The Omicron variants were all the rage in Covid news in early 2022. But with the new year, a new Omicron variant of Covid has roared onto the scene and is now sweeping the East Coast, where over 75% of known cases are of the newest version.
Delta is done, and the Omicron BQ.1 and BQ.1.1 variants that dominated cases in the fall are waning. The newest mutation, XBB.1.5, accounts for over 40.5% of Covid infections around the country, the Centers for Disease Control and Prevention reports.
That’s a jump of 21% from where the mutation was on the chart just one week ago. It’s being seen in the Northeast portion of the country, where over 80% of the population has been vaccinated and boosted against Covid, but scientists are now casting doubt on the efficacy of those boosters against this variant. XBB.1.5 is highly immune evasive, scientists report, warning that breakthrough cases and reinfections are likely.
Yet it’s not clear that XBB.1.5 causes more severe illness or is a greater threat than previous strains of Covid. During the last week of 2022, some 2,530 Americans died with Covid, compared to 17,048 during the same week in 2021.

The XBB strain has been detected in at least 70 other counties, the World Health Organization said. The variant has not yet made its grand appearance in Alaska, although is now thought to be 18% of cases in the Seattle area.
A study published the scientific journal Cell reports that BQ and XBB variants are “barely susceptible to neutralization” by current vaccines and the newest omicron boosters. The new aggressive variants could “further compromise the efficacy of current COVID-19 vaccines and result in a surge of breakthrough infections as well as re-infections,” the researchers from Columbia University said in the article titled, “Alarming antibody evasion properties of rising SARS-CoV-2 BQ and XBB subvariants.”
One year ago, another study from Columbia University cast doubts on whether the new vaccines, rolled out in 2021, were effective against the now spent Omicron virus, reporting that the variant flavor of the day was “markedly resistant” to vaccines and boosters. In the United States, more than 614 million doses of Covid vaccine have been given and many people have had up to four booster shots.
The most recent updated (bivalent) boosters became available in September for people aged 12 years and older, but these newest scientific studies are throwing shade on the booster’s ability to defend against the new versions of Covid.
