Seasonal influenza can cause serious health problems and death, especially for those with underlying health concerns.

The flu is nothing to be sneezed at.  While most people recover without problems, sometimes the flu leads to serious complications, like bacterial pneumonia, bronchitis and dehydration, and worsening of chronic medical conditions, such as congestive heart failure, asthma, or diabetes.  

Influenza is a major cause of illness and death in the United States and leads to as many as 36,000 deaths and 114,000 hospitalizations in an average year. 

People who are at the highest risk for experiencing complications include:

• People who are 65 years old or older (although some medical professionals quote 50 as the target age) even if they're active and in excellent health.  Flu is the fifth leading cause of death among the elderly.
  
  
• People with chronic health problems like diabetes, heart disease, kidney disease, or lung conditions or suffer from weakened immune systems.
  
  
• Women who are pregnant or plan to be during flu season.
  
  
• Children between 6 months and 5 years old, with an emphasis on children under age two.  They are as likely to be hospitalized for flu as people over age 65.
  
  
• Children and teenagers who are on aspirin therapy.
  
  
• People who live in institutions such as nursing homes.

Of course, people who aren't considered to be at high risk can also experience serious complications. 

Don't take chances.  Call a doctor when:

• An infant under age 3 months has a fever of 100.4° F (38° C) or higher.
  
  
• A child age 3 months or older has a fever of 104° F (40° C) or higher that does not come down after 2 hours of home treatment.
  
  
• An adult's fever is high or prolonged or does not being to go down after 5 days. It's common for adults with the flu to have high fevers [up to 103°F (39.4°C)] for 3 to 4 days.  Persistent fever can be a sign of a secondary infection in your body that should be treated.
  
  
• A child or adult has labored, shallow or rapid breathing or chest pain.
  
  
• A child or adult has a fever and a severe headache or stiff neck, seems confused or is hard to wake.
  
  
• Symptoms improve but get worse again, including a fever that goes away and then returns.
  
  
• Someone who has other health problems (lung, heart, or kidney disease or diabetes) or is being treated with chemotherapy comes down with the flu.
  
  
• Someone who has a long-term respiratory illness such as asthma or chronic obstructive pulmonary disease (COPD) comes down with the flu.
  
  
• A child or adult:
• Vomits repeatedly and can't keep fluids down
• Experiences severe pain when swallowing
• Experiences a cough that doesn't go away for more than 2 to 3 weeks