Respiratory infections, vaccinations and your heart

In otherwise healthy people, respiratory infections usually involve mild symptoms such as a sore throat, runny nose, cough and tiredness, which will pass within a week or two.

Sometimes though, people experience more serious infections that can need hospitalisation and even result in a person dying. People living with CVD are more likely to catch this more serious type of infection.

Vaccines are like a type of ‘practice run’ for your body. They introduce a small, non-infectious part of a bacteria or virus so that your body can build an immune response, which it remembers. This means that it is ready to go with a quicker response if you ever become exposed to that bacteria or virus again.

There are different types of vaccines – some of them contain bacteria or viruses that have been killed or weakened, or just a small piece of them; some have the toxins that are made by bacteria; while others contain instructions that tell your cells to make these small pieces themselves (mRNA vaccines). Vaccines also contain other substances called adjuvants. These help the vaccine be more effective by enhancing the immune response, or reducing the number of doses needed of a vaccine.

Yes, vaccines are safe. In Australia, vaccines are extensively tested to make sure they are safe and work as they are supposed to before being approved for use.

After you have a vaccine, you may feel a bit sick. This can be some pain at the site of the vaccine injection, headache, tiredness or a fever. These side effects are not serious and should clear within a few days. You feel these side effects because your immune system is working hard in response to the vaccine.

There are also rare cases where some people have a more significant side effect to a vaccine. These serious reactions are very uncommon. For example, an allergic reaction only happens in approximately 1 in 1 million people.

Yes, vaccines are safe for people living with CVD. There is no evidence to suggest that vaccines are any less safe for people living with CVD, or that they have any more chance of experiencing side effects. However, there is very clear evidence that people living with CVD are more likely to become very sick from an infection. So the key takeaway for people living with CVD is that the risk of not having a vaccine, and becoming very ill from a respiratory infection, is much greater than your risk of having a side-effect from a vaccine. If you have specific concerns about your health and how vaccines may be for you, you should discuss these with your GP.

Neither the influenza or RSV vaccines increase your risk of heart events such as heart attack or stroke.

In very rare instances some types of COVID-19 vaccine may cause inflammation of the heart (myocarditis of pericarditis). This has been mainly reported in men under the age of 40, with most cases being mild and self-resolving. This risk, though, is much less than the risk of developing a serious heart complication from a COVID-19 infection. For context, it is estimated that your chance of developing heart inflammation is three times greater after a COVID-19 vaccine, but 18 times greater after a COVID-19 infection.

There is a lot of information available online about vaccines and your heart that can be confusing and contradictory. It is always best to look to trusted sources of information when you have questions. These include places like the Department of Health in your state or territory, and large health information services like healthdirect.gov.au. Also, remember that the best place to go for information about your own personal health is your GP.

Antiviral medicines are available that can treat flu infections, but how they impact your risk of CVD is unclear. Results from clinical trials have been contradictory, with some trials showing an improvement in CVD risk, and others showing it worsening, while others show no change. Looking after your heart by keeping active, eating a heart-healthy diet, reducing alcohol intake, and quitting smoking, can all help reduce your risk of developing CVD. Making these heart-healthy lifestyle changes in addition to having a vaccine can give you the best chance of reducing your risk of developing CVD from an infection.

Advice for a respiratory infection is usually to increase the amount of water you consume. But, if you have a heart condition, such as heart failure, having too much fluid can cause strain on your heart. Speak to your GP or healthcare team to work out how much fluid is right for you to have.

These are available over-the-counter at your pharmacy and help ease cold and flu symptoms. Some of them can interfere with heart medicines though, so before you buy any make sure to tell your pharmacist what other medicines you are taking so they can check if they are safe for you.

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