The flu, also called influenza, is an infection of the nose, throat and lungs. It's caused by a virus. The flu is a type of respiratory infection. It spreads easily. That means it's contagious.

If you have heart disease, it's important to take steps to protect yourself against the flu. Complications from the flu are more likely in people with heart disease.

You can reduce your risk of flu and its complications by getting an annual flu vaccine. Although the flu vaccine isn't 100% effective, it's still your best defense against the flu. Health care providers have long recommended the vaccine for older adults and other high-risk groups, including those with heart disease.

If you have heart disease, you're more likely to develop complications from the flu. Complications from the flu include:

• Pneumonia
• Bronchitis
• Lung failure
• Heart attack
• Death

Having the flu also can make heart failure, diabetes, asthma or other conditions worse.

Researchers actively study the benefits and risks of yearly flu vaccines among people with heart disease, including heart failure. Some studies show that getting a yearly flu shot lowers the risk of heart attack, stroke and heart-related death in those with heart disease. But more studies are needed.

Flu shots are safe for most people who have heart disease.

The nasal spray flu vaccine (FluMist) isn't recommended for people with heart disease or who are 65 years and older. Unlike the flu shot, the nasal spray flu vaccine is made with a live virus.

The flu shot is usually given in the upper arm. Some people get temporary side effects. These may include mild soreness at the injection site, muscle aches or a mild fever. You can't get the flu or coronavirus disease 2019 (COVID-19) from a flu vaccine.

Check with your health care provider before getting a flu shot if:

• You have or think you have COVID-19
• You've had a serious allergic reaction to the flu vaccine in the past
• You had Guillain-Barre syndrome develop after getting a flu shot
• You have a fever when you go to get a flu shot

You can still get a flu shot if you're allergic to eggs.

The Centers for Disease Control and Prevention recommends a yearly flu vaccine for everyone age 6 months or older. The agency recommends a high-dose flu vaccine for adults age 65 and older, if available.

It's best to get a flu vaccine in September or October. However, if flu shots aren't yet available or you haven't had one yet, you can still get a flu shot until January or sometimes later.

It's more important than ever to get a flu vaccine. Both the flu and COVID-19 — another respiratory infection — may be spreading at the same time. The two infections can cause similar symptoms. A flu shot could reduce symptoms that might be confused with those caused by COVID-19. However, the flu vaccine does not prevent COVID-19.

If you live with or care for someone who has heart disease, you should get a yearly flu vaccine too. Getting one helps lower the risk of infection for you and those around you.

You don't have to get your flu shot from your cardiologist. The flu shot is available at primary care provider offices, public health departments and some pharmacies. Call first to determine if the flu vaccine is available and if you need an appointment.