The Flu
Ocotber 11, 2006
The flu is a respiratory infection caused by the influenza virus. Its spread from one person to another through contact with contaminated respiratory droplets (i.e., primarily a cough or sneeze). Once the infection has been acquired, it takes one to four days until symptoms begin to show. Patients may experience fever, muscle aches, sore throat, cough, extreme fatigue, headache and runny or stuffy nose. Children may also develop ear pain, nausea and vomiting.
In most patients, flu symptoms resolve in about three to seven days. But tiredness and cough can last for two weeks or longer. In some cases, flu symptoms can become severe or lead to secondary infections or exacerbation of underlying medical conditions (like asthma). The risk for complications is higher among very young children, adults 65 and older, and people with underlying chronic health problems.
According to the Centers for Disease Control and Prevention, about 5 to 20 percent of Americans get the flu every year. The infection causes about 200,000 hospitalizations and 36,000 deaths annually.
Preventing the Flu: The Flu Shot
One of the best ways to reduce the risk of getting the flu is with a flu shot. The flu shot is an injected vaccine that contains three inactivated (killed) strains of the flu virus expected to circulate in the U.S. in the current flu season. This years vaccine is designed to protect against A/New Caledonia/20/199 (H1N1)-like, A/Wisconsin/67/2005 (H3N2)-like, and B/Malaysia/2506/2004-like viruses. Since the flu strains mutate, a new vaccine is developed each year.
Flu shots are recommended to people who are at high risk of complications from influenza: children 6 to 59 months, people 50 and older, pregnant women and those with chronic medical conditions. A flu shot is also recommended for health care workers and family members or caregivers of those who in a high risk group.
After getting the flu shot, it takes about two weeks to develop enough protective antibodies against those strains of the flu. In the U.S., flu season can start as early as October. So the best time to get vaccinated is during October and November. If a person comes into contact with one of the strains before then, there is a good chance of becoming sick. Health experts also caution the flu shot is not a guarantee against influenza because a person could be infected with a strain of the flu not included in the vaccine.
In the past few years, the supply of the flu vaccine has been uncertain and several shortages were reported across the country. This year, the CDC estimates more than 100 million doses of the vaccine will be available (19 million more than were available last year). About 75 million doses are expected to be distributed to health care professionals by the end of October.
Another Option: The Nasal Vaccine
In June 2003, the FDA approved another option for flu prevention - the nasal spray flu vaccine (FluMistŪ). The nasal flu vaccine protects against the same strains of the flu virus as the flu shot. However, the spray contains live, but weakened forms of the viruses. And instead of an injection, the vaccine is delivered directly into the respiratory passages by spraying it into the nose.
FluMist is currently approved for use in healthy people five to 49. Further testing needs to be done before it can be approved for use in older adults. Since the nasal spray contains a live form of the virus, there is a slight risk it can cause minor symptoms. Therefore, the nasal form of the vaccine is not recommended for people with chronic health problems, pregnant women, children younger than 5, patients with weakened immune systems, children on long-term aspirin treatment and patients with a history of Guillain-Barre Syndrome.
In the past few years, when the flu shot was in short supply, many health experts were recommending the nasal flu vaccine as an alternative for some patients. There is some research that suggests the nasal flu vaccine may offer better protection in children than a flu shot. James King, M.D., Pediatrician at the University of Maryland Medical Center, says thats probably because the spray is made with a live version of the virus, which gives the bodys immune system a more complete "picture" of the virus for future recognition. In addition, many patients prefer the spray because they dislike getting an injection.
Health experts warn both vaccines are initially grown in an egg culture. So neither form should be given to anyone with an allergy to eggs. Patients who have had a previous reaction to a flu shot should talk with their health care provider before getting any flu vaccine this year.
AUDIENCE INQUIRY
For information about FluMistŪ: http://www.flumist.com/
For general information on the flu, prevention and treatment:
Centers for Disease Control and Prevention, http://www.cdc.gov/flu
National Institute of Allergy and Infectious Diseases, http://www.niaid.nih.gov/publications/flu.htm
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