Forget cold and flu season.
Experts are warning that a highly contagious virus many Americans still associate with the winter is now flourishing in the summer months.
And the latest numbers suggest the bug is gaining ground: Infections are growing or likely growing in all 50 states, according to a data from the Centers for Disease Control and Prevention.
That nationwide COVID spread is drawing attention from health officials, particularly after last summer’s surge.
“Our summer peak was much higher in 2025 than it was in the winter,” Dr. Erica Pan, director of the California Department of Public Health and the state public health officer, told the Los Angeles Times.
For now, this summer’s wave isn’t as bad as it was last year. Nationwide wastewater viral activity levels were considered “very low” as of Aug. 14, as were emergency department visits related to the respiratory disease.
Last week, nearly 4% of COVID tests came back positive — compared with more than 9% during the same week a year ago, according to the CDC.
At the time, the US was contending with a surge fueled by the “Stratus” variant, which left Americans battling a persistent, dry cough and other symptoms well into the fall.
That strain and the “cicada” variant — so called for its long hibernation period and noisy return last year — are feeling the uptick.
But just because the current COVID wave is lagging behind last summer doesn’t mean Americans are in the clear. In fact, infections are climbing nationwide, with rates increasing sharply over the last month — particularly in the South and West.
As of Aug. 17, at least 15 states and territories were experiencing active COVID outbreaks, according to the Pandemic Mitigation Collaborative’s data tracker.
“That is troubling, especially if you’re in one of those areas,” Michael Hoerger, an assistant professor at Tulane University School of Medicine who leads the PMC, told Today. “We’re expecting transmission to peak about a week into September.”
The surge comes as Americans face another fall vaccine season, with new guidance on who should get a COVID shot.
Until last year, COVID-19 vaccines were recommended for everyone 6 months and older. But the Trump administration’s CDC has moved away from a universal recommendation, instead adopting a shared clinical decision-making model for people in that age group.
In other words, whether to get the shot is now largely a decision for people to make with their health care providers.
Still, other major medical groups continue to recommend COVID vaccines for the wider population, and NYC Health says they “remain our best protection” against the virus.
“The message is that COVID vaccine and flu vaccine will be available, they’re covered by insurers, they’re recommended by medical societies. People should get them and get them for their kids,” Claire Hannan, executive director of the Association of Immunization Managers, which advocates for immunization programs, told NPR.
An updated COVID-19 vaccine is expected to become available in early fall, with the new shot targeting the XFG variant.
The big question is how many Americans will actually roll up their sleeves. Fewer than 20% of US adults received the most recent COVID shot.
While COVID-19 is no longer the threat it was during the early years of the pandemic, infection can still become serious or even deadly. There’s also the lingering risk of long COVID.
Last year, 20,685 deaths were attributed across the nation to COVID-19 on death certificates, according to the CDC.
Those most vulnerable to severe illness include older adults, people who are immunocompromised, pregnant women and children younger than 5.


