Flu shots:With rare exceptions, everyone should get one

September 26, 2016

Illness from the flu puts millions of infants and children in the U.S. at risk every year. We are approaching the start of the 2016 flu season and now is the time to talk about the flu vaccine. You might be thinking, "I don't give my kids a flu shot" or "flu shots don't actually work," but I'm hoping to share some information that will change your mind.

Before we go further, however, let me point out key changes recently announced for this flu season:

  • The live-attenuated intranasal vaccine (the liquid form, which is sprayed up the nose) will not be available this year. As part of the surveillance surrounding vaccines and their effectiveness, it was found that this version has not protected as well as the inactivated (non-live virus) version, which comes as a shot.
  • Having an egg allergy is no longer a reason to not get a flu shot! If someone has had a mild allergic response (like hives) after eating eggs or an egg product, they can get this year's flu shot without close monitoring. If someone has had a more severe allergic reaction (swelling of lips/tongue, difficulty breathing or vomiting), they can still get the shot -- but it should be given in an area such as a clinic, hospital or ER where the person can be monitored for at least 30 minutes afterward. You should discuss this with your provider/clinic before assuming this can be done in their office.

Flu can lead to complications

Ok, back to talking about why nearly everyone -- but especially children and pregnant women -- should get a flu shot. The short answer is that it helps to protect us from getting sick with the flu. More importantly, it helps protect against the complications that go along with getting really sick from the flu.

A severe bout can lead to lots of missed time at school or work, and even hospitalization. Some children get pneumonia due to the flu or have severe breakdown of their muscles (myositis). Children with asthma can have an asthma flare requiring medication or hospitalization. And even if your child does get sick with the flu despite getting a shot, the symptoms may be milder or shorter in duration.

Wait. My child could get sick despite a flu shot?

Yup. That's part of the long answer. There are a multitude of flu strains (viruses change more frequently than bacteria) and in order to make a flu shot each year researchers take their best guess as to which strains are going to be the ones that make us sick. They can't select all strains so they try to identify a few and put those into a form for vaccine. So if a different strain shows up, we might not have a defense for it.

To make matters more complicated, some people respond to the vaccines robustly while others may not. For example, the bodies of children under 2 may not mount a large antibody response. This is why it's important for all family members to get vaccinated in order to provide protection to others.

A shot for mom can protect a newborn

Pregnant women are an especially important group when talking about "passive" protection. When moms-to-be get a flu shot during pregnancy, they begin to make antibodies as protection for themselves and then pass those antibodies on to their infant, either through the placenta or after birth through breastfeeding. This is important since infants younger than 6 months are at the greatest risk of hospitalization, complications and death from the flu but are too young to receive their own flu shot.

A study published in JAMA Pediatrics (September 2016) examined this phenomenon in more than 2,000 newborns by dividing pregnant mothers into two groups: One received the flu shot, while the other received a placebo, in this case a saltwater injection. The researchers followed the infants for up to 6 months after they were born to see how they were affected. What they found is that babies born to mothers who got a flu shot got sick significantly less from the flu compared with mothers who did not get a shot. The researchers reinforced this finding by showing that the babies also had levels of protective antibodies through at least the first couple months of life.

Side effects and potential risks

Now it is fair to note that a discussion about the benefits of the flu shot would not be complete if we did not talk about the potential risks. Are there potential side effects associated with the flu shot? Of course – all medications have potential side effects. The key word here is "potential" as the great majority of adults and children suffer no side effects whatsoever.

The No. 1 complication is having a sore arm or leg at the site of injection, possibly even a mild redness to the skin. Infections of the skin or bleeding are not common. Next in line come possible fevers, headaches and nausea. It is important to know that this is not the same as actually having the flu (reminder: there is no live virus in the flu shot) but is thought to be due to the body responding to the vaccine and mounting an immune response. The above complications are typically considered mild, do not require attention and resolve in a matter of days.

Another potential complication is that some children may have a febrile seizure in the setting of fever after vaccination. Febrile seizures are seen in 5 percent of all children aged 6 months to 5 years and are more common with fever due to illness or infection. They usually result from a high fever (above 102.9), typically last less than a minute and don't cause brain injury. An investigation into febrile seizures and flu vaccine showed that there was little to no increased risk unless the vaccine was given in conjunction with the pneumococcal conjugate vaccine (PCV13).

Life-threatening complications rare

Serious complications from the flu shot are fortunately very, very rare. These include a life-threatening allergy (anaphylaxis) that can lead to death without intervention or an illness called Guillan-Barre, a neurological condition that results in weakness in parts of the body. Guillan-Barre is actually seen more frequently following influenza infections, which might help the case for vaccination.

The verdict: Get a shot if you qualify

One way to think of this is that for every 1 million flu shots, one to two severe complications may be seen, but approximately 500,000 cases of flu will be avoided or minimized. Because of this, researchers and physicians uniformly agree that the flu shot is safe and should be given to everyone who qualifies this season.

If you have questions about a flu shot for a child, Swedish Pediatrics can help. Call 1-800-793-3474 to schedule an appointment. If you are pregnant, call Swedish Pregnancy and Childbirth at 206-386-2229.