Vaccines Stand Ready for Flu Season Vaccines Stand Ready for Flu Season
U.S. Food and Drug Administration

Commonly called "the flu," influenza is a virus-induced, contagious respiratory illness. The Food and Drug Administration (FDA) plays a key role in protecting Americans against seasonal strains of flu.

Assuring the safety of influenza vaccine is one of the agency’s top priorities. So is ensuring that there’s enough vaccine for everyone who wants it—especially for people who are at risk of complications of influenza.

There are two kinds of influenza vaccines:

The flu shot contains inactivated, or killed, influenza viruses. The nasal vaccine is known by the trade name of FluMist. It contains weakened, live viruses, and is sprayed into both nostrils.

Autumn is the best time to get vaccinated, although getting the vaccine in the winter months when flu season often peaks is also recommended.

Six for This Season

FDA has approved six vaccines for the 2008-2009 flu season. All are for use against influenza disease caused by influenza virus types A and B. They are

Afluria, for adults 18 years of age and older Fluarix, for adults 18 years of age and older FluLaval, for adults 18 years of age and older Fluvirin, for people 4 years of age and older Fluzone, for people 6 months of age and older FluMist, for people ages 2 to 49

Manufacturers of the six vaccines project about 146 million doses will be available for this influenza season, according to the U.S. Centers for Disease Control and Prevention (CDC).

A Challenging Process

"One of the biggest challenges in the fight against influenza is producing new vaccines every year," says Jesse L. Goodman, M.D., M.P.H., Director of FDA’s Center for Biologics Evaluation and Research. "There is no other instance where new vaccines must be made every year. The approval of flu vaccines is a part of FDA’s mission to promote the health of Americans throughout the year."

Experts from FDA, CDC, the World Health Organization, and other institutions annually study virus samples and disease patterns collected worldwide in an effort to identify strains that may cause the most illness in the upcoming season.

Based on those forecasts and on the recommendations of its Advisory Committee, FDA each February decides on the three strains that manufacturers should include in their vaccines for the U.S. population. Each season’s vaccines are modified to reflect the virus strains most likely to be circulating and cause the flu.

In an unusual occurrence, FDA changed all three strains for this year’s influenza vaccine. Usually, only one or two strains are updated from year to year.

This year’s vaccines include the following strains:

an A/Brisbane/59/2007 (H1N1)-like virus an A/Brisbane/10/2007 (H3N2)-like virus a B/Florida/4/2006-like virus Health Professionals Need It Too

The approach of flu season also serves to remind health care workers to get vaccinated against influenza. The U.S. Department of Health and Human Services (HHS) recently launched an initiative to help improve vaccination rates among health care personnel.

Influenza vaccination should be considered a part of patient safety. Studies have shown that only about 4 in 10 health care professionals are vaccinated every year. Those that don’t get vaccinated can cause influenza outbreaks in health care settings.

Flu Facts

What are the symptoms? Seasonal influenza—or flu—is a contagious respiratory illness caused by viruses. Symptoms include fever, headache, body aches, chills, extreme exhaustion, and weakness.

How is it spread? Flu is spread through coughing or sneezing. You can also get it by touching objects that are carrying the virus, such as telephones and door knobs, and then touching your mouth or nose. Wash your hands often and teach children to do the same. Most healthy adults may be able to infect others one day before their own symptoms develop and up to five days after becoming sick.

How many people are affected? Each year, according to CDC, an average of 5% to 20% of the U.S. population gets the flu. More than 200,000 people are hospitalized from flu complications. There are about 36,000 flu-related deaths each year.

What are the possible complications? 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.

Who is at higher risk for complications? Some individuals—particularly elderly people, young children, and people with chronic medical conditions—are at higher risk for flu-related complications. Vaccination of these groups and of health care personnel is critical.

Can you get the flu from a flu shot? Although some people get a mild fever, body aches, and fatigue for a few days, you can’t get the flu from a flu shot. Soreness at the injection site is a common side effect of the flu shot

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