A new type of vaccine against shingles can delay the onset of dementia, a new study at the University of Oxford shows. The best protective effect appears to be on women.
Even older types of shingles vaccines have been linked to protection against dementia, although not as strongly as the new vaccine. In the new study, approximately 100,000 older people who had received the new vaccine were compared to a similarly sized group of older people who had received the older vaccine, writes New Scientist.
The researchers saw that those vaccinated with the new vaccine had a 17 percent lower risk of developing dementia over the next six years than those vaccinated with the older vaccine.
The difference in effect could be explained by the fact that the older shingles vaccine Zostavax is based on live virus, while the newer vaccine Shingrix, launched in 2017, is an inactivated vaccine.
A possible explanation for why shingles vaccines can protect against dementia is that the herpes zoster virus, which causes shingles and chickenpox, also contributes to the development of dementia disease. The researchers say that the effect is statistically significant, but that more studies are needed to establish the link between shingles vaccines and delayed dementia disease.
According to Sören Andersson, unit manager at the Public Health Agency, it appears to be a very large and well-conducted study.
It strengthens previous findings that viral infections originating from the central nervous system, such as herpesvirus, can also lead to certain dementia diseases in the long run, he says.
