As the BA.5 variant spreads, the risk of covid reinfection increases

America has decided the pandemic is over. The coronavirus has other ideas.

The latest offshoot of omicron, BA.5, has quickly become dominant in the United States and, thanks to its elusiveness when encountering the human immune system, is driving a wave of cases across the country.

The size of this wave is unclear as most people are testing from home or not testing at all. The Centers for Disease Control and Prevention last week reported just over 100,000 new cases a day on average. But infectious disease experts know that grossly underestimates the true number, which may be as high as one million, said Eric Topol, a professor at Scripps Research who closely follows pandemic trends.

Antibodies from vaccines and previous covid infections provide limited protection against BA.5, leading Topol to call it “the worst version of the virus we’ve seen”.

Other experts point out that although it has been hit by several rounds of increasingly contagious omicron subvariants, the country has yet to experience a dramatic spike in hospitalizations. About 38,000 people were hospitalized nationwide with covid on Friday, according to data compiled by The Washington Post. This figure has been constantly increasing since the beginning of March, but remains well below the record 162,000 patients hospitalized with covid in mid-January. The average daily death toll on Friday stood at 329 and has not changed significantly over the past two months.

Tracking US covid-19 cases, deaths, and other metrics by state

There’s a broad consensus among infectious disease experts that it’s a dangerous virus that causes disease of unpredictable severity – and they say the country isn’t doing enough to limit transmission.

Restrictions and mandates are long gone. Air travel is almost back to pre-pandemic levels. Political leaders let’s not talk about the virus – it’s practically a non-issue on the campaign trail. Most people are done with masking, social distancing and the pandemic in general. They try their luck with the virus.

“It’s the Wild West out there,” said Ziyad Al-Aly, an epidemiologist at Washington University in St. Louis. “There are no public health measures. We are in a very particular place, where the risk is acute and it is there, but we let our guard down and we chose, deliberately, to expose ourselves and to surrender. more vulnerable.

Angela Rasmussen, a virologist at the University of Saskatchewan, would like to see more money for vaccine testing and development, as well as stronger messaging from the Biden administration and senior health officials. She was appalled recently on a trip to Southern California, where she saw few people wearing masks at the airport. “That’s what happens when you don’t have politicians and leaders who take a strong stand on this,” she said.

The CDC said it urged people to monitor community transmission, “stay informed about vaccines, and take appropriate precautions to protect themselves and others.”

Covid deaths no longer overwhelmingly among the unvaccinated as numbers of older people rise

Nearly a third of the US population lives in counties classified as having “high” levels of transmission by the CDC. Cases are increasing especially in the South and West.

Many people now view the pandemic as part of the fabric of modern life rather than an urgent health emergency. Part of this is simply a general recalibration of risk. It’s not spring 2020 anymore. Few people remain immunologically naive to the virus. They can still be infected, but the immune system — primed by vaccines or previous bouts with the virus — usually has deeper layers of defense that prevent serious illness.

But the death rate from covid-19 is still far higher than the death rate from influenza or other contagious diseases. Officials have warned of a possible fall or winter surge — possibly up to 100 million infections in the United States — that could flood hospitals with covid patients. Beyond the direct suffering from such a massive outbreak, there could be economic disruption as tens of millions of people become too sick to work.

“It’s like everyone has given up,” said Mercedes Carnethon, an epidemiologist at Northwestern University Feinberg School of Medicine.

Carnethon said she wasn’t as careful as she used to be. She wears a high-quality mask on airplanes, but does not wear a mask in the gym. She is worried about contracting covid again – she caught it during the omicron wave last winter. But she doesn’t think a “zero covid” strategy is plausible.

“I think there’s a very limited amount that I can do individually, unless I stop my life,” Carnethon said. ” It’s risky. I will catch covid at an inopportune time. I can hope it’s softer than the first time I caught it.

Many experts concerned about the ongoing transmission have also pushed back on online fear campaigns and doomsday warnings about the virus; people don’t routinely get infected every two or three weeks, Rasmussen said.

Population-level immunity is one of the reasons the virus remains in mutational overdrive. The risk of reinfection has increased because the newly emerging subvariants are better able to evade the immune system’s frontline defense, and there are virtually no community-level efforts to limit transmission.

They have become covid. Then they got it again.

Al-Aly, who is also head of research and development at Veterans Affairs St. Louis Health Care System, scoured the VA’s extensive database to see what happened to the nearly 39,000 patients infected with the coronavirus for the second or third time. What he found is sobering. In a paper published online last month, but not yet peer-reviewed or published in a journal, Al-Aly and his co-authors reported that people with multiple infections had a higher cumulative risk of severe illness or of deceased.

It is not that later illnesses are worse or even as severe as earlier cases. But any coronavirus infection carries risks, and the risk of a very bad outcome – a heart attack, for example – builds cumulatively, like a plaque, as infections multiply.

“Reinfection adds risk,” he said. “You roll the dice again. You are playing Russian roulette.

Vaccination remains an important, if still underused, weapon against the virus, although it is not as effective in stopping new infections.

Omicron blew through the widely vaccinated population last winter with astonishing ease, and since then the the sub-variants have arrived in quick succession, starting with BA.2 and BA.2.12.1 in the spring, and now BA.5 and its nearly identical parent BA.4.

The vaccines are based on the original strain of the virus that emerged in Wuhan, China in late 2019. The Food and Drug Administration has asked vaccine makers to come up with new formulations targeting BA.5 and BA.4. These boosters could be ready this fall.

But there is no guarantee that these latter sub-variants will still be dominant four or five months from now. Not only is the virus evolving, but it is doing so at a remarkable speed. The virus can continually overtake vaccines.

“I fear that by the time we have a vaccine for BA.5, we will have a BA.6 or a BA.7. This virus continues to thwart us,” Al-Aly said.

The lucky few who never caught the coronavirus could tell us more about it

“We’re in a very difficult position when it comes to choosing the vaccine for the fall because we’re dealing with a notoriously moving target,” Anthony S. Fauci, President Biden’s top pandemic adviser, told The Post. in June, a few days before he too announced he was sick with the virus.

There is already another omicron sub-variant that has caught the attention of virologists: BA.2.75. First seen last month in India, it has been identified in a handful of other countries, including the United States. But it’s too early to tell if it will overtake BA.5 as the dominant variant.

There is no evidence that the new forms of the virus cause different symptoms or disease severity. Omicron and its many offshoots – including BA.5 – typically replicate higher in the airways than earlier forms of the virus. This is one theory as to why omicron seems less likely to cause serious illness.

It’s also unclear whether these new variants will change a person’s risk of getting the long-lasting symptoms commonly known as “long covid.” According to Harlan Krumholz, professor of medicine at Yale University, the percentage of people with severely debilitating symptoms is probably between 1 and 5%, which represents millions of people in this country.

Her colleague, Akiko Iwasaki, a professor of immunology and an expert on long covid, said in an email that she believed the world was no longer sufficiently vigilant about the disease. She is often the only person masking up in a crowd, she said.

“I understand the pandemic fatigue, but the virus is not done with us,” she said. “I fear that current human behavior will lead to more people becoming infected and contracting long term covid. I am afraid that this situation will lead to a large number of people with disabilities and chronic health problems in the future.

The early nature of the virus has made infectious disease experts reluctant to predict the next phase of the pandemic. Topol warns that a new batch of variants could come out of nowhere, similar to how omicron unexpectedly appeared last November with an astonishing collection of mutations already bundled together. The precise origin of Omicron is unknown, but a prevailing theory is that it evolved in an immunocompromised patient with a persistent infection.

“Inevitably, we might see a new family of Greek letters like omicron,” Topol said. “There is still room for this virus to evolve. It has been evolving in an accelerated fashion for months now. So we have to count on it. »

Comments are closed.