The flu vaccine is the best way to protect yourself from the influenza virus. You should get one every year, unless you have a medical reason not to.Flu season can begin as early as October and last as late as May. It’s best to get the vaccine as soon as it becomes available each fall. But you can still get vaccinated in January or later. The flu shot becomes effective about 2 weeks after you get it.
Can the vaccine give me the flu?
No, The viruses in the flu shot are dead. Even the nasal spray, which has a weak version of the flu virus, cannot give you the flu.
Why do I need to get vaccinated every year?
New flu vaccines are released every year to keep up with rapidly adapting flu viruses. Because flu viruses evolve so quickly, last year's vaccine may not protect you from this year's viruses.After vaccination, your immune system produces antibodies that will protect you from the vaccine viruses. In general, though, antibody levels start to decline over time — another reason to get a flu shot every year.
What are the possible side effects?
Most people have no problems from the vaccine.If you get the flu shot, you might have a mild fever and feel tired or achy afterward. Some people also have soreness, redness, or swelling where they got their shot. These problems aren’t serious and don’t last long. Serious side effects are rare. If they do happen, it's within a few minutes to a few hours after you get the shot. Call your doctor right away if you have trouble breathing, hives, feel weak or dizzy, or have a fast heartbeat afterward. If you get the nasal spray, you might have side effects like a runny nose, headache, cough, and sore throat. These are milder and shorter than the flu.
Should I talk to my doctor before I get a flu shot?
Some people should make sure it’s OK to get vaccinated. Ask your doctor or pharmacist first if:
- You’ve had a life-threatening allergic reaction to a flu shot in the past.
- You’ve had Guillain-Barre syndrome that happened after you got the flu vaccine. That’s a disorder in which the body's immune system attacks part of the nervous system.
- You’re very ill. If you have a mild illness, it's OK to get vaccinated. Otherwise, talk to your doctor or pharmacist first.
- You’ve had allergy to egg: Most types of flu vaccines contain a small amount of egg protein. If you have an egg allergy, you can receive the flu shot without any additional precautions.
Who should get the flu vaccine?
The CDC recommends annual influenza vaccinations for everyone age 6 months or older. Vaccination is especially important for people at high risk of influenza complications, including:
- Pregnant women
- Older adults
- Young children
Children between 6 months and 8 years may need two doses of the flu vaccine, given at least four weeks apart, to be fully protected. Check with your child's health care provider.Chronic medical conditions also can increase your risk of influenza complications. Examples include:
- Cancer or cancer treatment
- Chronic obstructive pulmonary disease (COPD)
- Cystic fibrosis
- Kidney or liver disease
References:“Flu Shot.” Flu Shot: The Vaccine and Its Side Effects, 12 July 2017.
“Flu Shot.” Flu Shot: Your Best Bet for Avoiding Influenza, 19 Sept. 2017