Flu Facts
Commonly called "the flu," influenza is a contagious respiratory illness caused by influenza viruses.
On July 20, 2009, the U.S. Food and Drug Administration (FDA) announced the approval of a vaccine for the prevention of flu during the 2009-2010 influenza season in the United States.
Each year, experts from FDA, the World Health Organization (WHO), the Centers for Disease Control and Prevention (CDC), and other institutions study influenza virus samples and patterns collected from around the world in an effort to identify the strains that may cause the most illness in the upcoming season.
Those forecasts and the recommendations of FDA’s Vaccines and Related Biological Products Advisory Committee enable FDA to determine the three strains that manufacturers should include in their seasonal vaccines for the U.S. population.
Doesn't Protect Against the 2009 (pandemic) H1N1 Influenza Virus
The newly approved influenza vaccine is directed against strains of influenza that were expected to be circulating during the 2009-2010 influenza season, based on information available in February, when a decision regarding the composition of the vaccine was made.
The seasonal flu vaccine will not protect people against the 2009 (pandemic) H1N1 influenza virus, which emerged later in the year and resulted in the declaration of a pandemic by the WHO in June 2009. FDA is working with manufacturers, international partners, and other government agencies to facilitate the availability of a safe and effective vaccine against the 2009 (pandemic) H1N1 influenza virus.
About Seasonal Influenza
- According to CDC, between 5 and 20 percent of the U.S. population develops seasonal influenza each year. More than 200,000 people are hospitalized from its complications and about 36,000 people die.
- Symptoms of the flu include fever, headache, body aches, chills, extreme exhaustion, and weakness.
- Influenza is spread through coughing or sneezing. You can also get it by touching objects carrying the virus, especially when you then touch your mouth or nose. Such objects include telephones and door knobs.
- Most healthy adults may be able to infect others one day before their own symptoms develop and up to five days after becoming sick.
- Washing your hands often is a key strategy for preventing influenza. Teach your kids about the importance of hand washing. Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.
- Most people recover from the flu within one to two weeks. But some develop serious complications such as pneumonia, ear infections, sinus infections, dehydration, and worsening of chronic medical conditions such as congestive heart failure, asthma, or diabetes.
Refer to Flu.gov for more information.
About 2009 H1N1 Influenza
- The spread of the 2009 H1N1 influenza virus is thought to occur the same way that seasonal influenza spreads. The symptoms of the 2009 H1N1 influenza in people include fever, cough, sore throat, runny or stuffy nose, body aches, headache, chills and fatigue. A significant number of people who have been infected with this virus also have reported diarrhea and vomiting.
- Illness with the 2009 H1N1 influenza has ranged from mild to severe. While most people who have been sick have recovered without needing medical treatment, hospitalizations and deaths from infection with this virus have occurred.
- Unlike seasonal influenza, the 2009 H1N1 influenza virus has affected more people younger than 25 years of age rather than older people. At this time, there are few cases and few deaths reported in people older than 64 years old, which is the opposite from what happens with seasonal influenza.
- Pregnancy and other previously recognized high risk medical conditions known to increase the risk of complications from seasonal influenza appear to be associated with increased risk of complications from the 2009 H1N1 influenza virus as well. These underlying conditions include asthma, diabetes, immune system problems, and heart disease.
For more information about the H1N1 Influenza, refer to the Missouri Department of Health and Senior Services website.
About Seasonal Influenza Vaccines
- There are two kinds of influenza vaccines: one type is an injection or shot in the arm and the other type is administered into the nose with a nasal sprayer. The shot contains inactivated (killed) influenza viruses, and the nasal vaccine contains live viruses that are weakened.
- Autumn is the best time to get vaccinated against seasonal influenza, although getting the vaccine in the winter months when influenza season often peaks is also beneficial as outbreaks of influenza often continue through the early spring months.
- Young children, people with chronic medical conditions, and elderly people are at higher risk for seasonal flu-related complications. Vaccination of these groups is critical.
- Influenza immunization of health care personnel is important to help decrease the risk of contracting influenza and spreading infection to others.
- You can't get the flu from the influenza vaccine. Some people do get a mild fever, body aches, and fatigue for a few days after the vaccine, and soreness at the injection site is a common side effect of the shot. The most common side effects seen with administration of the nasal vaccine include runny nose or nasal congestion in recipients of all ages, fever of more than 100 degrees Fahrenheit in children two to six years of age, and sore throat in adults.
This information was taken from the FDA's Consumer Update page, which features the latest on all FDA-regulated products.
Current as of September 3, 2009