MILWAUKEE — Over the past year, the scientific world has seen a steady flow of research updating what we know about the novel coronavirus, SARS-CoV-2, and how it affects humans.
Because the virus is so new, researchers are still grappling with many questions about its function. And because of the nature of the scientific process, no single study can completely answer those questions. Instead, new research is constantly challenging our understanding of the pandemic.
Here, we explore some recent studies that have shed new light on the virus.
Scientists are identifying more “homegrown” virus variants in the U.S.
As the coronavirus has kept spreading across the world, it’s been giving itself a bit of a makeover.
Researchers in other countries previously discovered variants of the virus that had racked up high numbers of mutations. And now, scientists in the U.S. are finding more viral variants popping up with similar changes.
Earlier this month, researchers at LSU Health Science Center Shreveport identified a new batch of seven variants in a preprint study.
The variants — which the scientists named after birds, including “Pelican,” “Robin” and “Mockingbird” -- stretch across the U.S., and share one key mutation: A change in the spike protein at a location known as Q677.
Though researchers aren’t exactly sure how the Q677 mutation affects the virus, it is in a troubling spot, since the spike protein is used to infect cells and is also the target for vaccines and treatments.
Other notable variants across the world — including the ones first discovered in the U.K., South Africa, and Brazil — also have mutations that affect the spike protein. So, even though viruses mutate all the time as they make copies of themselves, the fact that we are seeing similar changes crop up could mean that the virus is adapting to its human hosts.
“I think there’s a clear signature of an evolutionary benefit,” senior author Dr. Jeremy Kamil told The New York Times.
This “flock” of U.S. variants has been gaining ground in the U.S., the researchers found, with “Robin” detected in 30 different states and “Pelican” making up almost 30% of cases in Louisiana.
This week, a pair of preprint studies also raised alarms about a variant that appears to have emerged in New York City, known as B.1.526. A research team at Columbia University Medical Center told CNN that they’d seen cases of the variant rise “alarmingly” in recent weeks, and were concerned about a mutation that could potentially help evade antibody treatments.
And a variant that has become prevalent in California may be more transmissible and more lethal, according to UCSF researchers.
Scientists found that, compared to other versions of the virus, hospitalized patients infected with this variant were more likely to be placed in the ICU or die from COVID-19. They also carried more virus in their noses — a sign that the variant may spread more easily.
“The devil is already here,” Dr. Charles Chiu, who led one of the studies, told the Los Angeles Times. “I wish it were different. But the science is the science.”
Of course, there are many complicating factors in figuring out whether a variant is actually more dangerous, and scientists say more study is needed to hash out the specifics of these new variants. The U.S. still lags behind other countries in genetic sequencing of coronavirus samples.
The upside is that we already have many of the tools to fight off the coronavirus. Staying home, wearing masks, and social distancing — as well as getting vaccines in arms ASAP — are still key to staying safe from these new variants and preventing new mutated viruses from emerging.
“You don't want people to become complacent,” infectious disease expert Dr. Anthony Fauci told Axios. “We still have a long way to go.”
Good news as vaccines are put to the real-world test
Clinical trials are a key step in making sure vaccines are safe and effective, and several COVID-19 shots passed with flying colors. But a key question remained: How would vaccines perform out in the “real world” as they made their way into arms across the globe?
Luckily, recent research has underlined that the vaccines are living up to expectations beyond their trial runs.
In Israel — where the world’s fastest vaccination campaign is underway — the Pfizer shots have already been highly effective at stopping sickness, according to a pair of recent studies.
One study, the largest of its kind so far, looked at data for 600,000 vaccinated people and compared them to 600,000 who hadn’t gotten their shots. Researchers found that among the vaccinated group, symptomatic infections had dropped by 94%, matching the high efficacy rate from Pfizer’s clinical trials.
Another study from Sheba Medical Center found that even after one shot of the two-dose vaccine series, health workers were 85% less likely to be infected.
“The vaccine fulfilled the promise that was there,” senior author Ran Balicer told STAT News. “And it was somewhat of a surprise to see that in a real-world setting, a vaccine was able to perform as well as it did in the very controlled setting of a clinical trial.”
Notably, the shots also appeared to reduce total transmission in Israel, including asymptomatic cases. A big question hanging over the rollout has been whether vaccinated people can still catch the coronavirus and pass it on, even if they don’t feel sick.
Other countries are seeing the benefits of vaccines too. In the U.K., the Pfizer and AstraZeneca vaccines slashed the rates of COVID-19 hospitalizations, researchers reported. The shots appear to be saving people from severe symptoms, even in a place where one of the worrisome coronavirus variants has become dominant.
And in the U.S., a New York Times analysis found that nursing home deaths have dropped off significantly since the vaccine rollout began. Even as the overall number of deaths spiked in January, nursing homes, which were some of the first places to get the vaccine, saw their numbers drop off by more than 65%.
“I’m almost at a loss for words at how amazing it is and how exciting,” Dr. David Gifford, the chief medical officer for the American Health Care Association, told The Times.
Rogue antibodies may betray the immune system in severe COVID-19 cases
Normally, antibodies are our friends. They’re some of the tiny warriors sent out by our immune system to fight off invaders — like, for example, an unfamiliar coronavirus.
But a growing number of studies have found that in some cases of COVID-19, our antibodies may turn against us. Rogue molecules known as “autoantibodies” can attack the body’s own tissues, potentially causing symptoms to hit harder or stick around longer.
Around 10 to 15% of people produce some autoantibodies, The New York Times reports, and they don’t always lead to illness. But these types of self-sabotaging antibodies can play a role in autoimmune diseases like lupus or rheumatoid arthritis, when they cause pain and swelling by attacking different tissues in the body.
Several studies have now found heightened autoantibody levels in patients with severe COVID-19 cases.
In December, a preprint study from Yale University researchers found that hospitalized COVID-19 patients had high levels of autoantibodies compared to uninfected people. These rogue antibodies were poised to attack key pieces of the immune system, and also proteins in the blood vessels, heart, and brain — areas where COVID-19 symptoms have shown up in some patients.
Other studies of COVID-19 patients have found autoantibodies that attack various key targets: Patients’ own DNA, proteins that help control blood clotting, anda key immune molecule known as interferon.
The role of autoantibodies could help explain why severe symptoms show up later in a COVID-19 infection, even after the levels of virus have passed their peak, as Nature reports.
“Clinicians are thinking, ‘Oh, this virus is so deadly. We’ve got to get rid of the virus,’” NYU emergency medicine doctor David Lee told Nature. “But then when you talk to the pathologists, they’re like, ‘Yeah, so we’re seeing all this damage, but not seeing much virus.’”
The cause-and-effect relationship is still unclear. In some cases, it seems that autoantibodies emerged as a result of the illness, as The New York Times reports, and, in some cases, stuck around for months — a possible link to the “long COVID” phenomenon.
But it could also be the case that some people already have autoantibodies, which act up and cause severe symptoms when they do catch a COVID-19 infection, as The Conversation explains.
Either way, understanding this link — of how the virus might turn our immune systems against us — may hold clues to better treatment and more answers for COVID-19 patients.
With pandemic protections in place, flu barely showed up this year
As the flu season started getting underway in the fall, many experts were worried. With the influenza and the novel coronavirus both circulating, the prospect of a “twindemic” loomed large.
But the reality was much different: This year, the flu almost disappeared in the U.S., reaching its lowest level in decades.
Out of 25 years with the current surveillance system, “this is the lowest flu season we’ve had on record,” Lynnette Brammer of the Centers for Disease Control and Prevention told the Associated Press.
Since September, labs across the country have reported more than 980,000 flu tests to the CDC. Only around 1,700 of those have come back positive — a positivity rate of less than 0.2%. And only 183 hospitalizations have been reported across the country this year.
In comparison, by the end of last February, the CDC was reporting more than 200,000 positive flu tests and nearly 17,000 flu-related hospitalizations. So, both total cases and severe illnesses from flu were around 100 times as high last year.
The preventive measures we’ve taken to flatten the COVID-19 curve probably played a role, experts say. With less travel and less in-person contact, plus more mask wearing and more hand washing, the flu had less room to take hold.
And since the flu is less contagious than the coronavirus — as well as being less dangerous — the measures may have worked better on driving flu season into the ground, even while COVID-19 continued to spread.
“Flu just tends to be a lot less transmissible, which means it’s easier to suppress it,” Shweta Bansal, a disease ecologist at Georgetown University, told The Atlantic. “That’s partly why we’re getting away with an imperfect response right now.”
This doesn’t mean the flu is gone for good: Experts think it will still make a comeback this upcoming year. And the low levels from this season may actually be a challenge for the scientists trying to develop the next round of flu shots, who rely on annual surveillance to figure out which strains to target.
But now, at least, Americans have more practice with the public health measures that can help fight off the flu — so make sure to hang onto those masks.
Other news to note:
Americans’ life expectancy dropped by a full year in the first half of 2020, largely because of the pandemic, according to a CDC analysis.
The U.K. approved the first “human challenge trial” for COVID-19 — which will infect volunteers with the coronavirus on purpose, in order to study the virus and test different vaccines.
For people who have already recovered from COVID-19, a single vaccine dose may be enough to provide strong protection, two studies suggested.
Many scientists believe the coronavirus will never fully disappear, according to a Nature survey. Instead, it could become endemic and keep circulating at lower levels.