Scientists have found that the risk of shingles may rise slightly in the weeks following a Covid booster shot.

The discovery comes from researchers at the University of Groningen in the Netherlands, who analyzed electronic health records from more than two million people aged 12 and older who had received at least one Covid vaccine.

The study found that the risk of developing shingles within 28 days of vaccination increased by seven percent when all doses were combined and by 21 percent after the third, or booster, dose of an mRNA vaccine.

Shingles, which appears as a painful, blistering rash, is caused by the varicella-zoster virus, which most people first encounter in childhood as chickenpox.

Separate research found that adults aged 50 and over who were hospitalized with shingles were seven times more likely to develop dementia.

Among men of all ages, researchers found a significantly higher risk of shingles after receiving a vector-based vaccine, with a 38 percent increase.

The authors noted that the increase in shingles risk after a booster mRNA dose is small, temporary, and limited to certain subgroups, and most cases are treated in general practice rather than requiring hospitalization.

The study comes as the FDA is drawing up plans to put a ‘black box’ warning on Covid vaccines, the agency’s most serious warning over potential side effects, reports suggested