According to a report by the Daily Mail UK, newly published peer reviewed research has found a small but measurable increase in the short term risk of shingles following Covid booster vaccination, raising attention on a viral reactivation that has been linked in separate studies to dementia and other brain health concerns.
The study, published in the journal Drug Safety on December 11, analyzed electronic health records from more than two million people aged 12 and older who received at least one Covid vaccine. The analysis focused on the incidence of shingles within 28 days after vaccination.
Results showed that the risk of developing shingles within 28 days increased by seven percent when all vaccine doses were combined and by 21 percent after a third or booster dose of an mRNA vaccine. Among men of all ages, a significantly higher risk was observed after vector based vaccines, with a 38 percent increase reported.
Shingles is caused by the varicella zoster virus, which remains dormant in the body after childhood chickenpox and can reactivate later in life. The condition typically presents as a painful, blistering rash and is more common in older adults and individuals with weakened immune systems.
The temporary rise in shingles cases was linked to short term changes in immune function following vaccination. The study noted that immune cells involved in controlling latent viruses may be briefly reduced or less active after vaccination, allowing the virus to reactivate.
The findings do not prove that Covid vaccines cause shingles. The reported increase in risk was described as small, temporary, and limited to certain subgroups, with most cases treated in general practice rather than requiring hospitalization.
Separate long term research has shown that adults aged 50 and older who were hospitalized with shingles were more likely to later develop dementia. Another study spanning more than two decades found that shingles was associated with higher rates of early onset dementia, with the greatest risk observed among individuals aged 50 to 65.
The study also noted contrasting findings across regions. Data from Hong Kong showed a sharp increase in shingles hospitalizations shortly after Pfizer BioNTech vaccination, while a separate US study using healthcare claims data found no increased risk after Covid vaccination and reported rates comparable to those seen after flu shots.
Most participants received two vaccine doses. Pfizer BioNTech accounted for about 69 percent of all doses administered, followed by Moderna at 18.6 percent. The median age of participants was 51, and the most common underlying conditions were cardiovascular disease and chronic lung disease.
Further research was cited as necessary to clarify the relationship between vaccination, shingles reactivation, and long term neurological outcomes, particularly among older adults.
