Experts say Covid will continue to hit – and probably will for some time

OYour struggle with Covid-19 – after a rough start, followed by a flurry of infections – seems to have become a regular pattern. It may stay that way for some time.

Although Covid is not as dangerous as it once was, the spread of the coronavirus remains sky high. Meanwhile, thanks to vaccinations and improved treatment, death rates have fallen, and the vast majority of people in the United States have developed some level of protection from the vaccine, previous infection, or some combination of the two.

In some ways, Covid is becoming more and more like other respiratory infections – mild in many people, but sometimes severe in certain high-risk populations.

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Ann Falsey, an infectious disease doctor at the University of Rochester, is treating Covid patients, who are mostly elderly, have compromised immune systems or have heart or lung disease — the same types of people who are hospitalized with the seasonal bug. we will shake.

“In an immunologically normal person, it doesn’t look remotely like Covid,” Falsey said, noting that before vaccines, people overwhelmed hospitals with widespread cases of pneumonia, which are now rare.

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For years, Falsey has studied other respiratory viruses, including the four seasonal coronaviruses that cause a good portion of the common cold. in it a 2013 paper Focusing on two of them, OC43 and 229E, Falsi and colleagues noted that while they usually cause mild or even asymptomatic infections, they can sometimes cause hospitalization and death, especially in the elderly.

In the best-case scenario, it’s probably a long-term exposure to the SARS-CoV-2 virus.

As it turns out, SARS-2 is still killing hundreds of Americans every day.

Since last summer, average daily deaths have rarely fallen below 300. Recently The latest Omicron subvariant is BA.5 above the elevated plateau of cases, another outbreak intensified, with deaths exceeding 400 per day (although the BA.5 wave appears to have peaked). This level is much higher than other respiratory viruses, especially during summer.

“That’s one thing, because we’re going to be exhausted for a long time in this pandemic,” said Jonathan Abraham, an infectious disease physician at Brigham and Women’s Hospital in Boston.

Even more alarming is the fact that many experts do not expect much change anytime soon. And it will be up and down, some guesses The project is 100,000 years old Deaths from the COVID virus, if not more, for the next few years. Seasonally adjusted, that’s 275 deaths per day.

“It’s hard for me to see how anything intrinsic to the virus will really change much unless we try to change the way we treat or manage the virus right now,” said epidemiologist Stephen Kissler. Harvard T. H. Chan School of Public Health. “We’re going to continue to see variants emerge, we’re going to see a spread outside of the winter months, and we’re probably going to see more spread in the winter months in temperate regions — basically when people are packed indoors.”

What that means, Kissler said, is that going forward, Covid could kill two to three bad flu seasons each year.

It won’t necessarily last forever. Many experts see SARS-2 as receding, along with other human coronaviruses, as we continue to build additional layers of immunity. But how long will this process take—three years? five years? 10 years? — remains an open question.

“What are we looking at and how long is this going to last?” Vineet Menaheri, a coronavirus specialist at the University of Texas Medical Branch, said. “Do we have to deal with it like this from now on or is there some kind of relief?” I think the honest answer is, we just don’t know. We have not seen anything like this.”

Apart from death, the current rate of disease is nothing. Mass infections wreak havoc on society and lead to countless cases of prolonged Covid.

Experts point out that there is a place to improve with available toolsEven by vaccinating those who have not finished rolling up their sleeves, who still accounts for a significant proportion of deaths, and by reaching more people with booster shots. U.S. health officials are still trying to expand the availability and use of Covid therapies — both for infected people, like the antiviral Paxlovide that President Biden received. during his last matchthe and A treatment called Evusheldit is given to immunocompromised people who are not infected to prevent the disease.

But the main reason why the country is still recording several hundred Covid deaths per day is because of the high number of infections. Despite regional ebbs and flows, the national caseload has topped 100,000 a day since mid-May and recently topped 130,000. That’s an even bigger tally given that surveillance efforts have backfired and many people have opted out of tests or used them at home.

Hundreds of thousands of cases are reported daily, and a small and declining percentage of those who die can add up to hundreds of deaths per day.

So why, two and a half years into the pandemic, is transmission still ongoing? so high?

First, SARS-2 is exceptional its Omicron variants — has become an incredibly contagious virus compared to other respiratory viruses. Mitigation measures favored last year, such as masks and social distancing, have also been rejected.

At the same time, previous infections do not protect us from re-infection. There is no vaccination either, but they continue to provide strong protection against severe disease. This is the result of both reduced immunity and mutations acquired by different variants.

Recovery from an infection or bed rest does not protect against future infection. Although some reinfections have been documented after several weeks, recent studies Qatar, Portugalthe and Israel all emphasized that, in general, people with a recent infection or shot were less likely to be infected. However, this type of immunity is not very stable and does not reduce the risk of infection to zero. In fact, the virus is still finding many infected people.

All of this contributes to a vicious cycle: The more a virus spreads, the more likely it is that better-spreading variants will emerge, which in turn accelerates transmission.

Even with a virus as contagious as SARS-2, a virus that burns through so many people every year, many experts see us becoming a better place over time.

Most of us, between infections and vaccines, have encountered a virus or its protein three, maybe four, maybe five times. We may need more exposure to really take hold of the virus.

“If you get infected again and again, and it seems to be due to viral evolution on the one hand, and immune suppression on the other hand, the second, third, fourth, these repeated infections probably won’t happen. can be harmful,” said Katya Kolel, an evolutionary biologist at Emory University.

Coell says these repeated exposures, especially the different variants, should trigger a deeper and broader immunity with a stronger arsenal of fighters, such as antibodies and T cells. We can still get infected with SARS-2 dozens of times in our lifetime – just like the coronaviruses that cause the common cold – but most of the time it’s just a whiff. (In rare cases, subsequent infections can make people sicker than previous infections.)

Repeated training of the immune system in the form of booster shots is especially important for the elderly, who have a harder time building an immune defense against a new pathogen and whose defenses decline more quickly than younger people. But over time, people develop immunity when they are young and carry it with them when they are old. People who are 60 now may be as vulnerable to Covid when they turn 75 as people who are 75 now.

Perhaps our deeper immunity extends a more durable defense against infection or makes it less likely that we will spread the virus further. Protection against infection with four seasonal coronaviruses is thought to last for a year or two, but these viruses are not as well studied as SARS-2.

“Is there a limit to immunity that can protect you from infection”? Menaheri said. “If you had asked me two years ago, I would have thought that the vaccine and the infection were enough. Currently, we see that this is not enough,” he said, but added that the reason for this is unclear. Has the virus mutated enough to overcome the immune barriers we have been able to erect so far?

STAT spoke to all the experts for a story that underscores the difficulty of predicting the future with SARS-2. There are factors they cannot predict, such as how the virus will evolve. Will future options appear Omicron drift as we see it in 2022Or will something unexpected, such as Omicron, lower our immunity?

As the master of the virus, we will also win. The government is planning to spread updated Omicron target amplifier shots this fall, especially with the BA.5 subvariant component, which now accounts for 85% of US infections. Even if another Omicron subline dominates at the time, the shots may better match what’s circulating than the original formulation and help boost protection against infection and in turn act as a drag during transmission.

The updated frame combines the BA.5 component with original vaccines targeting the virus protein from early 2020. Teaching the immune system to either option can generally lead to a broader response, says Megan Deming, MD, a virologist and infectious disease physician. University of Maryland.

“Hopefully the breadth of immunity will cover everyone [variant] The next one will come,” Deming said. “And hopefully this fall we’ll be able to turn off the transmission a little bit. We’ll see.”

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