Let’s start with the bad news.
There’s a decent chance, perhaps as high as 11 percent if you’re unvaccinated, that some time over the course of this winter, you’ll be overcome with chills, followed by extreme fatigue, body aches and cough, and culminating in a sudden spike in fever. Congratulations: you have the flu.
Every winter in the US has its share of flu cases, but this season is shaping up to be particularly bad. Early this week the Centers for Disease Control and Prevention put the flu season in the “moderately severe” category, with an estimated 11 million illnesses, 120,000 hospitalizations, and 5,000 deaths so far. Here in New York, where I live, the city kicked off 2026 by setting records for flu-related hospitalizations.
While what we’re experiencing is not a “super flu,” it is a particularly bad one, thanks in part to the emergence of a subgroup of the well-established H3N2 flu virus called subclade K. It carries a bunch of mutations that seem to have rendered the current flu vaccine somewhat less effective. (Though far from completely ineffective — more on that below.) Nor does it help that only around 44 percent of US adults have taken the flu shot so far, well below vaccination rates before the Covid pandemic. The decline has been particularly sharp for children, who are more vulnerable to the flu, which has resulted in higher than normal pediatric hospitalizations.
As bad as this season is shaping up to be, chances are most of us will suffer through it and then forget until the next year comes around. After all, it’s just the flu, right? But even normal influenza is far more than just a seasonal nuisance. The World Health Organization estimates that there are around 1 billion flu infections in a given year, which can lead to as many as 5 million severe cases and up to 650,000 flu-related respiratory deaths per year, mostly among the very young and the very old.
The burden of flu goes beyond those numbers: CDC research indicates that flu infections can raise the risk of heart attacks and strokes. Plus all those sick days add up to as much as 111 million lost work days in the US alone, while childhood infections lead to more school absences and a knock-on effect for parents forced to stay home.
Oh, and chances are decent that the (inevitable) next global pandemic will come from a mutant flu virus, just like past pandemics in 2009, 1968, 1957, and the granddaddy of them all, 1918, which killed at least 50 million people around the world.
So that’s the bad news. The good news? There are ways to protect yourself right now — and even more promising, glimmers on the scientific frontier of a world without flu.
What works — and what doesn’t — with the flu shot
The simplest way to keep safe is, of course, to get your flu shot. Like right now — even though the flu season is well underway, it’s worth getting your shot if you haven’t yet. Early data from the UK found protection rates against hospital admission of 70 to 75 percent for children and 30 to 35 percent in adults. That’s normal: The standard flu vaccine isn’t great at preventing cases, but it is very effective in reducing the severity of illness. Throw in the fact that you can now easily get an at-home flu test and secure the antiviral Tamiflu early in an illness, and you do have the power to ensure your case is milder.
But it is true flu shots are not our most effective class of vaccine. That largely has to do with the nature of the flu, and how the shots are made.
Influenza is what you might call a “promiscuous” virus. Strains are constantly evolving, and can easily swap genetic material through a process called reassortment to create new, potentially more dangerous viruses. Because of that, international health officials have to create a new vaccine strain every year, hoping that it will match the strain actually circulating months later when vaccines are available for distribution.
If the dominant strain changes during those months, the vaccine will be less effective. And any vaccine that has to be taken over and over again on an annual basis is going to be a harder sell to the public, even before taking into account rising anti-vax sentiment.
There’s already progress being made to reduce the time between when a vaccine strain is selected and when it can be produced, chiefly by using rapid mRNA platforms rather than growing vaccines in eggs, as has been done for decades. But even better: What if it were possible to create a flu vaccine that was effective against a wide variety of different flu strains?
The dream of a universal flu vaccine
A “universal” flu vaccine is one that would be at least 75 percent effective against influenza A viruses and provide durable protection for at least a year (though ideally longer). In other words, it would be a vaccine that would act more like the almost perfectly protective measles vaccine and less like, well, a flu shot.
Such “universal” flu coverage would not be one single breakthrough, but a portfolio of strategies for outsmarting a virus that mutates faster than our annual vaccine calendar. The first bucket is universal (or universal-ish) vaccines: instead of training antibodies mainly against flu’s fast-changing hemagglutinin (HA) “head,” researchers are trying to steer immunity toward viral targets that mutate less.
One major approach focuses on the HA stem or stalk, a region of the virus that changes more slowly; early human trials of stem-focused designs suggest these vaccines can be safe and elicit broadly reactive immune responses. Another vaccine strategy uses mosaic/nanoparticle displays that present HA antigens from multiple strains at once, aiming to teach the immune system to recognize flu’s common features rather than this year’s exact variant; the government’s FluMos program is an example now in early clinical testing.
A third line leans on broader immune mechanisms: targeting neuraminidase (NA) (the N in HN flu viruses), or boosting T-cell responses to internal proteins that rarely change, which may not always prevent infection but could make illness far less severe when the virus drifts.
There’s also the “universal without a vaccine” lane: prevention and treatment that don’t depend on your immune system’s memory. Cidara, a San Diego-based biotech company, has developed a long-acting preventive designed to provide season-long protection by chemically linking multiple copies of a neuraminidase inhibitor to a long-lasting antibody. Preclinical work has shown broad resistance to influenza A and B, and the company’s approach is promising enough that it is now in the process of being acquired by pharma giant Merck.
Even more sci-fi: using gene editing to create all-purpose flu treatments. Scientists in Australia are working on using the gene editing tool Crispr to develop an antiviral nasal spray that could shut down a wide variety of flu viruses.
We shouldn’t have to live with the flu
Historically, the US hasn’t allocated nearly enough money to universal flu prevention research, though in May the Trump administration surprised scientists with plans to spend $500 million on an approach that relies on older vaccine technology. Except in those rare years when a flu pandemic boils over, we tend to treat flu as something we just have to suffer through.
But hundreds of thousands of people globally each year won’t survive their bouts with the flu, and millions more will suffer because of the viruses. We’ve managed to all but knock out past killers like smallpox, the measles, and the mumps (Well, provided we agree to take our vaccines.) There’s reason to believe that influenza can be next.
A version of this story originally appeared in the Good News newsletter. Sign up here!
