There is a growing amount of COVID-19 detected in municipal sewer water across many parts of the U.S., according to the Centers for Disease Control and Prevention.

Bloomberg News reported that from March 1 to March 10, 36% of wastewater sample sites showed rising COVID trends, a sharp uptick from Feb. 1 to Feb. 10, when 15% of wastewater sample sites were rising.

Amy Kirby, head of the CDC's wastewater monitoring program, confirmed to Bloomberg News that there has been a jump in wastewater sample sites that have seen an increase but that wastewater levels are generally very low.

"These bumps may simply reflect minor increases from very low levels to still low levels," Kirby said in an email. "Some communities though may be starting to see an increase in Covid-19 infections, as prevention strategies in many states have changed in recent weeks."

A map from Bloomberg News, which monitored 530 sewage monitoring sites, showed that increases were most concentrated in the Midwest.

It is unclear if the uptick of COVID in wastewater will lead to more infections. The CDC's testing program is limited to areas that collect and report on wastewater surveillance.

The news comes as COVID cases are surging across Europe due to the Omicron variant. According to Johns Hopkins University, the U.S., the Netherlands, Germany, Switzerland and Italy saw an uptick in cases this past week.

The World Health Organization expressed a sense of urgency earlier this month, stating that the pandemic “will not be over anywhere until it's over everywhere," and is closely monitoring the rise of the Omicron subvariant.