As flu season approaches, many New Zealanders are deciding whether to get a flu shot. Most people see the vaccine as protection against fever, aches, and fatigue. Reporting from RNZ shows it may also protect your heart.
RNZ’s Sunday Morning reports that epidemiologist Dr Michael Baker says the influenza vaccine reduces the risk of heart attacks and strokes. He says the virus can inflame and damage the heart. It also puts stress on organs and increases blood clotting. These effects raise the risk of serious events.
Flu and heart risk are closely linked
RNZ’s earlier reporting, citing the Immunisation Advisory Centre, supports this link. Heart disease and stroke cause about 12,000 deaths each year in New Zealand. Evidence since 2003 shows the flu vaccine can reduce the risk of heart attacks and strokes by about one-third.
Dr Philip Shirley from the centre told RNZ that the link has been known for decades. In severe flu seasons, heart attacks and strokes increase.
He said people with confirmed influenza have a much higher risk of a heart attack soon after infection. The risk can rise six to ten times in the first week.
How influenza affects the heart
The virus can move from the lungs into the heart. It can cause inflammation of the heart muscle. It can also enter blood vessels. This can disrupt plaque and block blood flow. That leads to heart attacks or strokes.
Severe influenza also affects the lungs. Poor oxygen levels force the heart to work harder. This puts extra strain on the body.
Dr Baker also notes that higher flu activity often matches a rise in heart attacks.
How the vaccine helps
The main protection comes from preventing influenza. Fewer infections mean fewer complications.
The vaccine may also reduce inflammation in the body. RNZ reports that studies show people who had a flu shot before heart surgery had lower signs of heart stress after the operation.
There is also evidence of a broader immune effect. Regular vaccination may strengthen the immune system. This can help the body respond better to other illnesses.
Dr. Baker says the vaccine’s effect can be similar to some heart medicines for people who get infected.
Who benefits most
Older adults and people with chronic conditions gain the most benefit. Some vaccines are better suited to older people, although not all are publicly funded in New Zealand.
Health experts say even healthy people should consider vaccination. A low baseline risk can still rise sharply after infection.
Covid-19 and ongoing risk
RNZ also reports that New Zealand is facing its largest Covid-19 wave in 18 months. The virus remains unpredictable and can spread at any time of year.
Like influenza, Covid-19 can increase the risk of heart attacks and strokes after infection. Long Covid remains a concern and can affect quality of life.
Prevention matters
The key message from RNZ reporting is clear. The flu vaccine does more than prevent illness. It reduces the risk of serious complications, including heart events.
Flu vaccines will soon be available across New Zealand. Health experts say vaccination can protect both general health and heart health.
