‘I want to do everything I can to head off dementia’: why demand for the shingles vaccine is soaring

When Jenny, a 50-year-old marketing and branding professional from Cambridge, went for her shingles vaccine last year, an entirely different disease was on her mind. Having witnessed three of her four grandparents succumb to dementia, with all the distress that brought, she wants to avoid the same fate. She hopes the shingles vaccine might help.Jenny is far from alone. Britain’s high street chemists have reported a rise in demand for the shingles vaccine, at least some of which is driven by people more worried about dementia than shingles. And while the vaccine is free for some on the NHS, most under-65s pay around £450 for the full two doses.The trend follows a flurry of studies that suggest, but do not prove, that the shingles vaccination might offer some protection against dementia. How much protection? It depends on how the study is done, but scientists have reported as much as a 20% reduction in risk, with the strongest effects in women. On a brutal disease that has no cure, the impact could be profound. “Imagine a vaccine that became a medicine for dementia,” says John Todd, professor of precision medicine at the University of Oxford and one of the scientists involved. “Wow. Wouldn’t that be amazing?”Recent figures from Boots show that bookings for its shingles vaccination service more than doubled over the past year, after rising 30% in the year before. A similar trend has played out at Superdrug, where bookings are up 41% year on year.Of course, many who go for their shots simply want to avoid shingles. It’s a painful rash, triggered by reactivation of the chickenpox virus which lies dormant in the nervous system after a childhood infection. The vaccine is not approved for any other condition. But dozens of people who contacted the Guardian said preventing dementia was at least part of their reason for getting the shots.“I want to feel as if I’ve done everything I can to try to head it off, in terms of risk factors and preventive measures that are available to me now,” says Jenny. “If there’s a potential for this to give me more time without the onset of dementia in 20 years’ time, then God, I’ll take it.”Nearly 60 million people live with dementia globally, but the figure is set to rise with population growth and ageing. By 2040, more than 100 million people are projected to have the disease. In England and Wales, it’s expected dementia could affect 1.7 million people that year, with the annual cost reaching £90bn.Nearly 60 million people live with dementia globally, but the figure is set to rise. Photograph: Posed by models; Jessie Casson/Getty ImagesThe most common form of dementia, Alzheimer’s disease, is associated with the abnormal buildup of proteins in the brain. Plaques (clusters) of amyloid accumulate between neurons, and tangles of another protein, tau, form inside the nerve cells. New drugs can clear amyloid plaques and slow the disease, but so far the impact on patients appears small and the side-effects can be serious.The wave of work on the shingles vaccine was spurred by suspicions that the virus that causes chickenpox and shingles, varicella zoster virus or VZV, might somehow contribute to dementia. After a chickenpox infection, some virus remains in the body, lying dormant in neurons. As the immune system weakens with age, or is suppressed through medications or stress, the virus can reactivate and travel down nerve cells to the skin where it causes shingles. In the brain, the virus can drive inflammation, nerve cell stress and the accumulation of amyloid and tau.In an influential paper in Nature last year, researchers at Stanford University in California focused on a natural experiment that arose in Wales during a shingles vaccination programme. The vaccine on offer, Zostavax, was a live-attenuated vaccine, meaning it contained a weakened version of the varicella zoster virus. It was made available from 1 September 2013, but anyone who was 80 or older on that day was ineligible, because it becomes less effective the older a person gets.The age-related cutoff split the older population into two groups: those who could get the vaccine and those who could not. This allowed scientists to compare dementia rates in thousands of people born on different sides of the eligibility line.When the Stanford team ran the numbers, they found that dementia rates were 8.5% lower in the vaccine-eligible group over seven years, in women, but not in men (the gender disparity in this experiment remains unexplained). Since only about half of the group went along for their shots, the researchers concluded that the vaccine lowered dementia risk by nearly 20%. They have since reported similar effects in Australia and Ontario, Canada.“We have a really compelling body of data from these studies,” says Pascal Geldsetzer, an epidemiologist on the Stanford studies. “We’re much more confident that what we’re looking at is cause and effect rather than just correlation.”More evidence came in 2024 from the University of Oxford, when Todd teamed up with psychiatrists Maxime Taquet and Paul Harrison to study Shingrix, a newer and more potent shingles vaccine that has largely replaced Zostavax. Shingrix is not a live-attenuated vaccine but contains viral proteins and an adjuvant – an additive designed to strengthen the body’s immune response and so make the vaccine more effective. In this case, the adjuvant is made of tiny fat-based particles called liposomes that are filled with various compounds that stimulate different parts of the immune response.Shingles is triggered by reactivation of the chickenpox virus which lies dormant in the nervous system after a childhood infection. Photograph: Posed by models; Milan_Jovic/Getty ImagesThe Oxford team analysed health records for more than 200,000 US citizens who were vaccinated for shingles. About half had Shingrix and half Zostavax. Over the next six years, dementia cases were 17% lower in those who had Shingrix compared with Zostavax, amounting to an extra 164 days lived without the condition. Women fared better, with a 22% lower risk compared with 13% for men. (Women have a higher dementia risk, which seems mostly down to them living longer.) One benefit of the study was that it compared Zostavax v Shingrix rather than vaccinated v unvaccinated people. That reduced the risk of the results being skewed by the “health vaccinee” bias, whereby people who get vaccinated are generally more health conscious and do more to reduce their risk of dementia in other ways.“I thought wow, I’ll just book the vaccine online,” says Todd. “If by chance it does lower the risk of dementia, I’m 68 – why wouldn’t I take that? And also, it’s really effective against shingles.” Todd is a consultant for GSK, the manufacturer of Shingrix, but the company had no involvement in any of the studies.More recent work hints at other potential benefits of the vaccine. In August, the Oxford team published a paper showing a reduced risk of heart attacks and stroke after the Shingrix vaccination. The effect is small, but across the population it could prevent thousands of deaths per year. Separate work at Kaiser Permanente, the US healthcare giant, found a similar effect.The results are exciting, but none of this is proof. Critical questions remain. In July, researchers at the University of Bristol, and others including Geldsetzer, found no evidence in much larger English hospital records that Zostavax protects against dementia. That may be due to quirks in the data or how it is analysed, or a sign that the old Zostavax vaccine does not protect against dementia after all. Geldsetzer suspects hospital data is not the best for studying dementia, as most patients are managed in primary care.Precisely how the vaccine might protect against dementia is still a puzzle. By stimulating the immune system to attack VZV, the vaccine might help to reduce inflammation and cellular damage in the brain. There may be knock-on effects whereby inflammation reactivates another dormant virus, the cold sore-causing HSV1, which in turn drives Alzheimer’s-like damage. The vaccine may also have broader effects, boosting ailing immune systems so they are better at clearing harmful waste from the brain.One avenue scientists are exploring is whether the adjuvant, which is in Shingrix but not Zostavax, is important for protection against dementia. The Oxford team suspect that might explain why a vaccine for respiratory syncytial virus, RSV, which contains the same adjuvant as Shingrix, also appears to protect against dementia. The adjuvant specifically stimulates T-cells that are central to the immune response to the virus. “You want a really healthy immune system to do the garbage collection of damaged neurons,” says Todd.The lack of hard proof hasn’t stopped people taking action. Jenny had already had a bout of shingles – “It looked like I’d been slapped across the face by a zombie,” she says – but it was the fear of dementia that prompted her to get vaccinated. She made the decision after reading the research for herself, wary that the press might have hyped it.Precisely how the vaccine might protect against dementia is still a puzzle. Photograph: Andrew Brookes/Getty Images/Connect ImagesSally, a 68-year-old former headteacher in Telford, Shropshire, cared for her mother with dementia for five years. “It does bring you up very sharply when you’re considering your own future,” she says. Sally runs marathons, watches her nutrition carefully and does all she can to protect herself from the disease. “I was going to have the shingles jab anyway, but when I saw the research saying there may be a protective effect against dementia, I jumped at it. The experience of caring for someone who developed dementia was pivotal in my decision.” She got the jabs on the NHS.It could be a while before we have clear answers. Todd and colleagues want to do a mechanistic study to understand at the deepest level what happens to the immune system when people have the shingles vaccination. Meanwhile, two major clinical trials are under way in Finland and Denmark to see whether Shingrix genuinely protects against dementia, but they won’t report for years.What should people do in the meantime? Geldsetzer says that while vaccine recommendations are a matter for government advisory bodies, he wouldn’t discourage people who want to get the shingles vaccine for dementia protection. Todd says: “I have been suggesting to friends and colleagues to get the vaccine if they are 50 or over – it’s safe.”Alzheimer’s Research UK does not advise people to have the shingles vaccine specifically to prevent dementia. Instead, it recommends all the healthy habits we know promote brain health: exercise, a good diet and challenging the brain throughout life. Michael Jones, evidence manager at the charity, says: “While new studies finding these links are promising and growing in number, there isn’t enough data to demonstrate a direct cause-and-effect relationship.”Dominic, a 61-year-old engineer in Christchurch, Dorset, paid for the Shingrix vaccine last year. His father had shingles, the classic rash around the torso, which lasted for months. His eldest sister had shingles, too. It affected her eye and caused minor damage. A cousin also developed the condition. Dominic planned to get the shot, but only acted after reading the dementia research. “I really don’t want to get shingles,” he says. “That could strike at anytime. And when does dementia start? We just don’t know, do we?”