The COVID-19 omicron subvariants BA.4 and BA.5 have rapidly increased their spread in New England over the past several weeks.
US Centers for Disease Control (CDC) data shows that the subvariant first arrived in New England in mid-April, but began to increase rapidly in late May.
The data shows that subvariants accounted for about 6.5% of cases at the end of May, before rising to about 12.4% by the end of the first week of June. The subvariants jumped to about 15.4% of cases the following week, and finally jumped to about 24% at the end of last week.
BA.2.12.1 is still the most prevalent form in the region and nationally, accounting for 68.3% of infections in New England and 56% nationally, but it is possible that we may consider BA.4 and BA.5 to account for Can watch for increasing share. Cases in the next few weeks as in other regions of the country.
In an email Wednesday to Greeley Tribune.com, David Hammer, a professor of global health at Greeley Tribune University (BU), wrote that ba.4 and ba.5 have many of the same mutations that make the original Omron variant so related, but that They also have new mutations that can make them more transmissible.
Hamer said they have a mutation that could make it easier for them to attach to human cells, and another that could make them better able to evade an immune response.
Still, Hammer said, there’s no evidence that these types cause more severe disease, so they’re unlikely to increase hospitalization rates except in people who weren’t vaccinated. or those who have not had a natural infection.
Matthew Fox, an epidemiologist at BU, agreed with Hammer’s assessment of transmission and the lack of evidence that these variants cause more severe disease, and added that they do not appear to have a higher mortality rate than the original Omicron variant. .
“If, however, this variant is able to bypass immunity, we could see more infections than in the last wave, and that could lead to more hospitalizations, because the number of people infected is higher,” he told Greeley Tribune.com. wrote to com. E-mail.
On Wednesday, a study from Harvard University and Beth Israel Deaconess Medical Center that was published in New England Journal of Medicine found that these variants could evade the immune response better than the previous variants.
The study found that the BA.4 and BA.5 variants were three times more resistant to neutralizing antibodies than BA.1 and BA.2, which already had neutralizing antibodies compared to the original COVID-19 virus. are much more resistant to
Because of this, the researchers wrote, BA.4 and BA.5 may also cause substantial increases in populations with high vaccination rates and natural immunity to BA.1 and BA.2, although vaccination still prevents serious disease. Security should be provided.
Hammer said that based on this new information, he believes there could be a substantial increase in infections in New England this summer or early fall.
“This causes some concern,” Fox wrote. “But this is also a small sample, so I think we’ll have to wait and see what happens at the population level.”
Overall, he said, it is too early to tell what impact BA.4 and BA.5 will have as the spread increases in New England.
Fox and Hammer stated that BA.4 and BA.5 have been seen in South Africa and many European countries So far. Hamer said these countries have experienced a gradual increase in cases due to the new forms, but have not seen a large wave of infections.
Fox said infection rates are usually lower in the summer due to higher temperatures and more people being outdoors, but added that there’s really no way to know for sure.
He wrote, “I don’t think there is much cause for concern yet, but … I think we should prepare.” “People should think about what measures they are willing to take when infection rates rise.”
Stay up to date on all the latest news from Greeley Tribune.com