the hospital often spend their final days cut off from family and friends, their only human contact coming from medical personnel hidden behind layers of protective gear. Even those who die at home often decline in quarantine, keeping a lonely vigil over their body’s fight,” my colleagues write.

The numbers are expected to quickly rise. Rochelle Walensky, the incoming director of the Centers for Disease Control and Prevention, told “Face The Nation” on Sunday that she anticipated half a million deaths by mid-February.

“That doesn’t speak to the tens of thousands of people who are living with a yet- uncharacterized syndrome after they’ve recovered. We still yet haven’t yet seen the ramifications from holiday travel, holiday gathering in terms of high rates of hospitalizations,” Walensky added.

Here are six key ways Biden is promising to fight the coronavirus pandemic

By the time President-elect Joe Biden takes the oath of office on Wednesday, more than 400,000 Americans will have died of covid-19 — a dismal milestone in the deadly pandemic.

Yet the crucial task he faces  rapidly distributing coronavirus vaccines to the American public  is one that most experts one year ago didn’t think would even be an option by this point. Few expected multiple vaccines to be approved within a year — a record for vaccine development, by any measure. And although the rollout has been criticized, Israel and Great Britain are the only major nations the United States lags in vaccinations per capita and its daily rate of immunizations has more than doubled in the past two weeks.

“You have my word: We will manage the hell out of this operation,” Biden said in a speech on Friday, announcing his own vaccination plan. 

Regardless of whether one views the vaccine effort up to this point as a failure or success, this much is true: Biden and his new administration will face an enormous task, not only in getting the vaccines distributed but also in ramping up testing, convincing Americans to follow public health recommendations and responding to the economic fallout from the pandemic. 

Here are six key promises Biden is making about his pandemic response:

1. Administer 100 million doses of coronavirus vaccine during the first 100 days of his administration.

Biden previously cited this as a goal. He reiterated it Friday while rolling out a broader plan for coronavirus vaccinations

The plan would require a rate of 1 million immunizations per day — and the United States isn’t too far away from that goal right now. Nearly 800,000 Americans are getting shots every day on average. That’s a considerable improvement from two weeks ago, when the daily rate was closer to 350,000.

The 100-shot goal is “absolutely a doable thing,” Anthony S. Fauci, direct of the National Institute for Allergy and Infectious Disease, told NBC’s Chuck Todd yesterday.

“The feasibility of his goal is absolutely clear; there’s no doubt about it,” Fauci said. “That can be done.”

But top Biden advisers are also cautioning ramping up immunizations will be gradual and will require lots of coordination.

“The first days of that 100 days may be substantially slower than it will be towards the end,” Michael Osterholm, a member of Biden’s covid-19 task force, told Stat News. “It’s not going to occur quickly … you’re going to see the ramp-up occurring only when the resources really begin to flow.”

2. Set up mass vaccination clinics.

By the end of his first month in office, Biden has promised to open 100 federally managed clinics to administer shots. According to his vaccination plan, these sites would be set up by the Federal Emergency Management Agency. The federal government would reimburse states for sending National Guard members to help run them.

Biden says he also wants to deploy mobile units to rural and underserved areas, along with boosting the role already being played by pharmacies in distributing shots. 

This approach would diverge significantly from how things are being done now, with the Trump administration leaving it up to hospitals, doctors, pharmacies and state public health departments to administer the shots. Some cities and states have set up large vaccination sites, but many haven’t.

“Overall, the president-elect’s plan lays out a more muscular federal role than the Trump administration’s approach, which has relied heavily on each state to administer vaccines once the federal government ships them out,” Anne Gearan, Amy Goldstein and Laurie McGinley report.

“Many of the elements — such as seeking to expand the number of vaccination sites and setting up mobile vaccination clinics — were foreshadowed in a radio interview Biden gave last week and in an economic and health ‘relief plan’ he issued Thursday, which contains a $20 billion request of Congress to pay for a stepped-up campaign of mass vaccination,” our colleagues add.

3. Allow federally qualified health centers to directly access vaccines.

These community health centers — which receive higher government reimbursements but are required to accept all patients regardless of their ability to pay — are a core part of the nation’s safety net for low-income Americans.

Biden’s plan proposes a new program “to ensure [federally qualified health centers] can directly access vaccine supply where needed,” although here, too, it’s unclear exactly how that might work.

Under the Trump administration’s plan, these centers have been asked to enroll with state health departments as vaccine providers. States were then supposed to communicate to the federal government how many doses were needed and where they should go.

How well this is actually working is “all over the map,” said Amy Simmons Farber of the National Association of Community Health Centers. She said supplies vary from county to county and many health centers have received their supplies with little notice, making it challenging to prioritize and plan.

Farber declined to comment on the Biden plan, saying she doesn’t have a lot of details about it. But she’s “very encouraged by the recognition of the important role health centers have played in fighting the pandemic and the need to adequately resource them.”

4. Use the Defense Production Act to ensure plenty of vaccine supplies.

Several times over the course of the pandemic, President Trump has invoked the Defense Production Act, which allows the president to require companies to prioritize contracts deemed essential for national security.

Ventilator tubes are attached to a covid-19 patient at Providence Holy Cross Medical Center in Los Angeles. 

He has used the DPA to speed the production of coronavirus tests and ventilators, and to keep meatpacking plants open. But he hasn’t invoked the authority to compel faster production of the supplies needed for packaging and administering the vaccine.

Biden says he will invoke DPA to ensure a steady stream of these supplies, which include glass vials, stoppers, syringes, needles and the capacity for companies to rapidly fill vaccine vials and finish packaging them.

5. Sign executive actions to combat the virus.

Biden has promised a raft of executive actions in his first ten days as president, laid out over the weekend in a memo from incoming White House Chief of Staff Ron Klain. They’ll include a number of pandemic-related orders.

On Inauguration Day, Biden intends to issue a mask mandate on federal property and for interstate travel, while encouraging all Americans to wear masks for what he’s calling a “100 Day Masking Challenge.”

The following day, Thursday, he’ll sign executive orders aimed at helping schools and businesses reopen safely, expanding testing, protecting workers and establishing clearer public health standards. And on Friday, Biden will direct his Cabinet secretaries to take immediate action to deliver economic relief to families.

“President-elect Biden will take action — not just to reverse the gravest damages of the Trump administration — but also to start moving our country forward,” Klain wrote.

6. Launch a vaccine education campaign.

The memo says Biden will run a “federally-run, locally-focused public education campaign.”

“The campaign will work to elevate trusted local voices and outline the historic efforts to deliver a safe and effective vaccine as part of a national strategy for beating covid-19,” it says.

But the transition team hasn’t detailed how the education campaign might differ from one launched by the Trump administration last month. 

The Department of Health and Human Services said it plans to spend $250 million on efforts to promote vaccine awareness. It kicked off the effort with a $150,000 buy on YouTube for ads that feature Fauci and Food and Drug Administration Commissioner Stephen Hahn. 

Vaccine reserve was exhausted when Trump administration vowed to release it, dashing hopes of expanded access

https://www.washingtonpost.com/health/2021/01/15/trump-vaccine-reserve-used-up/

Eric Feigl-Ding on Twitter: "BREAKING—We are out of vaccine reserves! Trump  HHS Sec Azar announced this week that the govt would begin releasing  #COVID19 vaccine doses held in reserve for 2nd shots—but

States were anticipating a windfall after federal officials said they would stop holding back second doses. But the approach had already changed, and no stockpile exists.

When Health and Human Services Secretary Alex Azar announced this week that the federal government would begin releasing coronavirus vaccine doses that had been held in reserve for second shots, no such reserve existed, according to state and federal officials briefed on distribution plans. The Trump administration had already begun shipping out what was available, starting at the end of December, taking second doses for the two-dose regimen directly off the manufacturing line.

Now, health officials across the country who had anticipated their extremely limited vaccine supply as much as doubling beginning next week are confronting the reality that their allocations will remain largely flat, dashing hopes of dramatically expanding access for millions of elderly people and those with high-risk medical conditions. Health officials in some cities and states were informed in recent days about the reality of the situation, while others were still in the dark Friday.

Because both of the vaccines authorized for emergency use in the United States are two-dose regimens, the Trump administration’s initial policy was to hold back second doses to protect against manufacturing disruptions. But that approach shifted in recent weeks, according to the officials, who spoke on the condition of anonymity because they were not authorized to discuss the matter.

Operation Warp Speed, which is overseeing vaccine distribution, stopped stockpiling second doses of the Pfizer-BioNTech vaccine at the end of last year, those officials were told. Shipping of the last reserve doses of Moderna’s supply, meanwhile, began over the weekend.

The shift, in both cases, had to do with increased confidence in the supply chain, so Operation Warp Speed leaders felt they could reliably anticipate the availability of doses for booster shots — required three weeks later in the case of the Pfizer-BioNTech product and four weeks later under Moderna’s protocol.

But it also meant there was no stockpile of second doses waiting to be shipped, as Trump administration officials suggested this week. Azar, at a briefing Tuesday, said, “Because we now have a consistent pace of production, we can now ship all of the doses that had been held in physical reserve.” He explained the decision as part of the “next phase” of the nation’s vaccination campaign.

Those in line for their second shots are still expected to get them on schedule because second doses are prioritized over first shots and states are still receiving regular vaccine shipments. But state and local officials say they are angry and bewildered by the shifting directions and changing explanations about supply. Their anxiety was deepened by projections that a highly contagious virus variant would spread rapidly throughout the United States and as daily covid-19 deaths averaged 3,320 this week.

The health director in Oregon, Patrick M. Allen, was so disturbed that he wrote Azar on Thursday demanding an explanation. In his letter, he recounted how Gustave F. Perna, the chief operating officer of Operation Warp Speed, had “informed us there is no reserve of doses, and we are already receiving the full allocation of vaccines.”

“If true, this is extremely disturbing, and puts our plans to expand eligibility at grave risk,” Allen wrote. “Those plans were made on the basis of reliance on your statement about ‘releasing the entire supply’ you have in reserve. If this information is accurate, we will be unable to begin vaccinating our vulnerable seniors on Jan. 23, as planned.”

HHS spokesman Michael Pratt confirmed in an email that the final reserve of second doses had recently been released to states but did not address Azar’s comments, saying only, “Operation Warp Speed has been monitoring manufacturing closely, and always intended to transition from holding second doses in reserve as manufacturing stabilizes and we gained confidence in the ability for a consistent flow of vaccines.”

But the explanations by the federal government were conflicting. The 13 million doses made available for states to order this week — for delivery next week — represented “millions more” than in previous weeks, Pratt said. He also said states have not requested the full amount they have been allocated.

Guidance circulated Friday among HHS officials acknowledged, however, that “the notion that there is a large bolus of second doses that will be released to jurisdictions is not accurate.” And state and municipal health officials said their allocations for next week had increased only marginally, if at all.

Chicago Public Health Commissioner Allison Arwady said her city’s share had gone from about 32,000 doses to 34,000 doses. “I have stopped paying a whole lot of attention to what is being said verbally at the federal level right now,” she said.

Nirav Shah, the director of Maine’s Center for Disease Control and Prevention, said he learned only Friday, by calling his state’s designated contact at Warp Speed, that the reserve no longer existed.

Maine still plans to broaden vaccination next week to those 70 and older. “Who is in line will not change,” Shah said. “The velocity of that line will change because this bolus of doses that we intuited was coming based on Azar’s comments is not coming.”

In an email that reached some state officials Friday morning, Christopher Sharpsten, an Operation Warp Speed director, called it a “false rumor” that “the federal government was holding back vaccine doses in warehouses to guarantee a second/booster dose.”

In fact, that information had come fromAzar, who said Tuesday that the “next phase” of the country’s vaccination campaign involved “releasing the entire supply we have for order by states, rather than holding second doses in physical reserve.”

Azar’s comments Tuesday followed a Jan. 8 announcement by President-elect Joe Biden’s transition team that his administration would move to release all available doses rather than holding half in reserve for booster shots. Biden’s advisers said the move would be a way to accelerate distribution of the vaccine, which is in short supply across the country.

Azar initially said the Biden plan was shortsighted and potentially unethical in putting people at risk of missing their booster shots. When he embraced the change four days later, however, he did not say that the original policy had already been phased out or that the stockpile had been exhausted. Trump administration officials and Biden’s team alike have sought to reassure the public that increasing the pace of immunizations would not endanger booster shots.

Azar also signaled to states that they would soon see expanded supply, urging them to begin vaccinating adults 65 and older and those under 64 with high-risk medical conditions. Officials in some states embraced that directive, while others said that suddenly putting hundreds of thousands of additional people at the front of the line would overwhelm their capacity.

In subsequent conversations with state and local authorities, federal officials sought to temper those instructions, said people who participated in the conversations. Perna, for instance, spoke directly to officials in at least two of the jurisdictions receiving vaccine supply, explaining that allocations would not increase and that they did not have to broaden eligibility as they had previously been told, according to a health official who was not authorized to discuss the matter.

The revised instructions led some state and local officials to hold off on changes. One state health official noted that the updated eligibility guidance announced Tuesday did not appear on the website of the CDC, even though it was stated as federal policy by Azar and by Robert R. Redfield, the CDC director, in their remarks. Under the original recommendations, adults 65 and older and front-line essential workers were to comprise the second priority group, known as Phase 1b, after medical workers and residents and staffers of long-term-care facilities.

There was additional confusion from another change Azar announced this week — making allocation of doses dependent on how quickly states administer them. He originally said that would not take effect for two weeks.

But Connecticut Gov. Ned Lamont (D) on Thursday tweeted that federal officials had notified him that the state would receive an additional 50,000 doses next week “as a reward for being among the fastest states” to get shots into arms. West Virginia, meanwhile, which is moving at the fastest clip, according to CDC data, did not get any additional doses, said Holli Nelson, a spokeswoman for the state’s National Guard.

In a sign that the incentive structure may not be long-lived, a senior Biden transition official, speaking on the condition of anonymity to address ongoing deliberations, said this week that the team did not look kindly on a system that “punishes states.”

Biden has said he wants to see 100 million shots administered within his first 100 days — an aim that will depend on quickly accelerating the pace of immunization. Together, Pfizer and Moderna have agreed to sell 200 million doses to the United States by the end of March, which is enough to fully vaccinate 100 million people.

2 months to slow the new spread

How does coronavirus spread: Community spread and COVID-19

🚨New CDC warning: The highly contagious variant B.1.1.7 originally detected in the U.K. could become the dominant strain in the U.S. by March.

Why it matters: The variant is estimated to be 30% to 50% more transmissible than other forms of the virus, threatening efforts to push the U.S. past its record high case count.

  • The variant is in 12 states, but has been diagnosed in only 76 of the 23 million U.S. cases reported to date, the AP reports.
  • It’s likely that the variant is more widespread than currently reported.

The big picture: Americans are exhausted and burned out, and COVID wariness is slipping.

  • So far, the variants do not appear to be resistant to the existing vaccines or cause more severe disease.
  • But the health care system is on the brink in places like Southern California.
  • Another spike in cases could lead us to a very dark place.

The bottom line: There’s no evidence that this variant is transmitted differently, so keep up the masks and social distancing.

Go deeper … The coronavirus variants: What you need to know.

mRNA Technology Gave Us the First COVID-19 Vaccines. It Could Also Upend the Drug Industry

https://time.com/5927342/mrna-covid-vaccine/?fbclid=IwAR1wC2ZhNbrGepu9WiPIsYMFWwA_VNgwppCQQCwzb_wQYt4EXBNF3wd2s40

How mRNA Technology Gave Us the First COVID-19 Vaccines | Time

“No!” The doctor snapped. “Look at me!”

I had been staring her in the eyes, as she had ordered, but when a doctor on my other side began jabbing me with a needle, I started to turn my head. “Don’t look at it,” the first doctor said. I obeyed.

This was in early August in New Orleans, where I had signed up to be a participant in the clinical trial for the Pfizer-BioNTech COVID-19 vaccine. It was a blind study, which meant I was not supposed to know whether I had gotten the placebo or the real vaccine. I asked the doctor if I would really been able to tell by looking at the syringe. “Probably not,” she answered, “but we want to be careful. This is very important to get right.”

I became a vaccine guinea pig because, in addition to wanting to be useful, I had a deep interest in the wondrous new roles now being played by RNA, the genetic material that is at the heart of new types of vaccines, cancer treatments and gene-editing tools. I was writing a book on the Berkeley biochemist Jennifer Doudna. She was a pioneer in determining the structure of RNA, which helped her and her doctoral adviser figure out how it could be the origin of all life on this planet. Then she and a colleague invented an RNA-guided gene-editing tool, which won them the 2020 Nobel Prize in Chemistry.

The tool is based on a system that bacteria use to fight viruses. Bacteria develop clustered repeated sequences in their DNA, known as CRISPRs, that can remember dangerous viruses and then deploy RNA-guided scissors to destroy them. In other words, it’s an immune system that can adapt itself to fight each new wave of viruses—just what we humans need. Now, with the recently approved Pfizer-BioNTech vaccine and a similar one from Moderna being slowly rolled out across the U.S. and Europe, RNA has been deployed to make a whole new type of vaccine that will, when it reaches enough people, change the course of the pandemic.

Drs. Ugur Sahin and Ozlem Tureci, Co-founders, BioNTech. In January 2020, before many in the Western world were paying attention to a new virus spreading in China, Dr. Ugur Sahin was convinced it would spur a pandemic. Sahin, who in 2008 co-founded the German biotech company BioNTech with his wife Dr. Ozlem Tureci, went to work on a vaccine and by March called his contact at Pfizer, a much larger pharmaceutical company with which BioNTech had previously worked on an influenza vaccine using mRNA. Less than a year later, the Pfizer-BioNTech COVID-19 vaccine became the first ever mRNA vaccine available for widespread use. Even so, Sahin, BioNTech’s CEO, and Tureci, its chief medical officer, maintain that BioNTech is not an mRNA company but rather an immunotherapy company. Much of the couple’s work—both at BioNTech and at their previous venture, Ganymed—has focused on treating cancer. But it is mRNA, and the COVID-19 vaccine made possible by the technology, that has pushed the famously hardworking couple into the ­limelight—and helped them become one of the richest pairs in Germany, though they reportedly still bicycle to work and live in a modest apartment near their office.

Up until last year, vaccines had not changed very much, at least in concept, for more than two centuries. Most have been modeled on the discovery made in 1796 by the English doctor Edward Jenner, who noticed that many milkmaids were immune to smallpox. They had all been infected by a form of pox that afflicts cows but is relatively harmless to humans, and Jenner surmised that the cowpox had given them immunity to smallpox. So he took some pus from a cowpox blister, rubbed it into scratches he made in the arm of his gardener’s 8-year-old son and then (this was in the days before bioethics panels) exposed the kid to smallpox. He didn’t become ill.

Before then, inoculations were done by giving patients a small dose of the actual smallpox virus, hoping that they would get a mild case and then be immune. Jenner’s great advance was to use a related but relatively harmless virus. Ever since, vaccinations have been based on the idea of exposing a patient to a safe facsimile of a dangerous virus or other germ. This is intended to kick the person’s adaptive immune system into gear. When it works, the body produces antibodies that will, sometimes for many years, fend off any infection if the real germ attacks.

One approach is to inject a safely weakened version of the virus. These can be good teachers, because they look very much like the real thing. The body responds by making antibodies for fighting them, and the immunity can last a lifetime. Albert Sabin used this approach for the oral polio vaccine in the 1950s, and that’s the way we now fend off measles, mumps, rubella and chicken pox.

At the same time Sabin was trying to develop a vaccine based on a weakened polio virus, Jonas Salk succeeded with a safer approach: using a killed or inactivated virus. This type of vaccine can still teach a person’s immune system how to fight off the live virus but is less likely to cause serious side effects. Two Chinese companies, Sinopharm and Sinovac, have used this approach to develop vaccines for COVID-19 that are now in limited use in China, the UAE and Indonesia.

Another traditional approach is to inject a subunit of the virus, such as one of the proteins that are on the virus’s coat. The immune system will then remember these, allowing the body to mount a quick and robust response when it encounters the actual virus. The vaccine against the hepatitis B virus, for example, works this way. Using only a fragment of the virus means that they are safer to inject into a patient and easier to produce, but they are often not as good at producing long-term immunity. The Maryland-based biotech Novavax is in late-stage clinical trials for a COVID-19 vaccine using this approach, and it is the basis for one of the two vaccines already being rolled out in Russia.

The plague year of 2020 will be remembered as the time when these traditional vaccines were supplanted by something fundamentally new: genetic vaccines, which deliver a gene or piece of genetic code into human cells. The genetic instructions then cause the cells to produce, on their own, safe components of the target virus in order to stimulate the patient’s immune system.

For SARS-CoV-2—the virus that causes COVID-19—the target component is its spike protein, which studs the outer envelope of the virus and enables it to infiltrate human cells. One method for doing this is by inserting the desired gene, using a technique known as recombinant DNA, into a harmless virus that can deliver the gene into human cells. To make a COVID vaccine, a gene that contains instructions for building part of a coronavirus spike protein is edited into the DNA of a weakened virus like an adenovirus, which can cause the common cold. The idea is that the re-engineered adenovirus will worm its way into human cells, where the new gene will cause the cells to make lots of these spike proteins. As a result, the person’s immune system will be primed to respond rapidly if the real coronavirus strikes.

This approach led to one of the earliest COVID vaccine candidates, developed at the aptly named Jenner Institute of the University of Oxford. Scientists there engineered the spike-protein gene into an adenovirus that causes the common cold in chimpanzees, but is relatively harmless in humans.

The lead researcher at Oxford is Sarah Gilbert. She worked on developing a vaccine for Middle East respiratory syndrome (MERS) using the same chimp adenovirus. That epidemic waned before her vaccine could be deployed, but it gave her a head start when COVID-19 struck. She already knew that the chimp adenovirus had successfully delivered into humans the gene for the spike protein of MERS. As soon as the Chinese published the genetic sequence of the new coronavirus in January 2020, she began engineering its spike-protein gene into the chimp virus, waking each day at 4 a.m.

Her 21-year-old triplets, all of whom were studying biochemistry, volunteered to be early testers, getting the vaccine and seeing if they developed the desired antibodies. (They did.) Trials in monkeys conducted at a Montana primate center in March also produced promising results.

Bill Gates, whose foundation provided much of the funding, pushed Oxford to team up with a major company that could test, manufacture and distribute the vaccine. So Oxford forged a partnership with AstraZeneca, the British-Swedish pharmaceutical company. Unfortunately, the clinical trials turned out to be sloppy, with the wrong doses given to some participants, which led to delays. Britain authorized it for emergency use at the end of December, and the U.S. is likely to do so in the next two months.

Johnson & Johnson is testing a similar vaccine that uses a human adenovirus, rather than a chimpanzee one, as the delivery mechanism to carry a gene that codes for making part of the spike protein. It’s a method that has shown promise in the past, but it could have the disadvantage that humans who have already been exposed to that adenovirus may have some immunity to it. Results from its clinical trial are expected later this month.

In addition, two other vaccines based on genetically engineered adenoviruses are now in limited distribution: one made by CanSino Biologics and being used on the military in China and another named Sputnik V from the Russian ministry of health.

There is another way to get genetic material into a human cell and cause it to produce the components of a dangerous virus, such as the spike proteins, that can stimulate the immune system. Instead of engineering the gene for the component into an adenovirus, you can simply inject the genetic code for the component into humans as DNA or RNA.

Let’s start with DNA vaccines. Researchers at Inovio Pharmaceuticals and a handful of other companies in 2020 created a little circle of DNA that coded for parts of the coronavirus spike protein. The idea was that if it could get inside the nucleus of a cell, the DNA could very efficiently churn out instructions for the production of the spike-protein parts, which serve to train the immune system to react to the real thing.

The big challenge facing a DNA vaccine is delivery. How can you get the little ring of DNA not only into a human cell but into the nucleus of the cell? Injecting a lot of the DNA vaccine into a patient’s arm will cause some of the DNA to get into cells, but it’s not very efficient.

Some of the developers of DNA vaccines, including Inovio, tried to facilitate the delivery into human cells through a method called electroporation, which delivers electrical shock pulses to the patient at the site of the injection. That opens pores in the cell membranes and allows the DNA to get in. The electric pulse guns have lots of tiny needles and are unnerving to behold. It’s not hard to see why this technique is unpopular, especially with those on the receiving end. So far, no easy and reliable delivery mechanism has been developed for getting DNA vaccines into the nucleus of human cells.

That leads us to the molecule that has proven victorious in the COVID vaccine race and deserves the title of TIME magazine’s Molecule of the Year: RNA. Its sibling DNA is more famous. But like many famous siblings, DNA doesn’t do much work. It mainly stays bunkered down in the nucleus of our cells, protecting the information it encodes. RNA, on the other hand, actually goes out and gets things done. The genes encoded by our DNA are transcribed into snippets of RNA that venture out from the nucleus of our cells into the protein-manufacturing region. There, this messenger RNA (mRNA) oversees the assembly of the specified protein. In other words, instead of just sitting at home curating information, it makes real products.

Scientists including Sydney Brenner at Cambridge and James Watson at Harvard first identified and isolated mRNA molecules in 1961. But it was hard to harness them to do our bidding, because the body’s immune system often destroyed the mRNA that researchers engineered and attempted to introduce into the body. Then in 2005, a pair of researchers at the University of Pennsylvania, Katalin Kariko and Drew Weissman, showed how to tweak a synthetic mRNA molecule so it could get into human cells without being attacked by the body’s immune system.

Stéphane Bancel, CEO, Moderna. Moderna’s COVID-19 vaccine was first tested in humans less than three months after news of the novel virus broke. But that lightning-fast development process belies the years of work that got Moderna to where it is today. The startup was founded in 2010 with the belief that mRNA technology, then still fairly new, could help treat any number of ailments. CEO Stéphane Bancel, pictured above, joined a year later. Moderna wasn’t originally focused on vaccines, but over time, its scientists began working toward vaccines against several infectious diseases as well as some forms of cancer. That experience came in handy when the COVID-19 pandemic arrived, leaving the world clamoring for a vaccine that could fight the deadly virus—and fast. Bancel’s company took the challenge in stride, using its mRNA platform to develop a vaccine around 95% effective at protecting against COVID-19 disease in less than a year.

When the COVID-19 pandemic hit a year ago, two innovative young pharmaceutical companies decided to try to harness this role played by messenger RNA: the German company BioNTech, which formed a partnership with the U.S. company Pfizer; and Moderna, based in Cambridge, Mass. Their mission was to engineer messenger RNA carrying the code letters to make part of the coronavirus spike protein—a string that begins CCUCGGCGGGCA … —and to deploy it in human cells.

BioNTech was founded in 2008 by the husband-and-wife team of Ugur Sahin and Ozlem Tureci, who met when they were training to be doctors in Germany in the early 1990s. Both were from Turkish immigrant families, and they shared a passion for medical research, so much so that they spent part of their wedding day working in the lab. They founded BioNTech with the goal of creating therapies that stimulate the immune system to fight cancerous cells. It also soon became a leader in devising medicines that use mRNA in vaccines against viruses.

In January 2020, Sahin read an article in the medical journal Lancet about a new coronavirus in China. After discussing it with his wife over breakfast, he sent an email to the other members of the BioNTech board saying that it was wrong to believe that this virus would come and go as easily as MERS and SARS. “This time it is different,” he told them.

BioNTech launched a crash project to devise a vaccine based on RNA sequences, which Sahin was able to write within days, that would cause human cells to make versions of the coronavirus’s spike protein. Once it looked promising, Sahin called Kathrin Jansen, the head of vaccine research and development at Pfizer. The two companies had been working together since 2018 to develop flu vaccines using mRNA technology, and he asked her whether Pfizer would want to enter a similar partnership for a COVID vaccine. “I was just about to call you and propose the same thing,” Jansen replied. The deal was signed in March.

By then, a similar mRNA vaccine was being developed by Moderna, a much smaller company with only 800 employees. Its chair and co-founder, Noubar Afeyan, a Beirut-born Armenian who immigrated to the U.S., had become fascinated by mRNA in 2010, when he heard a pitch from a group of Harvard and MIT researchers. Together they formed Moderna, which initially focused on using mRNA to try to develop personalized cancer treatments, but soon began experimenting with using the technique to make vaccines against viruses.

In January 2020, Afeyan took one of his daughters to a restaurant near his office in Cambridge to celebrate her birthday. In the middle of the meal, he got an urgent text message from the CEO of his company, Stéphane Bancel, in Switzerland. So he rushed outside in the freezing temperature, forgetting to grab his coat, to call him back.

Bancel said that he wanted to launch a project to use mRNA to attempt a vaccine against the new coronavirus. At that point, Moderna had more than 20 drugs in development but none had even reached the final stage of clinical trials. Nevertheless, Afeyan instantly authorized him to start work. “Don’t worry about the board,” he said. “Just get moving.” Lacking Pfizer’s resources, Moderna had to depend on funding from the U.S. government. Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases, was supportive. “Go for it,” he declared. “Whatever it costs, don’t worry about it.”

It took Bancel and his Moderna team only two days to create the RNA sequences that would produce the spike protein, and 41 days later, it shipped the first box of vials to the National Institutes of Health to begin early trials. Afeyan keeps a picture of that box on his cell phone.

An mRNA vaccine has certain advantages over a DNA vaccine, which has to use a re-engineered virus or other delivery mechanism to make it through the membrane that protects the nucleus of a cell. The RNA does not need to get into the nucleus. It simply needs to be delivered into the more-accessible outer region of cells, the cytoplasm, which is where proteins are constructed.

The Pfizer-BioNTech and Moderna vaccines do so by encapsulating the mRNA in tiny oily capsules, known as lipid nanoparticles. Moderna had been working for 10 years to improve its nanoparticles. This gave it one advantage over Pfizer-BioNTech: its particles were more stable and did not have to be stored at extremely low temperatures.

Katalin Kariko, Senior vice president, BioNTech. In 1995, after years of struggle, Hungarian-born Katalin Kariko was pushed off the path to full professorship at the University of Pennsylvania. Her work on mRNA, molecules she believed could fundamentally change the way humans treat disease, had stalled. Then, in 1997, she met and began working with immunologist Drew Weissman. In 2005, they published a study describing a modified form of artificial ­mRNA—a discovery, they argued, that opened the door to mRNA’s use in vaccines and other therapies. Eventually, Kariko and Weissman licensed their technology to the German company BioNTech, where Kariko, shown here in a portrait shot by a photographer working remotely, is now a senior vice president. Her patience paid off this year. The mRNA-based Pfizer-­BioNTech corona­virus vaccine, which Kariko helped develop, has been shown to be 95% effective at preventing COVID-19.
Katalin Kariko, Senior vice president, BioNTech. In 1995, after years of struggle, Hungarian-born Katalin Kariko was pushed off the path to full professorship at the University of Pennsylvania. Her work on mRNA, molecules she believed could fundamentally change the way humans treat disease, had stalled. Then, in 1997, she met and began working with immunologist Drew Weissman. In 2005, they published a study describing a modified form of artificial ­mRNA—a discovery, they argued, that opened the door to mRNA’s use in vaccines and other therapies. Eventually, Kariko and Weissman licensed their technology to the German company BioNTech, where Kariko, shown here in a portrait shot by a photographer working remotely, is now a senior vice president. Her patience paid off this year. The mRNA-based Pfizer-­BioNTech corona­virus vaccine, which Kariko helped develop, has been shown to be 95% effective at preventing COVID-19.

By November, the results of the Pfizer-BioNTech and Moderna late-stage trials came back with resounding findings: both vaccines were more than 90% effective. A few weeks later, with COVID-19 once again surging throughout much of the world, they received emergency authorization from the U.S. Food and Drug Administration and became the vanguard of the biotech effort to beat back the pandemic.

The ability to code messenger RNA to do our bidding will transform medicine. As with the COVID vaccines, we can instruct mRNA to cause our cells to make antigens—molecules that stimulate our immune system—that could protect us against many viruses, bacteria, or other pathogens that cause infectious disease. In addition, mRNA could in the future be used, as BioNTech and Moderna are pioneering, to fight cancer. Harnessing a process called immunotherapy, the mRNA can be coded to produce molecules that will cause the body’s immune system to identify and kill cancer cells.

RNA can also be engineered, as Jennifer Doudna and others discovered, to target genes for editing. Using the CRISPR system adapted from bacteria, RNA can guide scissors-like enzymes to specific sequences of DNA in order to eliminate or edit a gene. This technique has already been used in trials to cure sickle cell anemia. Now it is also being used in the war against COVID. Doudna and others have created RNA-guided enzymes that can directly detect SARS-CoV-2 and eventually could be used to destroy it.

More controversially, CRISPR could be used to create “designer babies” with inheritable genetic changes. In 2018, a young Chinese doctor used CRISPR to engineer twin girls so they did not have the receptor for the virus that causes AIDS. There was an immediate outburst of awe and then shock. The doctor was denounced, and there were calls for an international moratorium on inheritable gene edits. But in the wake of the pandemic, RNA-guided genetic editing to make our species less receptive to viruses may someday begin to seem more acceptable.

Throughout human history, we have been subjected to wave after wave of viral and bacterial plagues. One of the earliest known was the Babylon flu epidemic around 1200 B.C. The plague of Athens in 429 B.C. killed close to 100,000 people, the Antonine plague in the 2nd century killed 5 million, the plague of Justinian in the 6th century killed 50 million, and the Black Death of the 14th century took almost 200 million lives, close to half of Europe’s population.

The COVID-19 pandemic that killed more than 1.8 million people in 2020 will not be the final plague. However, thanks to the new RNA technology, our defenses against most future plagues are likely to be immensely faster and more effective. As new viruses come along, or as the current coronavirus mutates, researchers can quickly recode a vaccine’s mRNA to target the new threats. “It was a bad day for viruses,” Moderna’s chair Afeyan says about the Sunday when he got the first word of his company’s clinical trial results. “There was a sudden shift in the evolutionary balance between what human technology can do and what viruses can do. We may never have a pandemic again.”

The invention of easily reprogrammable RNA vaccines was a lightning-fast triumph of human ingenuity, but it was based on decades of curiosity-driven research into one of the most fundamental aspects of life on planet earth: how genes are transcribed into RNA that tell cells what proteins to assemble. Likewise, CRISPR gene-editing technology came from understanding the way that bacteria use snippets of RNA to guide enzymes to destroy viruses. Great inventions come from understanding basic science. Nature is beautiful that way.

CDC warns highly transmissible coronavirus variant to become dominant in U.S.

The highly contagious variant of the coronavirus first seen in the United Kingdom will become the dominant strain in the United States within about two months, its rapid spread heightening the urgency of getting people vaccinated, the Centers for Disease Control and Prevention predicted Friday in its most sobering warning yet about mutations in the virus.

In every scenario explored by the CDC, the U.K. strain, which British researchers estimate is roughly 50 percent more transmissible than the more common coronavirus strain, will account for a majority of cases in the United States by some point in March.

The CDC released modeling data to back up its forecast showing a rapid spike in infections linked to the U.K. strain. The agency said the emergence of these mutation-laden variants requires greater efforts to limit viral spread — immediately, even before the U.K. variant becomes commonplace.

So far, no variant is known to cause more severe illness, although more infections would inevitably mean a higher death toll overall, as the CDC made clear in an informational graphic released Friday: “MORE SPREAD — MORE CASES — MORE DEATHS,” it said.

The CDC report “speaks to the urgency of getting vaccines out. It’s now a race against the virus,” said William Hanage, an epidemiologist at the Harvard T.H. Chan School of Public Health.

Scientists both in and out of government have stressed the need for the public to stick to proven methods of limiting viral spread, such as wearing a mask, social distancing, avoiding crowds and having good hand hygiene.

“We know what works and what to do,” CDC scientist Jay Butler said Friday.

The emergence of highly contagious variants has grabbed the full attention of scientists, who in recent weeks have warned that these mutations require closer surveillance. The CDC and its partners in private and academic laboratories are ramping up genomic sequencing efforts to gain better awareness of what is already circulating. Experts think there could be many variants containing mutations worth a closer look.

“This is a situation of concern. We are increasing our surveillance of emerging variants. This virus sometimes surprises us,” Butler said.

Mutations could limit the efficacy of vaccines or therapeutic drugs such as monoclonal antibodies. Scientists believe vaccines will probably remain effective because they produce a robust immune system response, but such reassurances have been paired with cautionary notes about how much remains unknown.

The coronavirus mutations are not unexpected, because all viruses mutate. There are now several “variants of concern” receiving close scrutiny, including ones identified first in South Africa and Brazil, and U.S. officials have said genomic surveillance is still ramping up here and that there may be other variants in circulation, not yet identified, that are enhancing transmission.

“We’re going forward with the assumption that these three variants that we know about now are not going to be the only variants that emerge that are of concern to us,” Greg Armstrong, head of the CDC’s strain surveillance program, said Friday.

The CDC model suggests that the level of pain and suffering in March, when the new variant is expected to be dominant, depends on actions taken today to try to drive down infection rates. Because the threshold for herd immunity depends in part on how infectious a virus is, the emergence of a more transmissible strain can prolong efforts to crush a pandemic.

The emergence in recent weeks of mutation-laden variants has alarmed the CDC and the scientific community because of accelerating infections in Britain, Denmark, Ireland and other countries where the variant named B.1.1.7 has been spreading.

“Increased SARS-CoV-2 transmission might threaten strained healthcare resources, require extended and more rigorous implementation of public health strategies, and increase the percentage of population immunity required for pandemic control,” the CDC wrote. “Taking measures to reduce transmission now can lessen the potential impact of B.1.1.7 and allow critical time to increase vaccination coverage.”

It is unclear if the winter surge in the United States is at a peak, but the numbers are staggering, with more than 200,000 new infections confirmed every day on average.

This is not the first warning from the CDC about variants of the virus, but it is the first to offer a plausible timeline for when and to what degree the mutations seen recently could complicate efforts to end the pandemic.

It shows that vaccination, performed rapidly, is critical to crushing the curve of viral infections. Without vaccines, under one CDC scenario, the country could be dealing with even greater levels of infections in May than in January.

But if public health agencies can ramp up to 1 million vaccinations a day, the CDC model forecasts that daily new infections will decline in the next few months — even with the extra boost from the highly contagious U.K. variant. It has been identified in 12 states, the CDC said Friday, and the agency has informed officials nationwide that they should assume the variant is present in their state.

The CDC and unaffiliated scientists have said they see no evidence that this particular variant is driving the winter surge in cases. So far, it has been involved in fewer than 0.5 percent of infections nationwide, testing data suggests.

Friday’s sobering CDC forecast is based on simple models and has limitations, the agency acknowledged.

The model looks at just the B.1.1.7 variant and does not consider the impact of other variants already discovered or not yet identified. The variants in South Africa and Brazil could prove to be even more problematic, though they have not been spotted so far in the United States. Researchers have noted the disastrous spike in cases in Manaus, Brazil, in recent weeks, despite the high percentage of the population believed to have been previously infected — a situation that raises suspicions, not confirmed by data, that some people who had recovered are becoming re-infected by the new strain.

The CDC model treats the country as a single unit even though the virus is spreading at different rates locally and regionally. No one knows, even at the national level, the current “R,” the reproduction number, of the common coronavirus variant. That’s the number of people an infected person will infect, on average.

The CDC model used plausible reproduction rates of 1.1 (faster spread right now) and 0.9 (slower). The CDC then used British data to project that the U.K. variant is 50 percent more transmissible than the common variant. The model assumes that between 10 and 30 percent of the population has been infected already and recovered and now has immunity.

“It would be foolish to say that this is never going to end, and we might as well stop trying,” the CDC’s Butler said Friday. “But there is reason to be concerned. We’re not out of the woods on this pandemic yet. We need to continue to press ahead.”

Past Covid-19 Infection Gives Vaccine-Like Immunity For Months, Study Finds

Coronavirus immunity: What do we know? | COVID-19 Special - YouTube

TOPLINE

Most people who have recovered from Covid-19 have similar levels of immunity against future infection to those who received a coronavirus vaccine, a study by Public Health England found, offering early hope against fears of a short-lived immunity spurred on by reports of people catching the virus twice, though the researchers warn that those with immunity may still be able to carry and transmit the virus to others. 

KEY FACTS

Naturally acquired immunity from a previous Covid-19 infection provides 83% protection against reinfection when compared with people who have not had the disease before, government researchers found in a study of more than 20,000 healthcare workers.

The study, which has not yet been peer reviewed for rigor by other scientists, shows that this protection lasts for at least five months and is at a level just below that offered by vaccines from Pfizer-BioNTech (95%) and Moderna (94%) and significantly above that of the vaccine developed by the University of Oxford and AstraZeneca (62%), though manufacturers don’t know for how long this immunity lasts.

The figures suggest reinfection is relatively rare — occurring in fewer than 1% of the the 6,614 people who had already tested positive for the disease — though the scientists warned that while “those with antibodies have some protection from becoming ill with Covid-19 themselves,” early evidence suggests that they can carry and transmit the virus to others.

“It is therefore crucial that everyone continues to follow the rules and stays at home, even if they have previously had Covid-19, to prevent spreading the virus to others,” Public Health England wrote.

The study will continue to follow participants for another 12 months to determine “how long any immunity may last, the effectiveness of vaccines and to what extent people with immunity are able to carry and transmit the virus,” as well as investigate the highly-contagious new variant of coronavirus spreading across the U.K.. 

CRUCIAL QUOTE

Professor Lawrence Young, a virologist and Professor of Molecular Oncology at Warwick Medical School in England, said an important takeaway from the study is that we don’t yet know how long antibody protection will last outside of the five month window. He said it is “possible that many people who were infected during the first wave of the pandemic may now be susceptible to re-infection.” Young said it will be interesting to see whether people previously infected with Covid-19 and are subsequently vaccinated have “an even longer-lived protective immune response” and whether or not these findings hold true for the new virus variant currently spreading in the U.K..

WHAT TO WATCH FOR

The information gathered from reinfection cases could prove important as the pandemic progresses, especially when it comes to designing and implementing an effective vaccination program and deciding whether to ease lockdown measures. Whether or not those who are immune to serious illness are capable of transmitting the infection to others will be a crucial deciding factor.

WHAT WE DON’T KNOW

It’s not yet clear for how long the protection provided by vaccines last. This will have to be studied over time, as with this case of natural immunity, and is something manufacturers are already doing. Moderna believes their vaccine offers at least a year’s protection against disease. Whether or not this protection prevents individuals from infecting others will also need to be figured out. 

BIG NUMBER

384,784. That’s how many people have died from Covid-19 in the U.S. since the pandemic began, according to Johns Hopkins university. According to CDC projections, this figure is set to grow 25% in the next three weeks. At the moment, more than 23 million people have contracted the disease in the U.S..

More than 10 percent of the U.S. Congress has tested positive

Which Members of Congress Have Tested Positive for the Coronavirus - The  New York Times

At least 60 sitting members of Congress — more than one in 10 — have tested positive for the coronavirus or are believed to have had Covid-19 at some point since the pandemic began. The list includes 44 Republicans and 16 Democrats.

That’s a higher proportion than the general population. As of Wednesday, a bit fewer than one in 14 Americans are known to have had the virus, according to a New York Times database, though many more cases have probably gone undetected.

Five House members have reported positive tests since the attack on the Capitol last week, when many lawmakers were holed up in a secure location together and some refused to wear masks — a situation that angered several Democrats, including Representative Pramila Jayapal of Washington, one of those who has since tested positive. Congress’s attending physician warned members afterward that it was possible they were exposed while sheltering and recommended that they get tested.

Congress has struggled to stem the spread within its ranks in recent weeks. Most members who have tested positive have done so since the election in November, as coronavirus cases have surged across the country.

Representative Jake LaTurner, Republican of Kansas, said he received word just after the attack on the Capitol last Wednesday that he had tested positive, and did not return to the House floor for a vote early on Thursday.

Representative Gus Bilirakis of Florida and Representative Michelle Steel of California, both Republicans, were absent from the House floor when the mob entered the Capitol because each had received positive test results earlier that morning. Representative Chuck Fleischmann, Republican of Tennessee, said on Sunday that he had tested positive after exposure to Mr. Bilirakis, with whom he shares a residence.

Covid-19 Live Updates: Distracted by D.C. Political Crisis, U.S. Sets Daily Record for Virus Deaths

Moving a Covid-19 victim from a hospital morgue in Baltimore last month.

More than 4,400 people in the country died of the coronavirus on Tuesday, the day before lawmakers were set to charge President Trump with inciting last week’s violence at the Capitol.

RIGHT NOW

More than 10 percent of the U.S. Congress has tested positive.

The fallout from the Capitol siege has overshadowed the surging U.S. virus death toll.

As America slogs through this grimmest of winters, there is no relief in the daily tabulations of coronavirus-related deaths: More than 4,400 were reported across the United States on Tuesday, according to a New York Times database, a number once unimaginable.

Yet even as Covid-19 touches thousands of families, the nation is distracted by the political crisis gripping Washington in the last days of the Trump administration.

Tuesday’s death count, which set another daily record, represented at least 1,597 more people than those killed in the terrorist attacks of Sept. 11, 2001.

The U.S. death toll, already the world’s highest by a wide margin, is now about 20,000 shy of 400,000 — only a month after the country crossed the 300,000 threshold, a figure greater than the number of Americans who died fighting in World War II.

But much of the nation’s attention is focused on the fallout from the Capitol siege, prompted in part by President Trump’s efforts to prevent Congress from certifying Joseph R. Biden Jr.’s victory in the November election.

On Wednesday, the House will vote to formally charge Mr. Trump with inciting violence against the country. House lawmakers have formally notified Vice President Mike Pence that they will impeach the president if Mr. Pence and the cabinet do not remove Mr. Trump from power by invoking the 25th Amendment.

As people in the country wait to see how Mr. Trump’s tenure will end, they have also focused on the stories of the five people who were left dead after last week’s rampage — in particular, the death of Brian D. Sicknick, a Capitol Police officer who was overpowered by the mob and struck on the head with a fire extinguisher.

“Brian is a hero,” his brother Ken Sicknick said. “That is what we would like people to remember.”

Each coronavirus death is no less painful to the families and friends who have lost loved ones. Among the latest victims are a revered basketball coach, a travel writer who loved country winters and an architect who had survived the Holocaust.

The health Secretary Alex M. Azar II tried to highlight the urgency of the crisis on Tuesday as the Trump administration said that it would release all available vaccine doses and instructed states to immediately begin inoculating every American 65 and older.

“This next phase reflects the urgency of the situation we face,” he said. “Every vaccine dose that is sitting in a warehouse rather than going into an arm could mean one more life lost or one more hospital bed occupied.”