Archive · 31 Oct 2025
New Study: Viral Infections Like COVID-19 and Flu Significantly Increase Heart Attack Risk
Imagine your body is like a castle, and viruses are invaders.
When invaders attack, your castle's defenders (your immune system) go into high alert, causing lots of activity and even some minor damage to the castle walls to fight them off.
This is called inflammation.
Sometimes, after the invaders are gone, the defenders stay on high alert for a while, and this continued activity can harm the castle's important pipes (blood vessels) and the castle's main engine (the heart).
New research shows that infections like COVID-19 and the flu can make your heart more likely to have problems, like a heart attack, even after you start feeling better.
This is because the inflammation can make it harder for blood to flow and can damage the pipes.
Getting vaccines for these illnesses can help calm down the defenders and lower the risk of heart problems.
It's important to talk to your doctor about getting vaccinated to keep your heart safe.
Viral infections like COVID-19 and the flu can significantly increase the risk of heart attacks and strokes.
People are up to four times more likely to have a heart attack and five times more likely to have a stroke within weeks of influenza infection.
COVID-19 increases the risk of heart attack and stroke by three times within 14 weeks, with the risk remaining elevated for up to a year.
Chronic infections such as HIV and hepatitis C are also linked to long-term cardiovascular risks.
Vaccinations against viral infections, such as flu shots, can reduce the risk of heart complications.
- Who
- Researchers from UCLA led by Dr. Kosuke Kawai
- What
- A meta-analysis of studies found that viral infections like COVID-19 and the flu significantly increase the risk of heart attacks and strokes.
- When
- Within weeks to up to a year after infection, depending on the virus.
- Where
- The research was published in the Journal of the American Heart Association.
- Why
- Viral infections trigger inflammation and clotting, which can damage blood vessels and strain the heart, even after the acute infection has passed.
- Study Publication
- Journal of the American Heart Association
- Lead Researcher
- Dr. Kosuke Kawai, UCLA
- Meta-analysis Size
- 155 high-quality studies
- Post-Influenza Heart Attack Risk
- 4 times higher within 1 month
- Post-COVID-19 Heart Attack Risk
- 3 times higher within 14 weeks, elevated for up to a year
- HIV and Heart Attack Risk
- 60% increase
- Flu Shot Benefit
- 34% lower risk of cardiovascular events