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Why does Hennepin County have so many more COVID-19 cases, fatalities, than Ramsey?

COVID-19 is hitting Hennepin County far harder than any other county in Minnesota. And its size alone does not explain why.

Roughly two-thirds of the state’s COVID-19 deaths so far have been in Hennepin County, which comprises less than a quarter of the state’s population. Hennepin has twice the population of Ramsey County, but more than eight times as many virus-related deaths.

As with the rest of the state, most of the deaths have been in senior care facilities — about 79% as of last week. Hennepin County has about 3.6 times as many facilities classified as nursing homes and “housing with services” — a broad category that includes assisted living — as Ramsey, which has the second most in the state, according to state data.

State health officials say it is still too early to suss out the explanation for county-level differences in COVID-19 cases.

Kris Ehresmann, infectious disease director at the Minnesota Department of Health, said factors influencing the numbers include the overall population, population density, transit use, the number of elderly and vulnerable people and prevalence of long-term care facilities, among others.

“Until we get to the point of having more uniform, universal testing across the state, we are likely to continue to see differences between locations that we can’t easily explain,” Ehresmann said in a statement.

Susan Palchick, Hennepin County’s public health director, said many variables could be affecting the numbers. The county is preparing to do more contact tracing — tracking down people who came into contact with infected people — following the governor’s call for more testing.

“The number of deaths, particularly in long-term care facilities, is very alarming to us,” Palchick said. “We would love to have a better understanding of what’s driving that, so that we could break that transmission cycle.”

Some of the senior care facilities are known hot spots. At least 50 people have died at two senior facilities in New Hope, while 13 people died at one in Minneapolis.

Dr. Kumi Smith, an infectious disease epidemiologist at the University of Minnesota, said Minnesota is still in the early stage of the pandemic. A lot of the patterns emerging now can be traced back to early events where the virus was spread, she said, and the social networks around those people and places.

“It’s not that we know what those events are, but we know that they can play a big role,” Smith said.

In addition to deaths, Hennepin also comprises about 36% of the state’s confirmed cases of COVID-19.

But those numbers are skewed based on where testing occurs. Ehresmann said more testing is happening in long-term care facilities, and Hennepin County has a lot of them. If one person in a facility tests positive, everyone else in the facility is tested.

“When you start focusing like that you are going to see more disease,” Ehresmann said.

Staff writer Glenn Howatt contributed to this report. 

DATA: See our complete COVID-19 tracking page for Minnesota and the U.S.