The Influenza Vaccine: Making the ‘Scary’ a Little Less Scary

I face many challenges in my family practice office when it comes to convincing patients of the need for certain treatments, medications and preventative measures. However nothing is more challenging than trying to convince a patient (or a patient’s parent) who is hesitant on vaccines that they are safe and warranted.  Like most challenges I face in my career, I find that most of this stems from the general public being misinformed or undereducated.  Gone are the days where patients agree to a medical procedure or medication simply because their doctor recommends it. No, that sort of blind faith has long disappeared and what is left behind is a large group of people who would rather do nothing than blindly follow their doctor’s recommendation, especially when they are confused or unknowledgeable about a given topic.

I see this a lot with the influenza vaccine. Between the months of September and March, I regularly hear patients refuse the flu shot. Below is my response to several questions and statements I hear regularly regarding the influenza vaccine.   Hopefully, the information provided will make you a little less hesitant to receive the influenza vaccine and we can make the “scary flu shot” a little less scary.

How are the flu strains chosen for the vaccine?

Throughout the year, thousands of volunteer influenza centers collect data regarding the incidence of influenza and collect specimens from patients who have influenza like illness. In the state of Michigan, the Michigan Department of Health and Human Services (MDHHS) participates in the U.S. Outpatient Influenza-like Illness Surveillance Network. As a sentinel provider, the weekly total number of patients that visit the facility are reported as well as the number of patients with influenza-like illness (fever >100degrees with cough and/or sore throat). Specimens (nasal swab) obtained from patients with influenza-like illness are sent to the MDHHS laboratory for testing. Data obtained from these reports and lab specimens are tested and recorded by the Center for Disease Control and ultimately sent to the World Health Organization. (The CDC publishes weekly influenza reports that are available for review on their website at http://www.cdc.gov/flu/weekly/index.htm).

Twice a year (February for the Northern Hemisphere and September for the Southern Hemisphere), the data is reviewed and recommendations are made by the WHO regarding the composition of the upcoming influenza vaccine.   While the WHO recommends specific viruses for inclusion in the vaccine, in the United States the FDA makes the final decision about which virus strains will be included in the upcoming influenza vaccine.

Once the 3-4 virus strains have been chosen, the viruses must be isolated, grown, tested and mass produced for distribution. Typically most doctor offices receive influenza vaccines in late August for the upcoming influenza season.

I had the flu shot last year, why am I not covered this year?

Influenza viruses change yearly. The actual virus may mutate or strains that were not included in last years vaccine may be predicted to circulate in the upcoming flu season. For instance, lets say that strains A, B, C and D were included in the 2015-2016. But the WHO and CDC predict that strains A, B, Y and Z will be circulating in the 2016-2017 year. You will need an influenza vaccine to protect you from the Y and Z strains since they were not included in the previous year. Furthermore, much like other vaccines, the influenza vaccine does not provide lifetime coverage (this is why you have to get boosters of some vaccines like the tetanus and meningococcal vaccines). Unfortunately, the influenza vaccine typically provides only 12 months of coverage; therefore in order to have ongoing protection, annual vaccination is recommended.

 I never get the flu, why do I need to get it?

My kids have never been in a car accident, but I still put them in their car seats. In other words, consider yourself lucky that you “never” get the flu but just because you haven’t gotten it in the past, does not mean that you are exempt from the virus. Influenza has no prejudice.

I couldn’t tell you the last time I had the stomach flu. I never vomit.

Stop.

No. Please understand that influenza is NOT the same thing as the stomach flu. Influenza is a respiratory virus that causes a fever, cough, sore throat, muscle aches and fatigue. The flu shot does not, I repeat DOES NOT, protect against the stomach flu.

How does the flu shot work?

For a better understanding of this, I plan to write a more detailed post about how vaccines work in general but for now here is a brief explanation…

The flu virus strains are isolated and killed; this means that they cannot cause illness in the body. However, once injected, to the body’s immune system they look threatening. Therefore the immune system builds antibodies against the inactivated virus. If during the influenza season you are exposed to the actual flu virus, your immune system has already created an army of antibodies ready to fight. The real virus is recognized immediately upon entry, attacked and killed before it is able to cause symptoms or illness.

 Can you get the flu from the flu shot?

The flu shot is made from inactivated (also known as killed) strains of the virus. The body’s immune system recognizes the inactivated virus as the actual flu virus and builds antibodies against it, but the vaccine itself cannot cause illness. Think of the flu vaccine as a one of those lifelike wax statues of a celebrity; preferably one like Al-Pacino in Scarface, Anthony Hopkins in Silence of the Lambs or in my worst nightmares, Chucky (*shudder*). These statues look real and would be terrifying if they were real, but since they are ‘inactivated’ they do not pose as a threat.

What most people fail to realize is that the influenza vaccine takes 2 whole weeks before it protects you from the flu virus. (It takes time for your body’s immune system to make all those antibodies!) Therefore, if you get the influenza vaccine on September 1^st but you are exposed to the influenza virus on September 7^th, there is a good chance you will become ill. However, this is not because the flu shot got you sick! The vaccine won’t be effective until September 14^th or so.

Does this help? Is the flu vaccine a little less intimidating to you now? What other questions do you have about the influenza virus and vaccine? Comment below and let me know!

As always, all medical information provided is to serve as a resource and promote broad consumer knowledge on a range of medical topics and is not intended as a substitute for the medical advice of your medical provider.

Resources: Center for Disease Control. www.cdc.gov