Just when many people were ready to declare victory over influenza, the virus changed the script…again! In late January, headlines suggested that flu season had peaked and was on the way out. Case counts appeared to be drifting downward, and there was hope that the worst was behind us. But early February delivered a familiar surprise: flu activity stalled instead of fading, and then edged back up. The Centers for Disease Control and Prevention has now acknowledged what many clinicians were already seeing on the ground: influenza isn’t done. Instead it is lingering, just as it did in the Southern Hemisphere six months ago.
This isn’t a fluke. It’s part of a pattern we’ve seen before.
A Flu Season That Refuses to Wrap Up
During the most recent reporting week, about 4.6% of visits to healthcare providers were for influenza-like illness, slightly higher than the week before. That may sound like a modest change, but at this stage of winter, flu usually retreats—not regroups.
Remember, I have warned you on several occasions that the Centers for Disease Control data are always behind. In Flu Watch #5 we noted that “CDC’s surveillance metrics are 2 to 4 weeks old.” That means that what you read about in the headlines will also be delayed.
Over the past two years, influenza has followed a similar trajectory: an early surge, a mid-season pause, and then a second act that stretches well beyond expectations. This drawn-out pattern mirrors what unfolded recently in Australia, New Zealand and South Africa, where flu season ran long instead of burning out.
On a personal note, we ran into a colleague who went to New Orleans for Mardi Gras. She came home with…you guessed it…the flu!
What we’re seeing now is best described as the long tail of flu season—a slow fade rather than a clean finish.
Why Influenza Isn’t Done
One reason influenza remains stubbornly present is that the cast of viral characters keeps changing.
- Influenza A, which dominated earlier in the season, is beginning to decline.
- Influenza B, however, is gaining momentum—and historically, it tends to show up later and linger longer.
Among influenza A infections, a particular strain—H3N2 subclade K—played an outsized role earlier this winter, especially in young children. Pediatric hospitals reported high fevers, dehydration, and in some cases febrile seizures. For adults and seniors, the CDC has classified this season as moderate. For children, it has been severe.
Now, with influenza B ramping up, the season may stretch well into late winter or even early spring.
Why Early “Peaks” Can Be Misleading
Public health surveillance always involves a lag. Data must be collected, verified, and analyzed before it’s released. By the time numbers appear in weekly reports, they often reflect what was happening one to two weeks earlier.
That delay can make influenza trends look rosier than they really are, especially during a transition period when one strain is declining and another is quietly rising. It is entirely possible that as you read this influenza activity could be coming down…or going up. We think it would be prudent to assume, though, that influenza isn’t done with us quite yet.
Monitoring Poop and Pee:
Wastewater monitoring, which tracks viruses circulating in communities before people even show up in clinics, continues to show high levels of influenza A and B in many parts of the country. Influenza B, in particular, has been trending upward for several weeks.
Flu Isn’t the Only Thing Circulating
Influenza is sharing the stage with a crowded lineup of other infectious diseases:
- COVID-19
- Respiratory syncytial virus (RSV)
- Norovirus
- Human metapneumovirus (HMPV)
And looming over everything else is a separate—but deeply concerning—story: measles.
Measles: A Different Kind of Threat
While flu grabs most of the winter headlines, measles has been spreading at an alarming pace, particularly in South Carolina, where case counts have surged to levels not seen in decades. At last count, nearly 1,000 people have caught measles in 2026. That’s after only 6 weeks! In all of 2025 the number of measles cases was “only” around 330. Hundreds of people have been quarantined after exposure, and nearly all confirmed measles cases have occurred in unvaccinated individuals.
Measles is not just another rash illness. It is one of the most contagious viruses known, capable of lingering in the air for hours after an infected person leaves a room. Someone can spread measles several days before they realize they’re sick.
Even brief contact—an airport layover, a hotel stay, a crowded venue—can ignite a chain of infections that ripples across state lines.
Do You Need to Do Anything Differently Right Now?
If Influenza Isn’t Done, What Steps Can You Take?
- It’s still worth taking precautions, especially if you’re older, immunocompromised, pregnant, or caring for young children.
- Over-the-counter flu tests are readily available in most pharmacies, so please test if you feel sick!
- If you do test positive for flu, stay home! Missing work may be bad, but it’s better than spreading the flu.
- Improving indoor air quality and masking in crowded spaces remain effective tools—especially during a prolonged season like the one we seem to be in.
For measles:
- If you’ve had two doses of the MMR vaccine, you’re generally well protected.
- People who are immunocompromised or work in healthcare may need individualized advice.
- Anyone unsure of their vaccination status should check with their healthcare provider.
The Bottom Line:
This winter’s infectious disease landscape is crowded, unpredictable, and still evolving. Influenza isn’t done…it’s changing form and extending its reach. Measles is exploiting immunity gaps. And several respiratory and gastrointestinal viruses continue to circulate at high levels.
None of this means panic is warranted. But complacency isn’t helpful either.
We’ll continue tracking influenza and other outbreaks using multiple data sources. We do not just rely on the CDC’s weekly FluView reports. WastewaaterSCAN and local news reports are also useful sources we consult. Of course, we will keep sharing updates as the situation changes. When flu finally loosens its grip, we’ll happily report that too.
For now, influenza isn’t done! It’s just taking the long way out.
If you find our updates of value, please share them with acquaintances. They may want to know what is happening beyond the headlines. That’s what The People’s Pharmacy tries to provide…the stories that dig deeper than the health reports you see whiz past on your social media feeds.
We have been at this for more than 50 years. I (Joe) am a pharmacologist and Dr. Terry Graedon is a medical anthropologist. To learn more about us, please visit this link. If you would like to support our work, here is how you can do that. Thank you!
