Shingles Vaccine: A Surprising Tool for Biological Youth in Older Adults

Shingles, also known as herpes zoster, is caused by the reactivation of the chickenpox virus, which can lie dormant in the body for decades. It leads to a blistering rash and can result in long-lasting nerve pain, called post-herpetic neuralgia. The risk rises with age as the immune system weakens. “This study adds to emerging evidence that vaccines could play a role in promoting healthy ageing by modulating biological systems beyond infection prevention,” said Jung Ki Kim of the University of Southern California, the study’s lead author. A person’s biological age reflects how well their body is holding up as the years tick by. The team measured several aspects, including inflammation in the body, which tends to increase over time. They also looked at two measures of genetic ageing. The first, known as epigenetic ageing, refers to chemical tags that over time become attached to a person’s DNA, altering the activity levels of the genes encoded by that DNA. The second, called transcriptomic ageing, looks at how genes are copied into RNA, a step needed to make the proteins that keep cells working. On average, vaccinated participants had lower levels of chronic inflammation, slower rates of epigenetic and transcriptomic ageing, and a better overall biological ageing score. Chronic, low-level inflammation is thought to drive many diseases of later life, from heart disease to frailty and cognitive decline, a process sometimes called “inflammageing”. “By helping to reduce this background inflammation, possibly by preventing reactivation of the virus that causes shingles, the vaccine may play a role in supporting healthier ageing,” Kim said. The study was observational, meaning it cannot prove that vaccines directly cause the body to age less rapidly. The results may reflect the “healthy user effect”, where people who choose to get vaccinated tend to be in better shape, wealthier and more engaged with healthcare generally. However, people vaccinated four or more years before their blood was taken still showed slower biological ageing than those who had never been vaccinated. The findings were published in The Journals of Gerontology.