O'FALLON, Mo. (AP) — The number of new Missouri coronavirus cases continued to decline on Monday, but state officials cite one cause for concern: Wastewater samples indicate the fast-spreading U.K. variant is “widespread” across the state.

The Missouri Department of Health and Senior Services reported 351 newly confirmed cases of COVID-19 and no new deaths. The state has reported 475,348 confirmed cases and 7,715 deaths since the pandemic began. The number of new daily cases has dropped off sharply over the past several weeks after a surge during the holidays, and hospitalizations have reached the lowest levels since the summer.

The first Missouri case of the U.K. variant was confirmed on Feb. 6 in Marion County in northeast Missouri. It remains the only confirmed case in the state.

But the Missouri Department of Health and Senior Services said wastewater sampling has found the variant across the state. The sampling is part of the Coronavirus Sewershed Surveillance Project created by researchers at the University of Missouri-Columbia in partnership with the state health department and Missouri Department of Natural Resources.

Marc Johnson, a university virologist, told the St. Louis Post-Dispatch that the variant was detected in more than 13 wastewater systems in Missouri. Researchers say the project can provide early detection of an upcoming COVID-19 outbreak or emerging novel viral variants.

“While Missouri has only one confirmed case of a patient with the U.K. variant, we understand this variant is more widespread in the United States and Missouri than detected by clinical and sentinel testing,” Missouri's health director, Dr. Randall Williams, said in a news release.

Williams urged continued precautions such as mask-wearing, social distancing and frequent hand-washing, and urged Missourians to get vaccinated “as vaccines become more available.”

State data on Monday showed that more than 1 million doses of vaccine have now been administered in Missouri, with 11.5% of residents so far receiving at least one dose. Missouri remains in the bottom 10 states for the percentage of residents receiving vaccinations.