The future of vaccination and disease prevention
A woman came to my counter last winter holding a leaflet about the shingles vaccine. She was not worried about shingles. She had read somewhere that the same jab might lower her chances of dementia, and she wanted to know whether it was true or whether it was another thing the internet had decided to believe.
I gave her the honest answer, which happens to be the most interesting answer I get to give at the moment. We are not certain yet. But the evidence is certainly pointing in that direction.
That conversation is the reason I wanted to write this. Because if you zoom out, vaccination is quietly becoming one of the most exciting stories in the whole of preventative health, and almost nobody is talking about it with the attention it deserves.
How we got here
The whole idea started with a hunch about milkmaids. In 1796, Edward Jenner noticed that dairymaids who had caught cowpox seemed to be spared the horror of smallpox. He tested the idea, deliberately exposing a young boy to cowpox and then to smallpox, and the protection held. The word vaccine comes from vacca, the Latin for cow. That is how recently we worked out the single most powerful preventative tool in medical history.
It took the best part of two centuries to finish the job Jenner started, but in 1980 the World Health Organization declared smallpox eradicated. A disease that killed an estimated 300 million people in the twentieth century alone simply stopped existing in the wild. It remains the only human disease we have ever wiped off the face of the planet, and we did it with a vaccine.
Polio looked like it would be the second. A global eradication programme launched in 1988 has cut cases by more than 99 percent, and wild poliovirus is now endemic in only two countries, Afghanistan and Pakistan [1]. That last stretch has proven stubborn, because the hardest part of eradicating anything is the final few cases in the hardest places to reach. We are close. We are not finished.
Then came the chapter every pharmacist remembers, because we are still living with its consequences. In 1998, a paper in The Lancet suggested a link between the MMR vaccine and autism. The work was later found to be seriously flawed, the paper was retracted, and its lead author was removed from the medical register. The science was clear that no such link exists. But the fear had already left the building. Vaccination rates dropped, measles returned to countries that had nearly seen the back of it, and trust took a beating that it has never fully recovered from. I mention it not to relitigate an old fight, but because it taught everyone in public health a lesson that still matters. A vaccine only works if people are willing to have it, and willingness runs on trust. Hold that thought, because it comes back.
Which brings us to the most extraordinary recent example of all. When COVID-19 arrived, the genetic sequence of the virus was shared in January 2020. A vaccine was going into arms in the UK by December of the same year, the first country in the world to roll out an authorised jab. Compressing a decade of development into roughly twelve months sounds like a corner was cut somewhere. It was not. The safety phases still happened, they simply ran alongside each other instead of one after another, backed by money and global urgency on a scale we had never seen. The mRNA technology that made it possible had been quietly worked on for decades, waiting for its moment.
I realise these claims about the COVID-19 vaccines draw strong reactions in certain corners of the internet. There are people who believe the vaccine left them with severe or lasting illness, and I am not going to wave those concerns away. There was real evidence linking the AstraZeneca vaccine to a rare but serious clotting problem, serious enough that several countries changed how and in whom they used it. But this truth still holds - these vaccines saved millions of lives around the world.
So that is the story so far. A hunch about cows, one disease eradicated, another almost there, a crisis of trust, and a pandemic that proved how fast we can move when we have to. Now for the part that genuinely excites me.
When a vaccine does more than you bought it for
Let me go back to that woman and her leaflet.
There are two shingles vaccines. The older one is a live vaccine called Zostavax. The newer one, called Shingrix, is a recombinant vaccine given as two doses, and it is the one most people in the UK are offered now. Both protect against shingles, which is reason enough to have it when you are eligible. The interesting bit is what researchers noticed almost by accident.
In Wales, eligibility for the older shingles vaccine was decided by date of birth. If you were born just before a cut off date you could not have it, and if you were born just after, you could. That accidental rule created something researchers dream about, a clean natural experiment where the two groups were almost identical except for the vaccine. When a team led by Stanford analysed the health records, the people who received the vaccine were around 20 percent less likely to be diagnosed with dementia over the following seven years. The findings were published in Nature in 2025 [2].
Here is why that matters more than the usual health headline. Most studies of this kind cannot tell you whether the vaccine caused the lower risk or whether healthier people simply tend to get vaccinated. The date of birth quirk strips a lot of that bias away, which makes this one of the strongest signals we have seen that a vaccine might protect the brain. And it is not alone. The newer recombinant vaccine has been linked to lower dementia risk too [3], and a follow up study in 2025 suggested the benefit might even extend to people already living with the disease [4]. There are early signals on the heart as well, with some analyses associating shingles vaccination with fewer cardiovascular events, though that evidence is younger and needs more work [5].
So, evidence or hype? This is the honest verdict. Several independent datasets are now pointing in the same direction, which is exactly what you want to see before getting excited. But association is not the same as proof of cause, and we do not yet fully understand the mechanism. The leading theories are that the virus behind shingles may quietly damage the nervous system over time, or that these vaccines nudge the immune system in a generally protective way. Both are plausible. Neither is confirmed. What I told the woman at my counter is what I will tell you. Have the shingles vaccine because it prevents shingles, which is miserable in its own right. Treat any protection for your brain as a possible and very welcome bonus that the science is still working hard to pin down.
The vaccines being designed by machines
Now for the frontier.
The slowest part of designing a vaccine has always been working out the shape of a protein. Proteins fold themselves into complicated three dimensional shapes, and that shape decides what they do and how your immune system might recognise them. Working out a single protein shape in a laboratory could take years.
Then artificial intelligence solved a problem biologists had wrestled with for half a century. A system called AlphaFold, built by the team at DeepMind, learned to predict protein shapes in minutes rather than years. The achievement was significant enough that its creators were awarded the Nobel Prize in Chemistry in 2024. The latest version can also predict how proteins interact with other molecules, which is precisely the kind of thing you need to know when designing a vaccine [6].
What this unlocks is the ability to design the active part of a vaccine on a computer before anyone touches a test tube. I want to be careful here, because this is where excitement tends to outrun reality. AI speeds up the design stage. It does not abolish clinical trials, which still take years to prove a vaccine is safe and that it works in real people. The machine gives you a much better starting point. It does not give you a finished product.
But the proof that this approach is real arrived only this month, and it is a British story. Researchers at the University of Cambridge and a spinout company called DIOSynVax have just completed the first human trial of a vaccine whose active ingredient was designed entirely by computer. It is aimed at the family of coronaviruses that includes the one behind COVID-19, along with related viruses still circulating in bats that could one day spill over into humans. Rather than targeting a single strain, the AI was asked to design a shared target common to the whole family, the idea being to protect against future threats before they even emerge. In the trial of 39 volunteers, delivered without a needle using a fine jet, the vaccine was safe and produced an immune response not only against COVID-19 and SARS but against those bat viruses too. The results were published in 2026 [7].
It is early. This was a first in human safety trial, not proof that it will stop people getting ill, and there are years of work ahead. But it is the first real demonstration of an entirely new way of building vaccines, and the fact that it happened in the UK is something to be quietly proud of.
When prevention reaches into your DNA
The last idea on the horizon stretches the word vaccine almost to breaking point, so let me be precise about what it actually is.
A classic vaccine trains your immune system to recognise a threat. The newer idea is different. It is a one time treatment that switches off a faulty gene driving your lifelong risk of a disease. It is not a vaccine in the textbook sense at all. People reach for the word because it shares that same appealing quality, one dose, durable protection, given before the problem starts. Researchers themselves have started describing these treatments as vaccine-like.
One distinction matters more than any other here, and it is the kind of thing I would want you to understand before anyone tries to sell you on the idea. These treatments edit the genes in your own cells, often in the liver. They do not change the genes you pass on to your children. This is your risk being rewritten, not your family line. That is an important scientific and ethical line, and it is worth knowing it is there.
Take the heart first, because it is furthest along. There is a particle in the blood called lipoprotein(a), and the amount you carry is largely fixed by a gene called LPA. A high level raises your risk of heart attack and stroke, and until very recently there was no medicine that lowered it directly, although several are now in trials. A treatment called CTX320 uses gene editing to switch down the LPA gene in the liver. In studies in monkeys it reduced lipoprotein(a) by around 95 percent, and it has now moved into early human trials [8].
The brain is the bolder frontier, and it is much earlier. The strongest common genetic risk factor for late onset Alzheimer's is a version of a gene called APOE, specifically the variant known as APOE4. What makes it such a tempting target is that APOE4 differs from a lower risk version of the same gene by a single letter of DNA. In theory you could edit that one letter and move someone towards the safer version. For now this work sits in mice and in cells in a dish, not in people [9].
Evidence or hype? Both, depending on where you look. The cardiovascular editing is real, moving quickly, and already in humans. The dementia editing is promising but much earlier in the journey. And across all of it sit enormous open questions about long term safety, edits landing in the wrong place, how you deliver it, what it costs, and who gets access. Promising is not the same as proven, and the gap between the two is where careful people live.
What this means for you, today
Here is the quiet tension running underneath the whole story. We are building the most sophisticated vaccine technology in human history and rolling it out into one of the least trusting moments for vaccines in living memory. Remember that woman with her leaflet, and remember the damage one flawed paper did in 1998. The science is racing ahead. Trust is the part that lags behind, and trust is the part I think people like me can actually do something about.
The science fiction stuff is coming, and faster than you would think. AI designed vaccines, one dose treatments that rewrite your risk, jabs that might guard your brain as well as your body. I find it genuinely hopeful. But the prevention available to you right now is still doing most of the heavy lifting, and most of it is unglamorous. The vaccines you already qualify for, taken when you are offered them. The fundamentals of sleep, movement, food, stress and connection, done steadily rather than perfectly. The future will build on the foundation you lay today, not instead of it.
So here is the one practical thing to do this week. Find out which vaccines you are actually eligible for at your age and stage, from the flu jab to the shingles vaccine, and stop treating them as optional admin. They are the cheapest, most proven prevention you will ever be offered, and you do not have to wait a decade for them.
The science of staying well is moving faster than at any point in my lifetime. The smartest thing you can do is give your future self the best possible starting line, and then let the breakthroughs find you already healthy.
If you want me to keep translating this stuff as it lands, calmly and without the hype, the newsletter is where I will go deeper. I have not yet launched it but sign up below and I will see you there soon.
Stay healthy,
Jake Dose of Longevity
References
World Health Organization. Statement of the forty-fourth meeting of the Polio IHR Emergency Committee. Geneva: WHO; 2026.
Eyting M, Xie M, Michalik F, Heß S, Chung S, Geldsetzer P. A natural experiment on the effect of herpes zoster vaccination on dementia. Nature. 2025;641(8062):438-446.
Taquet M, Dercon Q, Todd JA, Harrison PJ. The recombinant shingles vaccine is associated with lower risk of dementia. Nat Med. 2024;30:2777-2781.
Xie M, Eyting M, Bommer C, Ahmed H, Geldsetzer P. The effect of shingles vaccination at different stages of the dementia disease course. Cell. 2025;188(25):7049-7064.
Dehghani A, et al. Herpes zoster vaccination and the risk of dementia and major cardiovascular events. Presented at IDWeek 2025 (conference presentation).
The Royal Swedish Academy of Sciences. The Nobel Prize in Chemistry 2024: computational protein design and protein structure prediction (AlphaFold). 2024.
Munro APS, Ferrari M, Kinsley R, et al. A phase I, needle free, dose escalation clinical trial of pEVAC-PS, a candidate pan-Sarbecovirus vaccine. J Infect. 2026;92(6):106759.
Gene therapy and genome editing for lipoprotein disorders [review]. Eur Heart J. 2025;46(35):3420.
Optimized prime editing of the Alzheimer's disease associated APOE4 mutation. Stem Cell Rep. 2025;20(1):102372. Focused ultrasound mediated APOE ε4 knockdown in mouse brain. Alzheimers Dement. 2025. doi:10.1002/alz.70464.
