Cases are on the rise in most states, and in Washington, Mississippi, Georgia, Maine, Hawaii, South Dakota, Nevada and Montana it is up 50% from the previous week. In New York, more than a quarter of the state’s population lives in Cowid-19, a district with a “high” level of community, where the U.S. Centers for Disease Control and Prevention recommends wearing a mask indoors.
The average daily intake has increased by 10% since last week, according to data collected by the U.S. Department of Health and Human Services.
This time the culprit appears in the spin of BA.2.12.1, a sub-variant of Omicron’s BA.2.2, which was first identified by New York State health officials in April.
According to new estimates from the CDC, BA.2.12.1, which grows 25% faster than its main virus, BA.2, accounts for almost 37% of all Covid-19 cases in the United States.
BA.2 accounted for approximately 62% of all Covid-19 cases last week, down from 70% in the previous week.
The U.S. and South Africa are struggling with new options faster
BA.2.12.1 is not the only Omicron branch that scientists are seeing.
After a few weeks of decline, its Covid-19 incidence in South Africa has risen sharply in the last two weeks. The researchers found the prevalence of two relatively new subvariants, BA.4 and BA.5, in the country, which led to test positive and predominant hospitalizations. According to the South African National Institute of Infectious Diseases, they accounted for almost 60% of all new Covid-19 cases by the end of April.
These new Omicron subvariants are spreading around the world. The BA.4 sequence was reported in 15 countries and 10 U.S. states, and the BA.5 was obtained in 13 countries and five U.S. states, according to the Outbreak.info website, supported by a coalition of academic research centers. Supported by funding from national health institutions.
Like BA.2.12.1, BA.4 and BA.5 have a growth advantage over BA.2.
Omicron subvalants avoid immunity
Researchers in South Africa tested the ability of antibodies in the blood to neutralize BA.4 and BA.5 viruses in the laboratory. In unvaccinated but recently cured BA.1 infections, they found a more than seven-fold decrease in the ability of antibodies to neutralize BA.4 and BA.5 viruses. In people who were vaccinated but recently became infected with BA.1, the drops were fewer, about three times less.
For comparison, the World Health Organization uses an eight-fold reduction in neutralization as a threshold for loss of protection that requires the renewal of seasonal influenza vaccines.
The results of the study led researchers to write that “BA.4 and BA.5 could lead to a new wave of infection,” which made Covid-19 vaccinations and butchery shots crucial to stop the next wave.
“Our conclusion is, first of all, that Omicron itself is not a big vaccine, is it?” Alex Seagal, a virologist at the African Institutes of Health, who led the study, said. “Just because you’re infected doesn’t mean you can protect yourself from further events.”
Dr. Eric Topol, cardiologist, founder and director of the Scripps Research Translation Institute, praised the study, noting that it was the first laboratory to characterize the first Omicron variant: the pandemic.
According to him, in general, this result is not good news. People who recover from Covid-19 infection in December or January may also be re-infected with these new subvariants.
“Immune avoidance or immunodeficiency has been observed in unvaccinated people,” Topol said, noting that only about 1 in 3 people in South Africa has been vaccinated against Covid-19.
For those vaccinated, “those people are not bad either, but they should face BA.4 and BA.5 with a less severe neutralizing antibody reaction,” he said. “Mutations in BA.4 and BA.5 are complicating our immune response.”
Several dozen sequences of these viruses have been reported in the United States and Canada. According to scientists, it is too early to know whether BA.4 or BA.5 can fly in the United States.
It’s not surprising if they do, said Andy Pekos, a virologist and professor of molecular microbiology and immunology at Johns Hopkins University.
“We’ve seen it over and over again. Because the option is dominant in another country, it will end up here in the United States. and spreading around the world, ”Pekosh said.
At the same time, said Topol, we have our own sublink: BA.2.12.1.
“It could be similar to the BA.4 and BA.5 problems,” Topol said. “We don’t know yet because there is no such study from Seagal Laboratory.”
BA.4 and BA.5 viruses and BA.2.12.1 have mutations in 452 locations in their genomes. This area encodes part of the domain that binds the virus receptor – the part of the virus that is installed on the door outside our cells. The Delta variant and some others have received mutations here. Researchers believe that the changes are closely linked to our virus cells and help us to hide from immune defenders called antibodies.
“It could probably hold better even between our cells,” Seagal said.
Versions BA.4 and BA.5 also have changes to the 486 location, which is a bit of a hassle because the previous viruses that changed here did not work well. They screamed.
“Suddenly this guy is in control of it. So we don’t know what it’s going to do,” Seagal said. “I suspect it’s a difficult escape,” he said, adding that the virus helps hide it from our immune system.
Researchers are trying to better understand BA.2.12.1 found in 22 countries, but most of the lists come from the United States.
Pekosz said he is growing copies of BA.2.12.1 in his lab and recently sent samples of the virus to other research groups for study. According to him, scientists have begun to talk about the experiments they want to do to answer two main questions: how quickly is it copied and how well does it get rid of our immunity?
Prior to the SARS-CoV-2 virus, researchers thought that coronaviruses had not changed much. Pekosh looked back and said we didn’t know what we didn’t know.
As the virus continues to find hosts to infect, it continues to develop.
“It showed that the virus mutated gradually, but when it starts getting good mutations, they keep coming and going,” he said.