PostHole
Compose
Login
Scientists identify new spinosaurid, Moderna flu shot back on track, universal inhaled vaccine shows promise
A surprising FDA reversal on Moderna’s mRNA flu vaccine, early promise from a universal inhaled vaccine, and a desert fossil find that is reshaping spinosaurid history.
February 23, 2026
Desert dino find, flu shot U‑turn, universal vaxx hope, air toxin warning
A surprising FDA reversal on Moderna’s mRNA flu vaccine, early promise from a universal inhaled vaccine, and a desert fossil find that is reshaping spinosaurid history.
By Kendra Pierre-Louis, Lee Billings, Fonda Mwangi & Alex Sugiura
[An image of a fossilized head crests of Spinosaurids mirabilis on sand]
Photo by Daniel Vidal/University of Chicago
[Illustration of a Bohr atom model spinning around the words Science Quickly with various science and medicine related icons around the text]
Apple | Spotify | YouTube |RSS
Kendra Pierre-Louis: For Scientific American’s Science Quickly, I’m Kendra Pierre-Louis, in for Rachel Feltman. You’re listening to our weekly science news roundup.
Let’s start off with a vaccine 180. In a sudden turn of events last Wednesday the U.S. Food and Drug Administration agreed to review Moderna’s new mRNA flu vaccine, according to the company. The announcement came roughly a week after Moderna revealed that the FDA had rejected its application.
The company said the agency originally called the plan for the vaccine’s phase 3 trials “acceptable,” But its position changed after top FDA official Vinay Prasad overruled the agency’s reviewers, according to STAT. Moderna’s press release about the rejection said the FDA had declared the company’s study not “adequate and well-controlled.” Angela Rasmussen, a virologist at the University of Saskatchewan, toldCIDRAP news that, quote, “The trial design they used is essentially the trial design that every single flu vaccine has used.”
On supporting science journalism
If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.
In the aftermath of the original refusal Bloomberg reported that Moderna’s chief executive officer, Stéphane Bancel, deemed the agency unpredictable. He said that if the FDA continues to behave this way it, quote, “threatens U.S. leadership in innovative medicines.”
Speaking of innovative medicines, a new studypublished last Thursday describes a single vaccine that could offer protection against multiple respiratory illnesses at the same time. An extra perk? The vaccine would be inhaled—no needles necessary.
The work, led by a Stanford University researcher and published in the journal Science, takes a novel approach to vaccines, which since their earliest days have relied on something called antigen specificity. That means they mimic a specific aspect of a pathogen to train what’s known as the adaptive immune system to recognize and fight off the infection—for example, COVID vaccines target the spike protein on the virus.
The adaptive immune system is our slower-acting, targeted defense mechanism. It also has memory so the next time we’re exposed to that pathogen we know how to fight it off—that’s one of the many benefits of this vaccine-development technique. But there are also drawbacks.
The pathogen can mutate quickly or a new pathogen can pop up, rendering the vaccine less effective—that’s what necessitates annual COVID and flu shots. And the specificity of this method means the vaccine only works against the targeted pathogen, creating a need for multiple vaccines.
But in this study, instead of focusing on mimicking aspects of viruses and bacteria, the researchers looked at the way immune cells communicate during an infection and imitated those signals. The goal was, in part, to trigger the innate immune system. Under normal circumstances it can take days or even weeks for the adaptive immune system to kick in, but the innate immune system contains rapid-response generalists that react to an infection in minutes. They are the body’s first line of defense against infection, but typically, that protection doesn’t stick around very long.
The researchers in this case developed an inhaled vaccine that is designed to stimulate both the adaptive immune system targeted by most vaccines as well as innate immune system cells in the lungs.
The vaccine was tested in mice, who were given different dosages and then exposed to COVID-19 along with other coronaviruses that cause illnesses like the common cold. Mice who received three doses a week apart fared much better than their unvaccinated peers. The researchers found that the vaccine effectively triggered the innate immune system and kept it running longer than normal. That drastically lowered the mice’s viral load, and any virus that snuck past was quickly greeted by a primed adaptive immune system. All of the vaccinated mice survived, while many of the unvaccinated ones did not.
The researchers also tested the mice with bacterial respiratory infections and found, again, that the vaccine provided protection. And there was another happy benefit: the mice also seemed to be less sensitive to respiratory allergies after inoculation.
There are some caveats to this study, namely, that the research was done on mice, not humans, and the protection lasted about three months. But it is a hopeful first step.
Also on the theme of breathing a study published last Tuesday in the journal PLOS Medicine suggests that exposure to air pollution can directly increase one’s chances of developing Alzheimer’s.
The study focused on a specific kind of fine particulate pollution called PM2.5, which refers to its maximum size of 2.5 micrometers, or roughly 30 times smaller than a strand of human hair. The tiny particles, which are often generated when we burn fossil fuels, have been linked to heart attacks and strokes. They’re also thought to be responsible for tens of thousands of premature deaths each year in the U.S.
An Emory University team looked at nationwide health data for roughly 28 million Medicare beneficiaries who were 65 or older between 2000 and 2018. The researchers then compared that data with individuals’ levels of PM2.5 pollution exposure. And while some of the conditions that are linked to PM2.5 are also risk factors for Alzheimer’s, the researchers found that this pollution exposure increased Alzheimer’s risk separately from those other comorbidities.
In a press statement they said, “We found that long-term exposure to fine particulate air pollution was associated with a higher risk of Alzheimer’s disease, largely through direct effects on the brain rather than through common chronic conditions such as hypertension, stroke, or depression.”
[...]