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Healthy Tips

Flu: Who Is Most at Risk?

Conditions That Can Put You at Higher Risk for Complications

During flu season, you may see stories about seemingly healthy people who lost their life to influenza, or “flu.” While it is rare for otherwise-healthy people to die from flu, certain conditions can put you at higher risk for suffering severe complications from the illness.

How Flu Affects Elderly People

Flu results in approximately 40,000 deaths in the U.S. each year, nearly all of which are in the older adult population, according to Theresa Rowe, DO, geriatric specialist at Northwestern Memorial Hospital. The Centers for Disease Control and Prevention (CDC) reports that people ages 65 and older account for between 71 percent and 85 percent of flu-related deaths and 54 percent to 70 percent of flu-related hospitalizations in the U.S.

Dr. Rowe explains some reasons that elderly people are particularly affected by flu:

  • The immune system becomes weaker with age, which makes older adults more likely to become infected, and they are more likely to have a prolonged and severe illness as a result.
  • Older adults are more likely to have chronic conditions like chronic obstructive pulmonary disease (COPD), which increase their susceptibility to infections such as flu.
  • Flu can be more difficult to diagnose in older adults, as classic symptoms such as fever, cough and general aches are often not present in this population.

Because of their weaker immune systems, Dr. Rowe recommends adults 65 and older get an annual flu vaccine specially formulated for people in their age group. She says adults should get vaccinated early in the fall if possible, but those who miss that window should still get vaccinated any time during flu season. During flu outbreaks in long-term care facilities, which can be particularly devastating, antiviral medications may be used for prevention of influenza.

How Flu Affects Babies and Young Children

In children birth to 5 years old, influenza is more likely to cause severe illness and a bacterial co-infection. Lubna S. Madani, MD, medical director of Northwestern Medicine Immediate Care, says children in this age group are at higher risk of flu complications because:

  • Their anatomy does not allow congestion to drain as well, and children can have fluid in the ear that eventually can grow bacteria.
  • Young children, especially those who are frequently around other children, such as in a daycare setting, can carry bacteria in their noses. This bacteria may not pose a threat when the child is healthy, but if a virus such as flu infects the child, that bacteria can cause a secondary bacterial co-infection that can be severe and possibly fatal.

“Because the virus is spread through droplets, children may be more prone to spreading the flu because they are more prone to touching their noses, and poor hand-washing,” says Dr. Madani.

Therefore, Dr. Madani suggests giving them an immunization and teaching children to:

  • Cover their mouth and nose while coughing or sneezing, and make sure they throw away dirty tissues immediately.
  • Sneeze or cough into the sleeve of their clothing at the inner elbow to contain sprays of saliva and secretions and to avoid contaminating their hands.
  • Wash their hands often with soap and water, especially after their cough or sneeze.
  • Avoid touching their eyes, nose or mouth, as germs are often spread this way.

How Flu Affects Pregnant Women

People who are pregnant or who have recently given birth experience changes in the immune system, heart and lungs. Therefore, according to the CDC, they are more likely than people who are not pregnant to have severe illness from flu. Deborah S. Clements, MD, family medicine physician at Northwestern Medicine Grayslake Outpatient Center in Grayslake, Illinois, says that those who are pregnant and who get flu may develop dehydration or high fever, which puts their unborn babies at risk. Unborn babies may be more likely to experience neural tube defects or other adverse conditions if they are exposed to fever in the womb.

How Flu Affects People With Cancer or Other Serious Illnesses

People with chronic disease or who have weakened immune systems are also at higher risk for contracting and developing serious illness from flu, says Dr. Clements. Among those who may be at higher risk for complications from flu:

  • People who have cancer or a history of cancer due to a weakened immune system
  • People with autoimmune disorders due to immune system dysfunction
  • People with asthma due to the risk of triggering asthma attacks
  • People with a history of heart disease or stroke, because flu can lead to inflammation in the body that could trigger a worsening of existing conditions
  • People with diabetes, because it can affect the ability to control blood sugar
  • People who have cancer or a history of cancer, and those with autoimmune disorders, due to a weakened immune system
  • People with asthma, because of the risk of triggering asthma attacks
  • People with a history of heart disease or stroke, because flu can lead to inflammation in the body that could trigger a worsening of existing conditions
  • People with diabetes, because it can affect the ability to control blood sugar

If You Get Sick

Dr. Clements says flu should be suspected if you develop a fever over 101 degrees F accompanied by muscle aches and/or fatigue. If you think you have flu, Dr. Clements advises:

  • Seek medical care early. Antiviral medication may help shorten the length of the illness and decrease its severity, but the medication needs to be administered early in the illness to be most effective.
  • While antibiotics can’t cure flu, it is also possible for influenza to lead to other types of infection or conditions caused by bacteria that could be treated with an antibiotic.
  • Stay home. Your body needs rest, and staying away from other people will help prevent the illness from spreading and possibly infecting someone who is particularly vulnerable.

How to Avoid Flu

Of course, as the saying goes, an ounce of prevention is worth a pound of cure.