For most people, the flu is a mild illness – albeit an unpleasant one: Fever, chills, congestion, sore throat muscle aches, fatigue and generally feeling lousy. But most people will not need medical care and will recover in less than two weeks. However, for elderly people, the flu can cause serious complications, like pneumonia and bronchitis that land them in the hospital, or in some cases, cause death. In fact, adults older than age 65 account for 90 percent of flu-related deaths and 60 percent of flu-related hospitalizations, according to the Center for Disease Control and Prevention (CDC).

"Elderly people who have chronic health conditions are particularly at risk for several reasons. First, the immune system weakens with age, leaving older adults more vulnerable to severe disease when they get sick. Secondly, chronic health conditions can exacerbate the flu, making it worse, which leads to serious complications," says Tom Skinner, senior press officer for the CDC. Likewise, the flu can make chronic health problems worse.

The CDC says these medical conditions cause elders to be at higher risk for flu-related complications:

  • Diabetes: People with diabetes are at high risk of severe disease and complications of influenza. The virus may also interfere with glucose management putting people with type 1 diabetes at an increased risk of diabetic coma.
  • Asthma, chronic lung disease and COPD: People with chronic respiratory conditions are more susceptible to flu complications, because any respiratory infection, including the flu, can affect the lungs, causing inflammation and airway narrowing.
  • Heart disease: Any heart condition, including congenital heart disease, congestive heart failure and coronary artery disease increases flu complications. Flu can lead to a heart attack. In fact up to half of unexpected influenza deaths are due to heart disease.
  • Kidney disorders: Kidney disease can weaken a body's ability to fight off the flu and it can also make kidney disease worse. If fact, for people who have had a kidney transplant, the flu could cause the body to reject the new kidney.
  • Liver disorders: Similar to kidney disease, the flu can make liver disease worse. Flu can also cause the body to reject the new liver.
  • Neurological conditions: Health problems like epilepsy, Parkinson's disease, history of strokes seizures and Huntington's disease can weaken the body's ability to fight off the flu.
  • Cancer and HIV: In any disease that causes a weakened immune system, the flu can further compromise the immune system, thus increasing the risk of developing serious flu-related complications.

Get medical care right away if your loved one:

  • Has difficulty breathing or chest pain
  • Has purple or blue discoloration of the lips
  • Is vomiting and unable to keep liquids down
  • Shows signs of dehydration, such as feeling dizzy when standing, being unable to urinate, or (in infants) crying without shedding tears
  • Has seizures (for example, uncontrolled convulsions)
  • Is less responsive than normal or becomes confused

To reduce the risk of an elder contracting the flu and suffering serious complications, the National Council on Aging (NCOA) recommends elders get a flu vaccine every year. "Prevention is critically important. Unfortunately, vaccination rates are alarmingly low among older adults. Nearly 30 percent went unvaccinated during the 2011-2012 flu season," says Richard Birkel, PhD and senior vice president of NCOA, which has implemented the Flu + You program to "ensure that elders and those who care for them fully understand the importance of annual immunization and the vaccine options available to them."

The flu vaccine is updated each year based on data from a worldwide virus tracking system that helps public health officials predict which virus strains will circulate during the season.

People age 65+ have two vaccine options: the traditional flu shot, and a higher dose flu shot designed specifically to address the age-related decline of the immune system. The higher dose vaccine triggers the body to produce more antibodies against the flu virus than would be produced by the traditional flu shot. Both vaccine options are covered by Medicare Part B with no copay.