On January 22 I issued Flu Watch #5 and Outbreak Update #4. In it I noted that the CDC had reported that cases of influenza were trending downward. Many news reports then suggested that flu season may have peaked. But I asked a critical question: “Can we trust the numbers?” Turns out that we couldn’t. The data collection process is slower than I would like. And I worry about the CDC’s ability to stay on top of infectious outbreaks. On February 4, the New York Times announced: “U.S. Flu Cases Are Rising Again.” One of my go-to sources these days is the WastewaterSCAN Dashboard. It monitors sewage around the country and reports that both Influenza A and B are at “High” levels. Influenza B has been on an “Upward trend” over the last three weeks. To make matters worse, measles outbreaks are exploding, especially in South Carolina. So, in this Flu Watch #6 and Outbreak Update #5, I have to report that the trend is now up for: influenza, measles, COVID, respiratory syncytial virus (RSV), norovirus, and human metapneumovirus (HMPV).
America relies upon the CDC for information about infectious diseases. Every Friday we scrutinize the FluView data. But this report is always out of date because of the data collection and reporting lag. On January 30, 2026 the CDC reported an 18% increase in cases of flu. What will this week’s Fluview reveal?
Flu Watch #6 and Reports From Around the Country
My influenza analysis is no better than anyone else’s. But I do not rely upon the CDC data alone. That is why I always check WastewaterScan. Should you do so, You will see that over the last 180 days there has been a substantial uptick in pathogens such as RSV, SARS-CoV-2, influenza A and B, HMPV, and norovirus.
I also scan a variety of news sources. It looks like flu cases are still high in California, Oregon, Colorado, New Mexico, Texas, Louisiana, Kansas, Nebraska, Illinois, Iowa, Missouri, Mississippi, Alabama, Tennessee, Michigan, Ohio, South Carolina, North Carolina, Massachusetts, New Hampshire and Maine (boldface = the worst outbreaks).
The New York Times (Feb. 4, 2026) suggests that:
“…we are likely to see a second, smaller rise in cases in the weeks ahead, which tends to happen every year in late winter, and that the virus will continue to spread into the spring.”
What’s Out There in Flu Watch #6?
We were initially reporting most of the cases were influenza A (H3N2) subclade K. This virus was hitting young children very hard. They were ending up with really high fevers. Some experienced dehydration and seizures and were often admitted to pediatric intensive care units.
Now, though, there are also reports of influenza A (H1N1). Influenza B is also starting to surge. That is not entirely surprising. Type B flu tends to show up in February and hang around.
Speaking of lasting into spring…that is exactly what happened in Australia. Their spring runs roughly from September thru November. This past flu season, the Aussies experienced an early wave of type A (H1N1) and then a late wave of type A (H3N2).
Here is how researchers describe what happened “down under” (Eurosurveillance, Dec. 11, 2025):
“In 2025, influenza seasons in Australia and New Zealand were each prolonged due to the emergence of an influenza A(H3N2) variant of subclade K (formerly J.2.4.1)…The rapid rise of A(H3N2) influenza cases at the end of long influenza seasons in both Australia and New Zealand, provides evidence that the new subclade K virus variant is virologically fit and antigenically distinct from previously circulating H3N2 viruses.
“This is the first time that such a variant has emerged so rapidly and spread so widely towards the end of the season in Australia−New Zealand and has continued to circulate into summer in Australia. This is unusual for A(H3N2) viruses but has been seen previously on occasions in Australia with influenza B viruses.”
Flu Watch #6:
We may be experiencing just the reverse of the Australian experience: an early A(H3N2) outbreak followed by influenza B (Victoria lineage). In any case, if we follow the “down under” path, we could have an extended flu season this year. Please stay tuned for updates.
Measles is Getting Out of Control:
In Flu Watch #6 and Outbreak Update #4 I wrote that measles was a mess! Here is what has happened:
- On Dec. 22, 2025 I reported that there were 285 confirmed cases of measles in 2024.
- On January 20, 2026 CIDRAP (Center for Infectious Disease Research and Policy) reported:
- “In the past week, South Carolina officials have confirmed 212 new measles cases, raising the state total to 646 and threatening to overtake last year’s West Texas outbreak as the largest in decades in the United States.”
- On February 3, 2026 CIDRAP reported the South Carolina:
- “…outbreak total is now 876, after adding 29 more cases since January 30.”
So, South Carolina is a hot mess in my estimation. There are over 400 people in quarantine because of presumed exposure. No one knows how many others may have become infected, though. The overwhelming majority of the cases were in unvaccinated people. A small number were in partially vaccinated individuals. The measles-mumps and rubella vaccine normally involves two-shots, but some folks only manage to get vaccinated once.
Florida is also showing signs of measles spread. Ave Maria University is a Catholic college near Naples. It is now reporting 20 measles cases.
ICE immigration detention centers are confirming measles infections. One is Texas and the other is in Arizona. And an international traveler who visited Disneyland apparently brought measles along for the rides.
It only takes a few cases to create a widespread outbreak. That’s because the incubation period for measles is roughly one to two weeks. An infected person can start spreading the disease several days before the telltale rash appears. An infected person can easily transmit the Measles morbillivirus to lots of other people.
Researchers have categorized various pathogens for transmission risk. The big four that pose the greatest risk are, in order, measles, adenovirus (that causes colds), Mycobacterium tuberculosis (TB) and SARS-CoV-2 that causes COVID (Geoscience Frontiers, Nov. 2022). Even good ventilation may not prevent the spread of these four nasties.
Do You Need A Measles Booster Shot?
The standard advice is no…if you received two shots of the MMR (measles-mumps-rubella) vaccination. If you are immunocompromised, though, all bets are off. You might well need a booster. Healthcare providers may also need an MMR shot because of the growing risk of exposure. If you had measles as a child, you probably do not need a vaccination. Your immunity should last a lifetime.
Final Words From Flu Watch #6 and Outbreak Update #5:
The pathogens are out there just waiting to infect another human and keep spreading. They include:
- Influenza A (H3N2) subclade K
- Influenza A (H1N1)
- Influenza B (Victoria)
- Measles
- COVID
- RSV
- Norovirus
- HMPV
- Adenovirus
- Rhinovirus
We hope you can avoid getting sick this winter. We have done our best to keep you informed. If anything changes dramatically we will issue another Flu Watch and Outbreak Update. We will also be checking the CDC’s FluView, even though it is always a week or two behind what is actually happening in the real world.
To better protect yourself from all those nasty bugs just waiting to infect you, please take some time to listen to a couple of our free podcasts:
Show 1457: How to Strengthen Your Immune System for Cold and Flu Season
With flu season raging and colds making people sick, it’s time to strengthen your immune system. How about NEWSTART?
Show 1454: Stopping Airborne Viruses: Simple Steps to Cleaner Indoor Air
Cleaner indoor air is an important step to avoid viral infections. How can you achieve it at home or at work?
You may wish to sign up for our free podcasts by visiting any of these podcast providers:
You may also find our eGuide to Colds, Coughs & the Flu of value. In it we have lots of simple solutions for dealing with respiratory symptoms.
Did you find this Flu Watch #6 of value? If so, we would be very grateful if you would pass it along to friends and family members. Just scroll to the top of the page and click on one of the icons for email or social media. And please let us know how you have been faring this winter. Did you or anyone you know come down with influenza, COVID, a cold or some other infection? Please let us know how you are doing and your general location. Thank you for supporting our work.
Citations
- Dapat, C., et al, "Extended influenza seasons in Australia and New Zealand in 2025 due to the emergence of influenza A(H3N2) subclade K viruses," Eurosurveillance, Dec. 11, 2025), doi: 10.2807/1560-7917.ES.2025.30.49.2500894
- Miksezewski, A., et alk, "The airborne contagiousness of respiratory viruses: A comparative analysis and implications for mitigation," Geoscience Frontiers, Nov. 2022, doi: 10.1016/j.gsf.2021.101285
