What's behind Michigan's COVID-19 surge? Experts say a number of factors

LANSING – As Michigan heads into a third wave of COVID-19 cases and state health officials aim to slow the spread, there are a number of factors behind the surge.

Michigan is reporting 580.4 new daily cases per million people, among the highest in the nation, and an 18.2% positivity rate. The state reported 3,842 patients hospitalized, a level unseen since the second surge in cases last fall.

Since the pandemic began, 756,564 people in Michigan have tested positive for coronavirus and 16,586 have died, according to the Michigan Department of Health and Human Services.

Federal health officials have pushed Michigan to impose restrictions to stem the virus’ continued growth across the state but Gov. Gretchen Whitmer has resisted taking those steps. The governor has said the surge is driven by rapidly spreading variants of the disease, youth sports and people who no longer follow safety precautions, including wearing masks, avoiding large gatherings and not maintaining social distance.

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Whitmer last week asked schools to pause in-person classes, suspend extracurricular activities, including sports, and for people to avoid indoor dining and large gatherings. Local health officials urged schools to move to online classes as students returned from spring break.

Do the COVID-19 variants matter?

Since the first case of the British COVID-19 variant was detected in Washtenaw County in January, the variants have spread to nearly every county in Michigan.

The British COVID-19 variant is dominant but variants from South African, Brazil and California have cropped up across the state.

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MDHHS labs have identified more than 2,200 variant cases. The state does not sequence every COVID-19 test administered, so the number of variant cases is likely much higher.

Health officials had cautioned that the variants spread more rapidly and can cause more severe illness among those infected.

Who is the new surge affecting?

The new wave of infections is primarily hitting younger people.

Youth sports, in-person classes and social gatherings are driving the case increase among younger people, health officials have said.

Ingham County Health Officer Linda Vail said cases are increasing among the 10-29 age group. Given the immunization rates for those 65 and over, hospitalizations and new infections will skew younger, she said.

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People 10-29 are 30% of the state's total confirmed COVID-19 cases, according to MDHHS.

When will getting vaccinated stop the spread?

Vail said during an April 6 media briefing that the virus will continue to spread until vaccination efforts reach herd immunity, which is about 70% of the population. Until the virus can no longer find a host, an increase in cases is likely.

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Currently, 41% of people in the state have been vaccinated, according MDHHS. Locally, 41% of Ingham County residents, 42% of Eaton County residents and 43% of Clinton County residents have received at least one dose of a COVID-19 vaccine.

Since Dec. 28, 3.3 million first and second doses of a vaccine have been administered in Michigan, according to MDHHS data.

Will new restrictions work?

The last round of restrictions were imposed in November, aimed to slow the spread as the state saw a second wave of new cases. Since then, MDHHS has largely curtailed its restrictions, allowing in-person classes, youth sports and indoor dining with a 50% capacity.

While stay-home orders helped drive down case rates in the first months of the pandemic, the state is "in a different context related to case numbers and hospitalizations," Vail told the State Journal last year. 

Instead of clusters of outbreaks, Vail said, there's now widespread community transmission. 

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Forcing isolation and quarantine is a "different kind of health tool for a different context" and won't work to control community spread, she said.

Health officials say precautions including wearing a mask, avoiding large social gatherings and maintaining social distance are effective to slow the virus' spread.

Contact reporter Craig Lyons at 517-377-1047 or calyons@lsj.com. Follow him on Twitter @craigalyons.