The number of new coronavirus cases in Missouri is rising after months of decline, and epidemiologists say a fast-spreading variant of the virus is fueling the increase.
The delta variant was first detected in Missouri in spring and has since spread throughout the state quickly, state health experts said. The variant accounts for about half of the cases involving variants in Missouri, said Dr. George Turabelidze, an epidemiologist at the state Department of Health and Senior Services.
“There’s no doubt the virus is increasing in Missouri,” he said in a recent briefing. “The delta variant is especially concerning. Compared to other viruses that have emerged before, it seems to be more transmissible.”
This week, the state reported 3,628 new cases, an increase of nearly 20% over last week.
The variant likely is driving large outbreaks in the southwest part of the state near Joplin, Springfield and Lebanon, said Marc Johnson, a molecular microbiologist and immunologist at the University of Missouri who tracks the spread of the virus through the statewide sewage surveillance system.
After the variant is found in a city’s wastewater, cases almost always increase in that region, Johnson said.
“Once it moves into a sewer shed, within two or three weeks, you see a noticeable increase in patients and RNA levels in the sewer shed,” he said, noting that the delta variant has spread faster than others he’s tracked in the past year.
The delta variant is not only more contagious than earlier forms of the virus, it appears to make people more sick, said Dr. Hilary Babcock, an infectious disease specialist at BJC HealthCare.
Other, more contagious variants have emerged throughout the pandemic. But even as they spread, they weren’t associated with rising hospitalizations.
“The delta variant does both,” she said. “It’s more easily transmitted between patients, and it increases the severity of diseases in whomever gets it.”
Both the Pfizer and Moderna vaccines have shown to be effective at keeping people from developing severe cases of COVID-19 caused by the variant, but only if they receive both doses of the vaccine, Babock said.
While a single dose of the two-shot vaccines has previously granted protection from other forms of the coronavirus, it’s not enough against delta, she said.
Almost all of the COVID-19 patients at Springfield-based CoxHealth hospitals are unvaccinated, said Steve Edwards, the health system’s CEO.
Even if vaccinated people can contract the disease, having had the shot keeps them out of the hospital and the ICU, he said.
“I would encourage anyone in a community that doesn't have a strong number of variants, especially delta, that the window is still open to protect yourself,” Edwards said.
The number of patients with COVID-19 in Cox hospitals hasn’t reached winter levels, but is increasing, he said. Unlike earlier in the pandemic, there aren’t as many employees at the hospital to take care of sick patients.
The health system last week examined viral genetics of 56 hospitalized COVID patients. Of those, 50 were infected with the delta variant.
Edwards calls the increasing prevalence of the delta variant an “inside-out” version of the original coronavirus spread early in the pandemic, when the disease ravaged the coasts before spreading into the country’s heartland.
The region that includes Kansas, Iowa, Nebraska and Missouri has the highest proportion of the delta variant compared to other regions in the country, according to the Centers for Disease Control and Prevention.
“This isn't a phenomenon that is going to be localized in the Ozarks,” Edwards said. “It just started here. It's going to be across the country. And if your vaccine rates are low, you will have mortality associated with it.”
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