Although Chicago is seeing a steady increase in COVID-19 cases amid emerging omicron variants, health officials don’t expect a major increase similar to other US cities in recent weeks.
Chicago Department of Public Health Commissioner Dr. Allison Arwady said Thursday that because the city and the Midwest have seen larger spikes in coronavirus cases with the original omicron variant, BA.1, than other cities, more Chicagoans are protected from the new strains.
“If you had a breakthrough infection, you know that during this January period it was probably Omicron. You have extra protection – we don’t expect 100% protection, but good protection against BA .2,” Arwady said. “That, coupled with being up to date with your vaccines, should help keep Chicago and the entire Midwest in check. BA.2 now represents more than two-thirds of our patients.”
Arwady noted that the BA.2 variant of omicron accounts for about 67% of COVID cases in Chicago and about 72% of cases nationwide. In the northeast, where cities are seeing steep increases, more than 80% of cases – nearly 90% – are the BA.2 strain.
Chicago’s top doctor said earlier this week that she was also not yet concerned about a new hybrid variant of COVID known as XE spreading in the UK, which is making many headlines with concern. as to its transferability.
“Mostly it has been detected in the UK, several hundred cases, but nothing at this stage clearly shows major concern or spread,” Arwady said in a statement. “And so it hasn’t even been labeled at this point, an official variant of interest.”
Arwady noted that while the recombinant variant has already been detected in the United States, no cases were reported in Chicago or Illinois on Monday.
“Any time you see a new variant emerge, the main thing is that it has…it may have a little edge, maybe a bit more contagious, but no, it’s not one of those variants at this point. which worries me specifically,” she said. “It remains a kind of version of omicron.”
The XE variant is a recombinant, meaning it has parts of two different variants rearranged into a new virus, which in this case are BA.1, the original omicron strain, and BA.2, known as name of “stealth omicron”.
It was first detected in mid-January in the UK, where more than 600 cases have since been reported, according to the UK Health Security Agency.
According to the Chicago Department of Public Health, a handful of XE cases have been reported outside of the UK, including in the US.
The recombinant variants themselves aren’t out of the ordinary, according to health officials.
“Recombinant variants are not an unusual occurrence, especially when there are multiple variants in circulation, and several have been identified during the pandemic to date,” Hopkins said. “As with other variant types, most will die fairly quickly.”
In the UK, health officials are monitoring two other recombinants: XD and XF, which consist of genetic material from the Delta and BA.1 strains, as well as the XE variant.
According to the CDC’s website, XE is currently not monitored by US epidemiologists, nor has it been labeled a “variant of interest” or “variant of concern.”
The WHO said it would continue to study the recombinants and provide updates as new evidence becomes available.
XE may be the fastest-spreading strain to date, according to preliminary research, but studies are underway to determine the exact contagiousness of the variant.
The variant’s early growth rates were not significantly different from BA.2, the UK Health Security Agency initially said. However, in a March 25 update, health authorities revealed more recent data showing that XE had a 9.8% higher growth rate than BA.2.
The WHO has published similar information, citing estimates that show XE is 10% more transmissible than BA.2. However, these findings require further confirmation, the agency noted.
The more contagious omicron BA.2 subvariant has become the dominant strain of COVID-19 in the United States, but international health experts are placing greater emphasis on a new hybrid variant that may be even more infectious.
BA.2 was previously identified as the most transmissible variant because it spreads about 75% faster than BA.1, according to health officials.
“Whenever there is a more transmissible virus, it has the chance to become the predominant virus in the world,” said Hannah Barbian, genomic epidemiologist at the Regional Innovative Public Health Lab at Rush University Medical Center.
Experts have said COVID vaccines have been effective against all variants that have surfaced, when it comes to preventing hospitalizations and deaths. However, more studies are needed to see what impact vaccines might have on the XE variant.
So far during the pandemic, new strains and outbreaks have hit Europe and China first, so scientists are keeping a close eye on what happens there.
“The US hasn’t seen evidence of a new outbreak yet, so I think this might be the exception. We’re not sure, but I think we still want to know the virus dynamics in our area. “, said Barbian.