QUESTION: What exactly is the flu?
DR. HASSOUN: The flu is a contagious respiratory illness caused by influenza viruses that affects the nose, throat, air passages and lungs. It can cause mild to severe illness and, at times, can lead to death. People who have the flu often feel some or all of these symptoms: fever, cough, sore throat, runny or stuffy nose, body aches, headaches and fatigue. Some people may experience vomiting and diarrhea, but this is more common in children.
QUESTION: How dangerous is the flu?
DR. HASSOUN: On average, in the U.S., there are 36,000 deaths and 200,000 hospitalizations every year due to influenza and its related complications. Each flu season a range of 5 percent to 20 percent of the general population comes down with the flu. Nursing home attack rates can be up to 60 percent. More than 85 percent of influenza deaths occur in people over age 65.
During 2009-2010, a new flu virus spread worldwide causing the first flu pandemic in more than 40 years. It is estimated that the 2009 H1N1 pandemic resulted in more than 12,000 flu-related deaths in the U.S. In contrast to seasonal flu, nearly 90 percent of the deaths occurred among people younger than 65 years of age
QUESTION: How does someone "catch" the flu?
DR. HASSOUN: The flu is spread easily from person-to-person, and most experts believe that flu viruses spread mainly by droplets expelled by coughing, sneezing or talking. These particles generally settle out of the air within 3 feet to 6 feet from their origin. Flu occurs more often in the winter months because people spend more time in close contact with one another. Healthy adults may be able to infect others beginning one day before symptoms develop and up to five to seven days after becoming sick. Children may pass the virus for longer than seven days.
QUESTION: What are some complications of flu and who is most at risk?
DR. HASSOUN: Most people who get influenza will recover in a few days to less than 2 weeks, but some people will develop complications like pneumonia, bronchitis, sinus and ear infections, asthma or COPD exacerbation. People with chronic congestive heart failure may have worsening of this condition that is triggered by the flu. Risk factors for influenza complications include: chronic lung disease (asthma or chronic obstructive pulmonary disease), immunosuppressive conditions, cardiac disease, pregnancy, diabetes, obesity, being younger than 5 or older than 65, and chronic medical conditions.
QUESTION: How is flu diagnosed?
DR. HASSOUN: Influenza is usually diagnosed based on symptoms (fever, cough and muscle aches). Lab testing for influenza is performed in certain cases, such as during a new influenza outbreak in a community.
QUESTION: Can it be treated?
DR. HASSOUN: Treating the symptoms of influenza with rest, fluids and over-the-counter medications can help you feel better but will not make the flu go away faster. On the other hand, antiviral medicines such as Tamiflu or Relenza can be used to treat influenza and may reduce the severity and duration of symptoms by about one day. Not every person with influenza needs an antiviral medicine; the decision is based upon your risk of developing complications. These medicines are most effective for seasonal influenza when taken within the first 48 hours of flu symptoms.
Antibiotics are NOT useful for treating viral illnesses such as influenza and should only used if there is a bacterial complication of the flu. Antibiotics can cause side effects and lead to development of antibiotic resistance.
There are a wide variety of herbal, homeopathic, and other complementary and alternative treatments that are marketed for influenza. Unfortunately, there have been few well-designed studies to evaluate their efficacy and safety.
QUESTION: Is there anything we can do to keep from getting the flu in the first place?
DR. HASSOUN: The single best way to prevent seasonal flu is to get vaccinated each year, but good health habits -- like covering your cough or sneeze, washing your hands, avoiding close contact with people who are sick -- can help. Avoid touching your eyes, nose or mouth. Get plenty of sleep, be physically active, manage your stress, drink plenty of fluids and eat nutritious food.
QUESTION: What about the vaccine?
DR. HASSOUN: The seasonal flu vaccine is made from the likely predominant influenza viruses during the season. About two to four weeks after vaccination, antibodies develop that protect against influenza virus infection. Flu vaccines will not protect against flu-like illnesses caused by non-influenza viruses.
QUESTION: When is the best time to get vaccinated?
DR. HASSOUN: Yearly flu vaccination should begin in September -- or as soon as the vaccine is available -- and continue throughout the flu season, which can last as late as May. This is because the timing and duration of flu seasons vary.
QUESTION: Who should get vaccinated?
DR. HASSOUN: Everyone 6 months and older should get a flu vaccine each year. It's especially important for anyone at high risk of having serious flu-related complications and for anyone that lives with or cares for people at high risk for developing flu-related complications.
QUESTION: Can the flu shot make you sick?
DR. HASSOUN: A flu shot cannot cause flu illness. The influenza viruses contained in a flu shot are inactivated (killed), which means they cannot cause infection. Flu vaccine manufacturers kill the viruses in the process of making the vaccines, and batches of flu vaccine are tested to make sure they are safe.