Ask the Doc: Flu Shot 101

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Approved by the What’s Up Moms Medical Advisory Board

As a pediatrician, I get a lot of questions about the flu vaccine. In the interest of clearing up some common misconceptions and answering some of the questions I get at this time of year, I’m breaking down the basics.

“My kids are healthy, so they don’t really need the vaccine.” 

While high-risk groups (such as kids under four and those with asthma or other chronic diseases) are especially vulnerable to influenza and the most in need of protection, the flu vaccine is really recommended for everyone. About half of children who develop the most severe complications from influenza had no previous medical conditions, so it’s all about minimizing risk as much as possible.

“It’s too early/ too late in the season for the vaccine.”

Ideally, the best time to get the flu shot is by the end of October, so that you can have full protection before the flu season even starts. Each year is a little different, but flu season typically lasts from mid/late November until early April. It takes about two weeks post-vaccination for antibodies to develop and provide protection. Having said that, it’s not really too late to get the vaccine as long as flu season is still at play, so my practice will usually vaccinate at least into March.

“Last year I got the flu vaccine and still got the flu.”

While it’s possible to get the vaccine and still get influenza, it’s worth noting that the “stomach flu” is not influenza, so the vaccine does nothing to prevent stomach bugs. The vaccine also doesn’t protect against the common cold and other viruses that tend to circulate in the wintertime. The goal of the flu shot is not to ensure that your child doesn’t get sick in the winter, it’s to decrease the chances that they’ll fall ill with the influenza virus specifically.

It’s true that the flu vaccine’s effectiveness varies from year to year. To create the flu shot, scientists need to anticipate which strains they think will be circulating. But even in an “off” year, the flu vaccine is still the single best way to prevent the flu and its complications. The CDC estimates that for the 2017-2018 influenza season, the vaccine prevented an estimated seven million flu illnesses, 109,000 flu hospitalizations, and 8,000 deaths.

“I’m worried my child will get the flu from the shot.”

Like any vaccine, the flu vaccine can lead to muscle aches, fever and fatigue for a few days after getting it, although the majority of people have no side effects. But the injection is a killed version of the influenza virus, so you can’t get the flu from the flu shot itself. The intra-nasal spray version of the vaccine is a little more complicated; it uses a live, weakened virus, so it can cause some runny nose but also cannot lead to full-blown influenza, since the weakened virus is cold-adapted, meaning it can only live in cold environments like the nose and can’t spread to the rest of the body.

“What’s the deal with the intranasal (spray) vaccine, anyway?”

The intra-nasal flu vaccine, commonly known as FluMist, was a fan favorite for many years for those kids and parents eager to avoid the shot. Sadly, a review of data for the 2015-16 season showed that it wasn’t effective, so it wasn’t recommended or used for the next couple of years. It’s now passed the tests to be considered an effective option for vaccination, but due to manufacturing constraints, there’s a shortage this season so it will probably be hard to find.

“My child has an egg allergy so he/she can’t receive the shot.”

We used to recommend that anyone with an egg allergy avoid the flu vaccine because the egg-based manufacturing process was thought to leave trace amounts of egg protein in vaccines. Turns out the odds of an allergic reaction are so low that they’re considered negligible (1.3 in a million). As a “just-in-case” precaution, those with a history of anaphylactic reaction to eggs are advised to get their flu shot in an environment in which they can be monitored by a qualified health professional (for example, in their pediatrician’s office, rather than a CVS or other such clinic).

“I already had influenza, so I don’t need to get vaccinated.”

Since the strains tend to change each year, getting the flu doesn’t provide lasting immunity. Plus, the vaccine protects against three or four different strains. I’ve had several patients with the misfortune of getting a bad case of Influenza A, only to show up in the office the next month with Influenza B.

“My kid hates shots so I just want to avoid putting him/her through that.”

As a mom I can relate. My kids are not fans. I do not enjoy watching them dissolve into tears one by one, despite my best efforts to help them relax. But the pain of the poke pales in comparison to the suffering that I see when children show up with a bad case of influenza. And while it won’t take the pain away completely, there are some evidence-based ways to minimize discomfort with the shot: distraction (like watching videos), simultaneously giving something sweet, and ice packs prior to the injection.

In short, the flu vaccine isn’t a perfect one, but it’s our best shot at fighting the flu and keeping kids — and families — safer during the winter season.

Dr. Hovav is a board-certified Pediatrician in CA and Fellow of the American Academy of Pediatrics. She lives in Sherman Oaks with her husband and three young children, boy/girl twins and their wanna-be-a-triplet little brother. She can be found caring for patients in Studio City at Beverly Hills Pediatrics -The Valley.