What to know about this year's flu shot

Summer weather might still be hanging around but it won’t be long before flu season is upon us. That’s why health officials say that now is the best time to get your flu vaccine.

According to the Centers for Disease Control and Prevention (CDC), adults and children 6 months and older should get vaccinated before the end of October. Since it takes about two weeks to develop immunity after receiving the vaccine, it's generally better to be protected before flu viruses begin circulating in the community. 

However, as long as viruses are still circulating, it’s not too late to get the flu vaccine. Getting vaccinated even in December or later can still provide protection for the rest of the season. 

What to know about the flu vaccine

• The flu vaccine only protects against the flu. Specifically, it protects against the three or four strains used in the vaccine manufacturing process, but it may also provide some protection against related strains of influenza not contained in the vaccine.
• Other respiratory viruses (rhinovirus, for example) may cause flu-like symptoms that can be mistaken for the flu, but aren't the flu virus.
• When you get the flu shot, it also protects others around you by preventing transmission of the influenza virus. This is especially important for people who are unable to get the flu vaccine and for those at a high-risk of developing complications from the flu (infants and young children, elderly, immunocompromised).
• As of 2016, if you have an egg allergy of any severity, you may still receive any licensed, age-appropriate flu vaccine. Talk with a health care professional.
• It’s possible to get the flu even after receiving the vaccine. However, those who receive the vaccine are less likely to be admitted to the hospital or die due to the flu, compared to those who don't get the vaccine.

Age groups that should be vaccinated against the flu

Everyone 6 months and older should be vaccinated against the flu, unless there’s a medical reason why they shouldn’t be.

Children younger than five years old, adults older than 50 (and especially those older than 65), pregnant women, and those with certain chronic medical conditions are especially at risk for bad outcomes from the flu virus, so, keep in mind:

• Children 6 months to 8 years old who need two doses of flu vaccine should get their first dose as soon as possible after the vaccine becomes available, and their second dose at least four weeks later.
• Women who are pregnant can get the vaccine at any time during pregnancy.
• A high-dose vaccine, which contains four times the amount of each strain of influenza compared to the standard-dose vaccine, is available for seniors 65 years and older,. This higher dose of antigen makes the high-dose vaccine more effective in providing protection in this age group. This is because, as we age, our immune systems naturally get weaker. The higher dose has been associated with improved immune response and fewer hospital admissions in older patients due to influenza compared, to the standard-dose vaccine .

Getting a flu shot does not cause you to get the flu 

It’s a myth that getting a flu shot causes you to get the flu. If someone who receives the flu shot ends up getting the flu, there are a few possible explanations:

1. It takes time for the vaccine to work. It’s possible to be exposed to the flu before or shortly after receiving the vaccine and develop symptoms before the vaccine has time to take effect.
2. It’s also important to remember that the vaccine doesn’t contain every possible strain of the flu so you could become sick with a different strain of flu.
3. The vaccine itself may occasionally cause mild flu-like symptoms (low-grade fever, headache, muscle aches) in some people. This is not the flu; this is part of the normal immune response and usually goes away in one to two days. Symptoms are generally much less severe than the real flu.
4. The vaccine doesn’t always prevent the flu, particularly in people with weaker immune systems. However, it usually offers at least some protection and may prevent some of the more severe complications from the flu.  

FluMist is back

This year, the FluMist (intranasal vaccine) is back after a two-year absence. So what’s new this time? The manufacturer has reformulated FluMist and health officials say it will be more effective than the one that was previously used. While there’s no definitive data yet to prove that this new formulation is more effective, preliminary data suggests that it will be. 

So who should get the FluMist? The CDC recommends FluMist as an option for those with a healthy immune system who are 2 to 49 years old. The American Academy of Pediatrics proposes FluMist as a second-line option only in children who refuse or can’t otherwise receive the flu shot.

What makes the FluMist different, other than that there’s no needle involved, is that it has the advantage of creating a better immune response than the inactivated vaccine because it’s more similar to the real flu. But it may not be safe in people who have a weakened immune system. A full list of people who should NOT receive FluMist is available on the 
CDC website. 


Jessica Smith is a specialty practice pharmacist for Infectious Diseases at The Ohio State University Wexner Medical Center.