Michigan was making good progress at controlling the spread of the coronavirus pandemic and getting people vaccinated this year when, as a public heath expert put it, the state began to "lift the brakes."
Now, the number of Covid-19 cases is spiking and hospitalization rates have been rising, and on Sunday the state reported that its pandemic testing positivity rate had hit 15.64 percent, the highest single-day percentage since Dec. 2.
Gov. Gretchen Whitmer has acknowledged that the worsening numbers do not look good.
"It's a stark reminder that this virus is still very real," Whitmer, a Democrat, said last week. "It can come roaring back if we drop our guard."
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But as more and more Michigan residents are vaccinated — especially the most vulnerable senior citizens — Whitmer has made no move to reimpose Covid-19 restrictions on residents who are already feeling what public health expert Marianne Udow-Phillips called "pandemic fatigue."
Whitmer, whose team did not immediately respond to a request for comment, needs no reminding that some of the fiercest resistance to statewide lockdowns was in Michigan — she wound up being the target of what authorities said was a right-wing kidnapping plot.
Besides Michigan, Covid-19 case numbers have been rising sharply in states like Hawaii, West Virginia, Pennsylvania, New Jersey and Connecticut, prompting the director of the federal Centers for Disease Control and Prevention, Dr. Rochelle Walensky, to warn of "impending doom" if Americans fail to continue taking safety precautions.
Michigan's hot spot for new cases has been the conservative counties north of Detroit, an area known as the Thumb, a bastion of Trump voters that has been especially resistant to pandemic restrictions and mask mandates.
But now the number of cases is starting to climb statewide, and so are the ages of the newest victims, said Josh Petrie, a research assistant professor of epidemiology at the University of Michigan School of Public Health.
"While new cases have tended younger in this month's increase, cases are now rapidly increasing in all age groups under 60," Petrie said. "Similarly, while some of the largest case counts per population have been in counties in the Thumb region this month, we are seeing increases in cases around the state."
What's behind the trend?
"For the state as a whole, we are seeing increases in travel and nonessential trips outside the home that are approaching pre-pandemic levels," Petrie said. "Certainly, less mask-wearing and social distancing is going to increase risk of transmission."
Udow-Phillips, who heads the Center for Health Research Transformation at the University of Michigan, said: "It's hard to pinpoint any one thing. Yes, we are seeing the more infectious variants. But we're also doing more testing."
What is clear, Udow-Phillips said, is that Covid-19 infections began spreading after the state allowed restaurants to resume indoor dining this year, "and there was an even bigger growth in cases that is directly related to the return of youth sports."
"It's not happening on the field," Udow-Phillips said of the infections. "It's happening in transit and afterward, when people are getting together and eating and not wearing masks. It's happening at parties and where people are socializing. For months, we had been very careful, but when the brakes came off, the cases started to climb again."
That is reflected in the statistics in a new analysis by the MLive media company, the publisher of several Michigan newspapers.
Three weeks ago, the biggest jump in new cases was among people ages 10 to 19 and 20 to 29, the figures showed. Last week, the 20-to-29 group was way ahead of the teenagers, followed by people in the 30-to-39 and 40-to-49 age groups.
"We're definitely seeing the impact of St. Patrick's Day," Emily Toth Martin, a University of Michigan epidemiologist, told MLive.
The increase in new infections has, in the last three weeks, been far smaller in people ages 60 and older, a phenomenon that the Michigan Health and Hospital Association attributed to the success of widespread vaccination among senior citizens.
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In Michigan, 14.64 percent of the population has already been fully vaccinated, according to Becker's Hospital Review. And while that puts Michigan in 30th place nationwide, the state is still doing a better job of getting needles into arms than Pennsylvania, California, Texas, New York or Florida.
About 65 percent of Michigan residents over age 65 have received at least one vaccine dose, while about 45 percent are fully vaccinated, the hospital association and NBC affiliate WDIV of Detroit reported.
Does that reduce the chances of Michigan's being hit by another wave of Covid-19 deaths?
"We can hope that is the case," Petrie said in an email. "However, as noted above this is not just affecting young people and we are starting to see hospitalizations increase rapidly. Increases in deaths often lag cases by several weeks, so we're not out of the woods yet."
Since the start of the pandemic, Michigan has recorded nearly 733,000 infections and more than 17,000 deaths, according to NBC News statistics.