(CNN) — For weeks, health experts have warned of another possible covid-19 spike if Americans relax on security measures as the country rushes to vaccinate more people.
Now infections are on the rise again and some state leaders are sounding the alarm about the latest trends.
After weeks of decline and then a plateau, the average number of new COVID-19 cases saw a 7% increase over the previous week, the director of the Centers for Disease Control and Prevention said on Friday ( CDC), Dr. Rochelle Walensky. The average number of new virus-related hospitalizations also saw a slight increase from the previous week, he said.
More than two dozen states are reporting at least a 10% increase in new cases compared to the previous week, according to data from Johns Hopkins University.
And some state officials say that many of the new infections appear to occur among younger groups.
“People over 65 years of age, a large proportion of them, have been vaccinated, they are protected. That’s one of the reasons we haven’t seen a huge increase in hospitalizations, ”Dr. Ashish Jha, dean of the Brown University School of Public Health, told CNN on Sunday. “Much of the spread is happening among younger people … that’s the group that moves, relaxes, gets infected.”
Fueling the increase in cases is a highly contagious and life-threatening variant of the virus. Variant B.1.1.7, first detected in the UK, has now been identified in 51 US jurisdictions, according the CDC, and is expected to become the dominant variant in the country in late March or early April.
But that’s not all that helps drive the increase in cases, experts say.
Governors and local leaders across the country have recently relaxed restrictions aimed at curbing the spread of the virus, while health officials urged them to keep the measures in place for a little longer.
Spring break crowds increased in popular beach destinations, including South Florida, where local leaders said vacationers were more than they could handle. And air travel has broken pandemic records this month, with millions of Americans getting on airplanes.
“We are weeks away from reaching a point where we can start doing these things a little more safely, but I think the states have moved too fast,” Jha said.
So far, about 28.2% of the U.S. population has received at least one dose of the covid-19 vaccine, according to data from the CDC, and 15.5% of Americans are fully vaccinated.
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State leaders sound the alarms
US state leaders have raised concerns about their latest covid-19 data, urging residents to double down on security measures for just a few more weeks until a sufficient number of the population is protected from the virus.
Michigan is in the midst of another covid-19 spike, a senior state health official told CNN on Sunday.
And cases are increasing more in younger people, specifically in the 10-19 age group, said Dr. Joneigh Khaldun, Michigan’s executive medical director.
The state is experiencing community spread, Khaldun said, attributed the increase in cases to a number of factors, including more gatherings and more mobility, economic reopening and specific outbreaks in some prisons and schools.
In Illinois, state officials announced Friday that they were deploying rapid response vaccination teams to multiple counties and expanding vaccine eligibility in response to a “worrying trend of increasing covid hospitalizations and case rates.”
“Recent increases in hospital admissions and test positivity refer to new developments and we don’t want to go down the same path we’ve seen before and experience a resurgence of the pandemic,” said Dr. Ngozi Ezike, Director of the Department of Illinois Public Health, in a release.
“We cannot move forward if our metrics are going backward,” added the director.
Also Friday, Vermont officials reported the state’s highest single-day total cases since the start of the pandemic, with more than 250 new infections reported.
The increase is likely to be driven by more people moving now that warmer weather is here and by variants that are circulating, said Dr. Mark Levine, the state health commissioner.
“Our efforts to vaccinate the citizens of Vermont are a race against what the virus does best – easily pass from one person to another,” Levine said. “Across the country, even up and down the east coast, the number of cases has increased.”
New Hampshire officials reported late last week an increase in the average number of new daily COVID-19 cases and the state’s test positivity rate. And the number of infections among people under the age of 60 is also increasing, especially in teens and people in their 20s, authorities said.
The increase in cases will likely continue for a couple of weeks, Governor Chris Sununu said, adding that the state is likely to see a “spring surge.”
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In Pennsylvania, the governor said last week that the number of new cases and the percentage of positivity across the state increased slightly, calling the increases “worrisome.”
“As more and more Pennsylvanians are vaccinated, we must not forget to follow the mitigation measures that are still in place,” Gov. Tom Wolf said in a release. “As the weather warms up, remember to wear a mask, practice social distancing and wash your hands frequently, as the virus still has a presence in our communities.”
CNN’s Linh Tran and Miguel Márquez contributed to this report.
George is Digismak’s reported cum editor with 13 years of experience in Journalism