KNOXVILLE, Tenn. (WATE) — Just over a year after the World Health Organization said that the world was facing the Omicron variant, a new subvariant trend is causing concern according to the World Health Organization.

The BQ. 1 and BQ. 1.1 Omicron variant began showing up in Centers for Disease Control variant proportions for the United States in early September, and now account for am estimated 62.8 percent of cases in the United States between both variants. Meanwhile, the BA. 5 variant, which appeared to be the most common Omicron variant over the summer, has had a downward trending percentage, only accounting for 13 percent of the CDC’s most recent variant proportions for the U.S.

According to minutes from the WHO’s press conference on global health issues from October 19, the cause for concern comes as the BQ. 1 and BQ. 1.1 variants appear to be subvariants of the BA. 5 variant.

“This is of concern for us because we need to ensure that the vaccines that are in use worldwide remain effective at preventing severe disease and death. So, the more this virus circulates, the more opportunities it has to change.” said Dr. Maria Van Kerkhove, an Epidemiologist who serves as the WHO’s COVID-19 technical lead, has been with WHO and holds a a PhD in Infectious Disease Epidemiology according to her Linkedin profile.

In this press conference, Kerkhove also mentioned that there are more than 300 sublineages of Omicron worldwide that the WHO and its partners are tracking and that none of the subvariants are dominant at this point. In regards to BQ. 1.1, it appears that the subvariant’s severity has changed according to Kerkhove, although she also added that it is very early and the WHO has limited data to assess the severity.

One key note that was also mentioned in the press conference pertains to the XBB subvariant, which is also a Omicron subvariant and makes up an estimated 5.5% of cases on the CDC’s latest variant proportion tracker. Kerkhove said that in a a study based on a psuedovirus that analyzed antibody escape, the XBB pseudovirus showed significant immune evasion.

Across East Tennessee, COVID-19 community levels are low in most places according to the CDC’s map. On the eastern half of the state, only Washington, Unicoi, Carter, Pickett, Overton, Putnam, White, Jackson and Clay have a medium COVID-19 community level on the latest CDC tracker from between November 23 and 29.