The flu shot is only as good as the educated guesses of a group of vaccine researchers across the globe. Every February, they try to predict which flu viruses will work their evil during the next fall and winter. Their three top choices are put into the vaccine. The CDC claims that vaccine will be 70 to 90 percent effective against just those strains of flu. “We hope that these smart scientists who get together with the vaccine producers make the right call,” says immunologist Randy Horwitz, MD, medical director of the University of Arizonas School for Integrative Medicine. But sometimes they dont, partly because the virus mutates from year to year. In 2003–2004, the CDC admitted that it completely missed the virulent Fujian flu strain that hit hard that winter.
Even if it doesnt work, it cant hurt to get the shot, right? For most people that may be true. Millions of vaccinations are administered each year, but since 1991, only about 26,000 adverse events have been reported to the Vaccine Adverse Events Reporting System (VAERS). Most of those were fever, rash, headaches, hives, or, very rarely, seizures. The most common side effect is swelling at the injection site on your arm. And any bad reactions, thought to be your immune systems way of gearing up after the exposure to dead virus particles in the vaccine, typically ease after a few days. (Manufacturers are required to verify that each batch of vaccine used for injections contains no live flu viruses. But people with egg allergies shouldnt get the shot because the vaccine is manufactured using eggs.)
Is the nasal vaccine better than the typical shot?
Hard to say, but the latest news on FluMist may leave you skeptical. Earlier this year the manufacturer, MedImmune, had trouble getting an OK to market the vaccine for kids under 5. The U.S. Food and Drug Administration found ongoing problems at the companys plant in Great Britainbacterial and fungal contamination as well as the use of a disinfectant banned by the European Union. Eventually, the company fixed the problems and, in September, received approval for the under-5 set.
The flu kills. Each year nearly 40,000 people in the United States die from flu complications like pneumonia and heart failure. And more than 200,000 are hospitalized due to flu. The people at highest risk have lowered ?defenses: children ages 6 months to 5 years, pregnant women, people older than 50, and anyone with a chronic condition like asthma, diabetes, and heart or blood disorders. The CDC recommends they all get vaccinated.
You may remember the panic over vaccine shortages in 2004, when a major flu-vaccine manufacturer, Chiron, was unable to deliver 50 million doses of the vaccine due to bacterial contamination. Some experts speculate that the shortage encouraged people to stay away from the vaccine in the following years. But Curtis Allen, spokesperson for the CDC, says a shortage is unlikely this year. Manufacturers are promising a record number of doses (132 million), although they wont all be available at once.
Now, before the flu season really kicks in from December to March, experts say. It takes about two weeks after vaccination for your body to build up enough antibodies to protect you.
For sure. There are more than 200 cold viruses, they mutate a lot, and virtually everybody comes down with one from time to time. Although the worst colds might feel like the flu, lots of people say they have the flu when they really dont. Two years ago, only 13 percent of people who were tested after reporting flulike illnesses actually had the real thing.
Nobody really knows. The 1918 pandemic seemed to start like any old flu season, but within a few months the virus had mutated into a monster that killed healthy adults within a day. Like most flus, it may have originated in birds. Thats why experts worry that todays avian flu may turn into a global epidemic. But, un-like the 1918 strain, it hasnt spread readily from person to person. And while the regular flu shot wont protect you against avian flu (its a different strain of the virus), consider this: Researchers are finding that millions of people have been infected with avian flu without suffering serious complications.