A highly contagious coronavirus variant that is contributing to a surge of cases in Missouri first gained a foothold in rural areas of the state where vaccinations rates are low, a pattern not seen previously.

The delta variant, first detected in India, is becoming the predominant strain detected in wastewater in some parts of the state, particularly in the southwest corner, where COVID-19 hospitalizations are on the rise.

And it is spreading much differently than the alpha variant, which first was detected in the United Kingdom. Jeff Wenzel, who oversees the wastewater surveillance program for the Missouri Department of Health and Senior Services, said the alpha variant spread from cities to rural areas. This variant is doing the opposite.