The flu (influenza) is a seasonal virus that causes mild to severe symptoms. Some people recover in about a week, while others can be at risk of serious, life threatening complications.

The risk of complications increases if you’re over the age of 65. Older adults tend to have a weaker immune system, which naturally occurs as we age. And when your immune system isn’t strong, it becomes harder for the body to fight off a virus.

When a flu infection worsens, it can progress to pneumonia and lead to hospitalization, and sometimes death.

If you’re over the age of 65, here’s what you need to know about the flu, including symptoms, complications, and prevention.

The onset of flu symptoms can happen quickly, with some people developing symptoms 1 to 4 days after exposure to the virus.

If you become sick, it’s important that you know how to differentiate flu symptoms from common cold symptoms. Flu and cold symptoms can be similar, but cold symptoms are usually milder. In addition, cold symptoms come on gradually.

It’s different with the flu. Not only is the onset of symptoms abrupt, but the flu also causes symptoms that might not occur with the common cold.

Symptoms of the flu and common cold include:

  • runny nose
  • congestion
  • sore throat
  • coughing

If you have the flu, additional symptoms may include:

  • fever
  • body aches
  • chills
  • fatigue
  • weakness
  • chest discomfort
  • headache

If you’re over the age of 65 and develop any of these flu symptoms, see a doctor right away to reduce the risk of complications.

If you see a doctor within the first 48 hours of your first symptom, your doctor may prescribe an antiviral medication. When taken early, this medication can reduce the duration and severity of your illness.

Flu complications aren’t as common in younger people and those with a healthy immune system. But up to about 85 percent of seasonal flu-related deaths occur in people who are 65 years or older.

Additionally, up to about 70 percent of flu-related hospitalizations occur in the same age group.

Some flu-related complications aren’t as severe and may include a sinus or an ear infection. More serious complications can include bronchitis and pneumonia, which affect the lungs.

Bronchitis occurs when inflammation develops in the lining of the bronchial tubes. These are the tubes that carry air to the lungs. Symptoms of bronchitis can include:

  • coughing up yellow, gray, or green mucus
  • fatigue
  • shortness of breath
  • fever
  • chest pains

Bronchitis can lead to pneumonia, an infection that causes inflammation in the air sacs in one or both lungs. Pneumonia can cause chest pains, shortness of breath, and a severe cough.

In older adults, pneumonia can also cause a lower than normal body temperature, confusion, and nausea and vomiting.

Pneumonia is a serious complication. If left untreated, bacteria can get into the bloodstream and cause organ failure. This lung infection can lead to fluid accumulation in the lungs or a lung abscess.

Other complications that may occur with the flu include inflammation of the heart, brain, and muscles. It can also lead to multi-organ failure. If you live with asthma or heart disease, the flu virus can worsen these chronic conditions.

Don’t ignore severe symptoms that develop while battling the flu. See a doctor immediately if you have shortness of breath, chest pain, dizziness, vomiting, or mental confusion.

If you don’t see a doctor within the first 48 hours of symptoms, antiviral treatment for the flu is less likely to shorten the duration or reduce the symptoms of the infection. However, antiviral treatment may still be given if you have a high risk of complications.

There’s no cure for the flu, so the virus must run its course. Symptoms do respond to over-the-counter cold and flu medications, though. You can take ibuprofen (Advil, Motrin) as directed for pain and a fever.

It’s important to get plenty of rest to strengthen your immune system and fight the virus. By taking care of yourself at home, you should feel better within 1 to 2 weeks.

If you experience complications, your doctor may have to prescribe an antibiotic. This will treat a secondary infection, such as an ear infection, sinus infection, bronchitis, or pneumonia. You may also need a prescription cough suppressant for a severe cough.

Prevention is key to avoid the flu and its complications. Everyone should consider getting an annual flu vaccination, especially if you are age 65 and older.

If you fall in this age group, your doctor can give you a vaccination that’s recommended for all age groups, or a vaccination that’s designed specifically for people age 65 and older.

This includes the high-dose flu vaccine Fluzone, which builds a stronger immune system response following the vaccination.

Another option is the Fluad vaccine, which is also designed to build a stronger immune system response to vaccination.

The flu vaccine isn’t 100 percent effective. But it can reduce the risk of the flu by 40 to 60 percent.

Flu season is between October and May in the United States, so you should get a flu shot before the end of October. Remember, it takes about two weeks for the flu shot to be effective.

In addition to an annual vaccination, there are other ways to protect yourself against the flu:

  • Avoid crowded areas.
  • Wear a face mask and steer clear of sick people while in public.
  • Wash your hands regularly with warm soapy water, or use antibacterial gel throughout the day.
  • Don’t touch your face, mouth, or nose with your hands.
  • Boost your immune system by eating a healthy diet, exercising regularly, and reducing stress.
  • Regularly disinfect surfaces in your home (light switches, door knobs, telephones, toys).
  • Visit a doctor if you develop flu symptoms.

Everyone should take steps to protect themselves against the flu. Prevention is especially important if you’re 65 or older due to the risk of flu-related complications.

Take steps to protect yourself and notify your doctor immediately if you develop any flu symptoms.