A more contagious version of the COVID-19 omicron variant has been detected in Louisville wastewater.
Researchers at the University of Louisville’s Envirome Institute confirmed the variant’s presence.
“We’ve seen at least two sites in west Louisville that have the BA.2 variant in it,” Louisville Department of Public Health and Wellness medical director Dr. Jeffrey Howard said.
This is not the first time BA.2 has been detected in Louisville.
Ted Smith, director of the Center for Healthy Air Water and Soil at U of L, which helps with wastewater testing, said samples first showed BA.2 five weeks ago.
“It has popped up and disappeared across our community and only recently have we seen a location with a very high proportion,” Smith said.
High proportion means “100% of the sequenced fragments in an area,” according to Smith.
Smith said he’s not concerned about BA.2’s presence.
“Infection levels in people and poop in general are still dropping, which is the most important data point,” Smith said.
While the trend is positive, Howard said the transmissibility of the new subvariant is still concerning.
“Any one person who is infected with the [original] BA.1 subvariant is expected to infect another eight people,” Howard said. “The current data that I’ve seen on the BA.2 subvariant suggests that its r-naught is 12, so it is 50% more infective.”
Similar to the original omicron variant, BA.2 has not been shown to cause more severe symptoms.
Howard said that vaccines appear to be effective against BA.2. He said it’s too early to tell the impact the subvariant will have on hospitalizations and deaths.
Local health officials will be watching. The United States has typically lagged three weeks behind COVID-19 levels in the United Kingdom, which is currently experiencing a BA.2-fueled surge.
That trend might not hold for BA.2.
“Current projections for the U.S. do not suggest that this variant of omicron is gonna as bad as has been in Europe,” Howard said. “We do not expect it to be as bad or us having to transition back to where we were six months ago.”
Successful tactics for previous variants should also work with this one.
“If you’re sick, don’t go work. Don't go to public places and expose people. If you’re immunocompromised or have a certain illness, you should consider wearing masks as you go into public places and finally: get tested,” Howard said.
As of March 19, the Centers for Disease Control and Prevention has reported that BA.2 made up 34.9% of new cases nationally. There has been a slow down in the decline of new COVID-19 cases nationally as well.
