Don't Fear the Needle: The Flu Shot is for Everyone
Go ahead, get shot. In fact, it's recommended. That's the advice of the U.S. government, anyway, who recommends that every man, woman and child be immunized against the flu.
I Feel Awful, But What Exactly Is It?
It strikes just about every household every year, leading flu to be one of the most commonly known illnesses. It is also widely misunderstood.
Influenza, commonly known as the flu, is a highly contagious, seasonal, respiratory infection and is caused by influenza type A and type B viruses. Its primary season is winter, and for those folks in North America, the Centers for Disease Control and Prevention reports that the greatest number of cases typically occur during January and February.
What happens when flu viruses first attack is the tissues lining the throat, nose and lungs get infected, and in as quickly as a day the symptoms can appear, though it may take as long as four days.
Then, the all-too-familiar signs of fever, chills, headache, body aches, tiredness, dry cough, sore throat and nasal stuffiness settle in. Although most people recover from the flu within a few days to two weeks, potentially life-threatening pneumonia and other complications can develop without warning.
Complications from flu send more than 200,000 people in the United States to the hospital each year, according to the CDC, and the 2009-10 flu season created a global public health concern.
Last season's strain, type A H1N1 influenza, caused the first global flu pandemic since 1968.
While death rates from flu complications vary each season, depending on the circulating virus strains, it is estimated that between 8,900 and 18,300 people died in the United States during the 2009-10 flu season.
Flu Vaccine Options
The two options for influenza immunization include: flu shot or nasal vaccine. Both vaccines induce immunity to the flu within about two weeks, but have some important differences.
The 2010-11 seasonal flu shot, or inactivated influenza vaccine, contains three strains of inactivated flu viruses: type A H1N1, type A H3N2 and type B. The flu shot has been approved by the U.S. Food and Drug Administration (FDA) for anyone 6 months and older.
The 2010-11 seasonal flu nasal spray, also known as the live, attenuated influenza vaccine, contains weakened strains of the same three viruses that are in the traditional flu shot. Although the influenza viruses in the nasal spray remain alive, they do not cause the flu.
The flu nasal vaccine is an FDA-approved option for healthy children as young as 2 to adults age 49. Pregnant women and people with chronic health problems should not take the flu nasal spray, but are encouraged to get a flu shot.
People with an allergy to eggs and those who have had a severe reaction to a prior flu vaccine should talk with their doctor before receiving an influenza immunization.
A New Flu Immunization Strategy
In the wake of the 2009 H1N1 flu pandemic, the U.S. Department of Health and Human Services reworked its policy for the 2010-11 flu season and targeted essentially everyone in the U.S. Through near universal immunization, the new public health policy reflects a strategic shift to broaden the recommendation to more than just high-risk groups.
In February 2010, the CDC's Advisory Committee on Immunization Practices (ACIP) issued new recommendations, advocating influenza vaccination for all people six months and older in the U.S. Previous ACIP recommendations largely aimed for citizens at greatest risk for flu complications and those who could potentially transmit the infection to high-risk people.
This new strategy includes healthy adults 19 to 49, a group that was previously evaluated on a case-by-case basis.
"We currently have three strains of influenza circulating in the population: H1N1, H3N2 and influenza type B," CDC spokesman Joe Dimond said. "When H3N2 last circulated during the 1992-93 flu season, it was particularly hard on the elderly population. The H1N1 virus tends to hit the younger population; 90 percent of H1N1 flu fatalities in the 2009-10 season occurred in people younger than age 65."
Flu vaccines are not new and have been used to prevent infections since the 1940s. With a targeted flu immunization strategy, influenza has continued to infect about five percent to 20 percent of the population each season, the CDC says.
The emergence of the pandemic H1N1 flu strain raised the stakes in the public health war on influenza. With the shift to universal flu immunization, the CDC hopes to achieve a greater level of prevention against influenza throughout the entire population than in previous years.
"Right now, we have a flu threat that covers all age groups," Dimond said.
How the Flu Spreads and How the Vaccine Works
Basically, a flu vaccine primes the immune system to fight off seasonal influenza viruses.
Proteins in the vaccine stimulate the production of flu-specific antibodies. When an immunized person is exposed to influenza viruses, preformed flu-specific antibodies kill the germs, preventing flu and slowing the spread of the illness among the larger population.
Flu viruses are also tough to contain because they are highly contagious and can spread easily from one person to another.
When someone with the flu coughs, sneezes or talks, countless infectious flu particles enter the air. These particles are powerful enough to infect another person 6 feet away, according to the CDC. Touching a surface contaminated with flu viruses and then touching the face can also lead to infection.
The kicker is, people infected with the flu are contagious before they might feel sick themselves. During the 24 hours before developing symptoms, people infected with the flu can spread the virus to others. This symptomless but contagious period of flu helps spread the virus among those without flu immunity throughout the flu season.
Are You Part of the Herd?
The vulnerability of a community to the flu depends on how many people are susceptible to the infection, a concept known as herd immunity.
When a large proportion of people within a community are immunized against the flu, chances drop dramatically that unimmunized members will catch the disease. The CDC hopes to strengthen the entire population's resistance to the flu through universal immunization.
"Flu is easily transmissible and can be a deadly disease," said Dr. Deborah Wexler, executive director of the Immunization Action Coalition. "By getting vaccinated, you're not only protecting yourself, you're protecting the people you care about -- your children, parents, grandparents, friends and community."
The concern is that forgoing a flu shot will simply perpetuate the illness and facilitate an epidemic.
"You may get the flu and have only mild symptoms," Wexler said. "But the next person you transmit the virus to may become seriously ill."
So, go ahead, get that flu shot. The life you save may be that of someone you don't even know.