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To learn how best to protect yourself and your family from the flu, click below for answers to these frequently asked questions.

What causes the flu?
The flu is a contagious respiratory illness caused by influenza viruses which constantly change resulting in new strains each year. Symptoms include fever (usually high), headache, extreme tiredness, dry cough, sore throat, runny or stuffy nose and muscle aches. The flu can result in illness ranging from mild to life-threatening. An estimated 10 percent to 20 percent of Americans get the flu each year, with an average of 114,000 hospitalized for flu-related complications. Some 36,000 Americans die each year from complications.

How does the vaccine work?

The flu vaccine is an inactivated viral vaccine. Each year the influenza viruses predicted to be predominant during the flu season are grown in chicken eggs, harvested, and then killed through chemical means. They are then purified and tested for safety before being used to create a vaccine. When given to humans, the vaccine stimulates the production of antibodies that fight off the viruses included in the vaccine. It takes about two weeks after vaccination to develop antibodies against the flu.

The effectiveness of the flu vaccine varies from year to year depending on the degree of similarity between the virus strains included in the vaccine and those actually circulating during the flu season. The vaccine can prevent symptoms of flu infection in up to 90 percent of healthy young adults, but its effectiveness can be as low as 30 percent among very elderly, frail persons.

In the United States, the flu season strikes during November through April, with peak activity usually taking place between late December and early March. The best time to get vaccinated is between September and mid-November.

Why is there a shortage of vaccine?
The current vaccine shortage began Oct. 5 when British regulators shut down flu shot manufacturer Chiron Corp.’s factory in Liverpool, England, reducing the expected U.S. supply by 48 million doses, or nearly half. The plant was closed because of contamination, and the U.S. Food and Drug Administration later confirmed that Chiron’s doses were not safe to use. The U.S. government had been relying on only two flu shot manufacturers for the nation’s supply: Chiron and Aventis Pasteur. Aventis, which had planned to provide the U.S. with about 55 million doses, has since promised to boost its production and provide an additional 2.6 million shots by January.

Who should be vaccinated this year?
Due to the current shortage of vaccine, only people who are at greatest risk from the flu and related complications should receive a shot. Everyone in the following categories should be vaccinated:

  • People 65 years of age or older
  • Children ages 6 months to 23 months (children under the age of 6 months cannot be vaccinated)
  • Adults and children 2 years of age and older with chronic lung or heart disorders, including heart disease and asthma
  • Women who will be pregnant during the flu season
  • Adults and children 2 years of age and older with chronic metabolic diseases (such as diabetes), kidney diseases, blood disorders (such as sickle cell anemia), or immune disorders (such as HIV/AIDS)
  • Children and teens, 6 months to 18 years of age, who take aspirin daily
  • Residents of nursing homes and other chronic-care facilities
  • Household members and out-of-home caregivers of infants under the age of 6 months
  • Health-care workers who provide direct, hands-on care to patients

MOWBRAY, COLEMAN
J. R. Hernandez  /  AP file
Louise Mowbray, 90, is given a flu shot by Barry O. Coleman at the Coleman Pharmacy in El Paso, Texas, Monday, Oct. 18, 2004.
In order to protect those at greatest risk, healthy people aged 2 to 64 should skip getting a flu shot this year. FluMist, a nasal-spray flu vaccine, is an option for healthy people ages 5 to 49. It cannot be given to pregnant women and is not recommended for health-care workers taking care of patients with compromised immune systems.

People who have had previous vaccine-associated allergic reactions should not get the flu vaccine in any form. Also, people with egg allergies should avoid immunization because the viruses used in the vaccine are grown in chicken eggs.

How can you find a flu shot?
If you are in a high-risk category and your regular doctor or clinic has no vaccine, call your local health department. Explain your situation and ask about other options. Health departments are trying to make sure that as many high-risk people will eventually be able to receive the vaccine. In the meantime, many Americans are traveling to Canada to receive shots. Also, the American Lung Association is posting the names of some public clinics across the United States with available vaccine at www.lungusa.org.

How can you prevent the spread of flu?
The flu spreads easily from person to person and can overtake an area quickly. It is transmitted primarily through respiratory droplets found in coughs and sneezes, which can travel up to 3 feet and still infect someone. Studies show infected people can spread the virus before developing symptoms and up to 7 days after symptoms appear.

While the flu can be hard to avoid, there are certain things you can do to prevent its spread:

  • Avoid close contact with sick people.  If you have the flu, keep your distance from others to prevent infecting them.
  • Don’t cough or sneeze into your hand. Cover your nose and mouth with a tissue when you cough or sneeze, and immediately throw away the tissue afterward. If you don’t have a tissue handy, cough into your sleeve.
  • Wash your hands frequently with soap and warm water or an alcohol-based hand cleaner. Be sure to scrub them for 15 to 20 seconds, or about the time it takes to sing the “Happy Birthday” song twice.
  • If you become sick with the flu, stay home from work or school in order to prevent others from catching the illness.

Sources: Centers for Disease Control and Prevention; Associated Press

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