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Flu: Who Is Most at Risk?

Flu Who is Most at Risk

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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 CDC reports that people ages 65 and older account for between 71 and 85 percent of flu-related deaths and 54 to 70 percent of flu-related hospitalizations.

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, says Jill Kelly, MD, a pediatrician at Northwestern Medicine Regional Medical Group in St. Charles, Illinois. “The two most common complications of the influenza virus in children this age are a middle ear infection and pneumonia,” she explains. “They are also more at risk for other respiratory complications like croup, exacerbating a chronic underlying condition like asthma or reactive airway disease.”

Dr. Kelly 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.

• Younger children, especially children under 3 years of age, are more likely to have bacteria go through their bloodstream. That can cause spread of the bacteria to different parts of the body and may cause a serious, life-threatening condition.

• 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.

How flu affects pregnant women

According to the Centers for Disease Control and Prevention (CDC), because women who are pregnant or who have recently given birth experience changes in the immune system, heart, and lungs, they are more likely than women who are not pregnant to suffer severe illness from flu. Deborah S. Clements, MD, family medicine specialist at Northwestern Medicine Grayslake Outpatient Center in Grayslake, Illinois, says that mothers who get flu may develop dehydration or high fever, which puts their unborn babies at risk. Developing babies may be more likely to experience neural tube defects or other adverse conditions if their mother had a fever during pregnancy.

How flu affects people with cancer or other serious illnesses

People with chronic disease or who have weakened immune symptoms are also at higher risk for contracting the flu virus and at higher risk for serious illness caused by 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, 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 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. Read our four quick tips for avoiding flu.

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