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A number of new studies have confirmed the silver lining of the Omicron variant: Even if the number of cases climbs to a record level, the number of severe cases and hospital admissions is not the case.
The data, some scientists say, points to a new and less worrying chapter in the pandemic. . "Now we're in a completely different phase," said Monica Gandhi, an immunologist at the University of California at San Francisco.
“The virus will always be with us, but I hope this variant induces immunity enough that the Omicron variant was discovered in South Africa a little over a month ago, and experts warn that it will be a long time before it Situation is changing, but last week's data suggest that a combination of widespread immunity and numerous mutations resulted in a virus that causes much less serious illness than previous iterations.
A study conducted in South Africa found that patients admitted there during the fourth wave, which was dominated by the virus's omichron, were 73% less likely to develop serious illness than those admitted during the delta-dominated third wave .
"The data is pretty strong now with hospitalizations and 'cases decoupled," said Wendy Burgers, an immunologist at the University of Cape Town.
Initially, much of the concern about Omicron was due to the large number of mutations in the variant, many of which Spike protein, the part of protein found not only easily infects unvaccinated people, but also bypasses antibody responses from previous infections and vaccines.
It worked its way past these first lines of defense. Several factors appear to make the Omicron variant less virulent or less virulent more severe than previous waves of Covid19. The ability of the virus to infect the lungs. Covid infections usually start in the nose and spread to the throat.
A mild infection doesn't go far beyond the upper respiratory tract, but when it does When the virus reaches the lungs, it is usually the hardest, and symptoms occur.
But five separate studies from last week suggested that the variant doesn't infect the lungs as easily as previous variants. In a study preprinted online by a large consortium of Japanese and American scientists, omicron infected hamsters and mice experienced much serious illness with earlier iterations of the virus. took a small number of lung tissue samples from patients during surgery and found that Omicron grew more slowly than other variants in these samples.
Burgers said this change in virulence likely had to do with how the virus's anatomy changed. Pathways into the cells, and now it prefers one of those pathways because of all the changes in the spike protein, "she said.
It seems to prefers to infect the upper respiratory tract rather than the lungs. This, Burgers said, could mean less severe infection but also more transmissible as the virus replicates more often in the upper respiratory tract, from where it can spread more easily Second-line defense of previous vaccines and infections: cells and cells.
T-cells are responsible for attacking a virus once it makes its way into the body’s cells if antibodies fail to prevent infection in the first place. In a recent study by Burgers and colleagues, scientists used white blood cells from Covid patients to show that about 70-80% of the T-cell response is preserved compared with previous strains of the virus. That means that for those who are either vaccinated or had a Covid infection in the past 6 months, it is likely their T-cells can recognize omicron and fight it off relatively quickly.
This latest research will need to be followed up with further study. If it holds up to additional scrutiny, it just might explain why current infections appear to be more mild than in previous waves of the virus.
“When you start to see different kinds of data all pointing in the same direction, you begin to feel more confident that it’s going to hold up,” said Jessica Justman, a Columbia University Medical Center epidemiologist.
However, as cases explode, the absolute number of hospitalizations and deaths with them will continue to rise, even if those numbers increase more slowly.
"If your denominator is huge because lots and lots of people become infected, you still end up with lots of people who go to the hospital and need care," Justman said.
Gandhi of the University of California at San Francisco said that while the number of cases could break records, hope that the combination of highly transmissible omicron and a mild infection could signal the onset of the disease in another study, held in Hong Kong last week showed that vaccinated patients infected with Omicron also evoked strong immune responses to other versions of the virus.
This could explain why the number of cases in South Africa has quickly peaked.
"I hope this variant creates deep immunity in the population." Hopefully the pandemic will end. "
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