Shingles Vaccine Cuts Heart Attack Risk by 46% in New Study

An Unexpected Shield for the Heart

A vaccine designed to prevent a painful skin condition may also be one of the most powerful tools against heart disease. A large-scale study of nearly 250,000 American adults has found that the shingles vaccine reduced serious cardiac events by 46% and all-cause mortality by 66% in patients already at high cardiovascular risk — a protective effect researchers say rivals the benefits of quitting smoking.

The findings, presented at the American College of Cardiology's Annual Scientific Session (ACC.26) in March 2026, suggest that chronic inflammation driven by the dormant varicella-zoster virus may play a far larger role in heart disease than previously understood.

What the Study Found

Led by Dr. Robert Nguyen, a resident physician at the University of California, Riverside, the research analyzed data from 246,822 U.S. adults aged 50 and older diagnosed with atherosclerotic cardiovascular disease — a condition caused by plaque buildup in the arteries. Using the TriNetX health records database, the team compared 123,411 people who had received at least one dose of the Shingrix or Zostavax shingles vaccine between 2018 and 2025 with an equal number of unvaccinated individuals.

Within one year of vaccination, the results were striking:

• 46% reduction in major adverse cardiac events (MACE)
• 66% reduction in all-cause mortality
• 32% lower risk of heart attack
• 25% lower risk of stroke
• 25% lower risk of heart failure

Why a Shingles Vaccine Protects the Heart

Shingles, or herpes zoster, is caused by reactivation of the varicella-zoster virus (VZV) — the same pathogen behind chickenpox. After initial infection, VZV lies dormant in nerve tissue and can reactivate decades later, affecting roughly one in three people during their lifetime.

Scientists believe the mechanism linking shingles to heart disease involves inflammation and blood clotting. When VZV reactivates, it can trigger inflammation in blood vessel walls and promote clot formation — both key drivers of heart attacks and strokes. The nerve damage caused by shingles may also disturb cardiac rhythm, potentially leading to dangerous arrhythmias.

By preventing viral reactivation, the vaccine appears to eliminate this cascade of cardiovascular harm before it begins.

Building on Earlier Evidence

The ACC.26 findings do not exist in isolation. A systematic review and meta-analysis published in the European Heart Journal — drawing on data from over one million people — previously found that shingles vaccination was associated with a 23% lower risk of cardiovascular events overall and a 26% reduction in major adverse cardiovascular events. That study also showed protection lasting up to eight years, with the greatest benefit observed two to three years post-vaccination.

A separate South Korean nationwide study published in the European Heart Journal corroborated these findings, reporting that live zoster vaccination was linked to a 26% reduction in major adverse cardiovascular events and a 26% drop in heart failure risk.

What Comes Next

Experts caution that the ACC.26 study is observational, not a randomized controlled trial, meaning it cannot definitively prove causation. The analysis also focused only on outcomes within the first year after vaccination. Nonetheless, the consistency of evidence across multiple large studies — spanning different populations, vaccine types, and geographies — strengthens the case that the link is real.

The U.S. Centers for Disease Control and Prevention currently recommends two doses of the Shingrix vaccine for adults over 50 and immunocompromised individuals. If further research confirms the cardiovascular benefits, shingles vaccination could become a standard part of heart disease prevention — a paradigm shift that reframes a common vaccine as a dual-purpose lifesaver.