Trying to decide whether or not to get your flu shot this year? Maybe you have questions about why exactly you need to get the vaccination every year, when’s the best time to do it, or if there are nasty side effects. The Centers for Disease Control and Prevention (CDC) provides some answers.
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5 common questions
1. I hate shots. Won’t it hurt? The very minor pain of a flu shot is nothing compared to the suffering that can be caused by the flu. The flu can make you very sick for several days, send you to the hospital, or worse. For most healthy, non-pregnant people ages 2 through 49 years old, the nasal-spray flu vaccine is a great choice for people who don’t like shots. Either way, a shot or spray can prevent you from catching the flu. So, whatever little discomfort you feel from the minor side effects of the flu vaccine is worthwhile to avoid the flu.
2. Why do some people not feel well after getting the seasonal flu shot? The most common side effect of seasonal flu shots in adults has been soreness at the spot where the shot was given, which usually lasts less than two days. The soreness is often caused by a person’s immune system making protective antibodies to the killed viruses in the vaccine. These antibodies are what allow the body to fight against flu. The needle stick may also cause some soreness at the injection site. According to the Advisory Committee on Immunization Practices (ACIP), rare symptoms include fever, muscle pain, and feelings of discomfort or weakness. If these problems occur, they are very uncommon and usually begin soon after the shot and last one to two days.
3. Does getting vaccinated against seasonal flu early in the season pose a risk that immunity may wane before the end of the season? No. Seasonal flu vaccination provides protection against the influenza strains contained in the vaccine through one influenza season. Vaccination can begin as soon as vaccine is available. So except for some children, only one dose of vaccine is needed.
4. Is it too late to get vaccinated after Thanksgiving (or the end of November)? No. Vaccination can still be beneficial as long as influenza viruses are circulating. CDC recommends that providers begin to offer influenza vaccination as soon as vaccine becomes available in the fall, but if you have not been vaccinated by Thanksgiving (or the end of November), it can still be protective to get vaccinated in December or later. Influenza is unpredictable and seasons can vary. Seasonal influenza disease usually peaks in January or February most years, but disease can occur as late as May.
5. Why do I need a flu vaccine every year? A flu vaccine is needed every year because flu viruses are constantly changing. It’s not unusual for new flu viruses to appear each year. The flu vaccine is formulated each year to keep up with the flu viruses as they change. Also, multiple studies conducted over different seasons and across vaccine types and influenza virus subtypes have shown that the body’s immunity to influenza viruses (acquired either through natural infection or vaccination) declines over time. Getting vaccinated each year provides the best protection against influenza throughout flu season.