Concern about the highly evolved omicron subvariant BA.2.86 is due to the fact that initial groups of preliminary studies on this virus suggest that it may not be as immune-evasive or dangerous as its numerous mutations suggest. It’s softening.
However, this good news is undermined by the latest COVID-19 data, which show increased hospitalization, emergency room visits and mortality, all of which contribute to the current epidemic series of Omicron subtypes. caused by mutations. US led by EG.5, FL.1.5.1 and XBB.1.16.6. EG.5 is on the rise, but there is no single globally dominant variant.
In the US, hospitalizations increased by about 16% from last week, while deaths increased by about 18%.The rate of positive tests has also steepened, according to Latest data from the Centers for Disease Control and Prevention.
While COVID-19 cases are still low compared to other waves, surveillance and testing systems have fallen to alarming levels, possibly underestimating the true burden of the disease. It means high quality. And the current wave is coming ahead of fall boosters, raising concerns for those most vulnerable to the virus.
“one of [the World Health Organization’s] “Our biggest concern is the low level of people at risk who have recently received the COVID-19 vaccine,” WHO Director-General Tedros Adhanom Ghebreyesus said at a news conference on Wednesday. “Our message is to get a booster. It means we shouldn’t wait for .” If you recommend “
As reported by NBC News, U.S. Food and Drug Administration could approve fall boosters as early as this FridayHowever, the timeline could slide to early next week. The CDC is expected to approve the shots shortly thereafter.
Data to date suggest that these fall boosters designed to target XBB.1.5 are effective against the current major variants, namely EG.5 and FL.1.5.1 doing.in Wednesday press release, According to Moderna, the booster is also effective against BA.2.86. Preliminary clinical trial data showed that the vaccine increased his neutralizing antibodies to BA.2.86 by 8.7-fold.
Experts are still unsure how BA.2.86 will unfold, take over, disappear, or evolve into a more nightmarish variant. The staggering number of mutations now in existence and the seemingly sudden global spread raised alarm last month. But even weeks later, mutated ohmic submutants are still a rare find. At the time of publication, the following researchers BA.2.86 Only 12 countries reported only 64 genome sequences Among the thousands of SARS-CoV-2 sequences submitted every week from around the world. Meanwhile, about 30 percent of recently submitted sequences are EG.5, WHO’s coronavirus disease technical director Maria van Kerkhove said Wednesday.
BA.2.86 “isn’t going to outperform the variants currently in focus or other variants in circulation, that’s what we’re looking at,” Van Kerkhove said.
latest data
Three new studies (all non-peer-reviewed preprints) published in the last few days may help explain why variants have largely remained on the sidelines. Taken together, these studies suggest that BA.2.86 may not be as capable of infecting human cells as other submutants currently circulating, and that mutations may be associated with high levels of infection accumulated by past infections and vaccination. This suggests that levels of immunity are not sufficient to overcome. Preliminary data is encouraging, but researchers warn that BA.2.86 could continue to evolve, and could have dodged bullets as COVID-19 surveillance systems were significantly degraded. are doing.
As one of the pre-print studies, Chinese researchers found that BA.2.86 was less efficient at infecting laboratory cells compared to other circulating ohmic submutants, namely XBB.1.5 and EG.5. did. “In summary, BA.2.86 appears to have acquired greater immune evasion in exchange for its infectivity during long-term host virus evolution,” the researchers concluded. However, they cautioned that “very close attention should be paid to monitoring additional mutations that may increase the infectivity of BA.2.86.”
Preprint study by Swedish researchersOn the other hand, we investigated the extent to which sera from blood donors could neutralize BA.2.86 compared to XBB.1.5 and BA.2 (an Omicron subvariant derived from BA.2.86). There was a reduction in neutralization levels against BA.2.86 compared to other variants, but not as severe as initially feared. In one analysis of recent serum samples taken while the XBB mutant was in circulation, neutralizing antibody levels against BA.2.86 were modest compared to those seen against his XBB.1.5. , but still quite strong. The modest reduction to BA.2.86 compares to the extreme immune evasion seen when the original Omicron subvariant arose in the delta subvariant background and led to a massive wave of infection in early 2022. It looks inferior.
Third preprint studyA study led by Boston researchers reached similar conclusions to the Swedish study. The US-based group examined neutralizing antibody responses in 66 people (44 who received bivalent boosters last year and 22 who did not receive boosters). Overall, neutralizing antibody levels to BA.2.86 were significantly lower than neutralizing antibody levels to BA.2.86. BA.2, but has been seen for a number of other circulating ohmic submutants, namely XBB.1.5, XBB.1.16, EG.5, EG.5.1, and FL.1.5.1. was “equivalent to or slightly higher” than
in Post to XBen Murrell, senior author of the Swedish study and Karolinska Institutet researcher, concluded from the data:[O]Your antibodies do not appear to be completely ineffective against [BA.2.86]But he offered a word of caution for the future: “However, the fact that another Omicron-like emergence event, with its long-unobserved divergence, occurred [of evolution] And the ensuing epidemic should caution us against abandoning our genome surveillance infrastructure. “
