Each year, millions of people suffer from seasonal influenza, which is often called the flu. Flu is a respiratory illness caused by viruses that infect the nose, throat, and sometimes the lungs.
Flu is a mild illness for some people. But for others, including older adults and those with chronic (long-lasting) health conditions, the flu can be very serious and even life-threatening. Getting a flu vaccine every year can help prevent the flu. The vaccine is safe, effective, and available for little to no cost to you.
Most people who get the flu feel better after a few days to two weeks. However, the flu can make you seriously ill. Some people develop other health issues, called complications, because of the flu. Complications can be mild, such as a sinus or ear infection, or more serious, like pneumonia.
Anyone can get sick from the flu, but some people are more likely to have complications. You are more at risk for flu and its complications if you:
Are age 65 or older
Have certain medical conditions such as asthma, diabetes, or chronic kidney disease
Have heart disease or have had a stroke
Live in a nursing home or other long-term care facility
Pregnant people and children younger than five years old are also more likely to get very sick from the flu. Flu vaccination is especially important for people in these higher-risk groups. Learn more about people at increased risk for flu and its complications.
The flu is more dangerous for older adults for a few reasons. One reason is that the immune system — which helps your body fight infections — weakens as you age. For example, because your body is busy fighting off the flu, you might pick up a secondary infection such as pneumonia. A second reason is that older adults are also more likely to have other health conditions, like diabetes, that increase their risk for complications from the flu.
The good news is the flu vaccine reduces your risk of getting the flu and of getting seriously ill if you do get sick with the flu. Flu vaccination is especially helpful for people with chronic health conditions. For example, it has been linked to lower rates of heart problems (cardiac events) among people with heart disease and fewer hospitalizations among people who have chronic lung disease or diabetes. Learn more about the benefits of flu vaccination.
The flu is contagious, which means it spreads from person to person. It mostly spreads through droplets in the air when people with flu cough, sneeze, or talk. It can spread from up to six feet away. Although it isn’t as common, the flu can also spread from surfaces — for example, if you touch something the virus is on and then touch your nose, mouth, or eyes.
It’s possible to spread the flu before you feel sick and when you have symptoms. Typically, people with the flu can spread it a day before, and up to a week after feeling sick. Young children and people with weakened immune systems may be able to spread the flu for even longer. If you or someone you know is sick with the flu, take steps to help prevent spreading the disease
People with the flu can have fever, chills, dry cough, general aches and pains, and a headache. They feel very tired. Sore throat, sneezing, stuffy nose, or stomach problems are less common. What some people call “stomach flu” is not influenza.
