How to Respond to Flu Vaccine Doubters

By Sherif Beniameen Mossad, MD, FACP, FIDSA, FAST*

Please note: this is an abridged version of an article originally published in the Cleveland Clinic Journal of Medicine.

The benefits of influenza vaccination are clear to those in the medical community. Yet misinformation and unfounded fears continue to discourage some people from getting a flu shot. During the 2018–2019 influenza season, only 45% of US adults and 63% of children were vaccinated.

What should we tell patients who say no to the flu shot? Here are 12 reasons people give for not wanting to receive the inactivated influenza vaccine, along with some potential responses and comments about the nasal live attenuated vaccine.

Reasons people give for not wanting the influenza vaccine, and potential responses

1. “It doesn’t work for many people.” While the vaccine may not work for some people, it does work for most. Even when it does not prevent influenza, it makes influenza-related illness less severe.
2. “It has been made to target the wrong virus.” Even when vaccine serotypes don’t match circulating virus serotypes, some effectiveness is retained. Some protection is better than none. A universal flu vaccine that does not need to be updated annually is likely several years away.
3. “It makes people sick.” The inactivated vaccine cannot biologically “make people” get influenza, as the virus in the vaccine is inactivated. The nasal live-attenuated vaccine can result in acute upper respiratory tract symptoms, but because it is cold-adapted, it multiplies in the nose, eliciting immunity — but not in the lungs, and thus cannot cause influenza pneumonia.
4. “It causes Guillain-Barré syndrome (GBS).” The increased risk of GBS in the 6 weeks after vaccination reported in 1976 has not been seen in more than 40 influenza seasons since then. The risk is 15 times higher after influenza illness than after influenza vaccination.
5. “I got the flu shot, and I still got sick.” The vaccine is intended to prevent influenza. It does not prevent other viral or bacterial illness that may mimic influenza.
6. “I’m allergic to eggs.” Persons with a history of urticaria after exposure to eggs can receive any influenza vaccine. Persons with a history of angioedema, respiratory distress, light-headedness, or recurrent vomiting, or who required epinephrine or other emergency intervention after exposure to eggs, should receive the vaccine only in an inpatient or outpatient setting, monitored for severe allergic reactions. History of a severe allergic reaction such as anaphylaxis to a previous dose of any influenza vaccine, regardless of the suspected component (e.g., eggs), is a contraindication to influenza vaccination.
7. “I don’t want to put poisonous mercury in my body.” Ethylmercury preservative in influenza vaccine is safe, but methylmercury in fish, if ingested in large quantities, can be toxic to the central nervous system.
8. “I don’t like needles.” Take the nasal flu vaccine.
9. “I don’t want to take anything that can mess with my other medications.” Immunosuppressive drugs may reduce influenza vaccine immunogenicity, but the vaccine does not alter the efficacy of these drugs, other medications, or vaccines.
10. “I’m afraid it will trigger an immune response that will make my asthma worse.” The inactivated influenza vaccine does not precipitate asthma exacerbations. Rather, it prevents 59%–78% of attacks leading to emergency visits or hospitalization. The live-attenuated influenza vaccine is contraindicated in children 2 to 4 years old with asthma.
11. “I had an organ transplant, and I’m afraid the flu shot will cause organ rejection.” Influenza infection — not the vaccine — can precipitate organ rejection.
12. “I’m pregnant, and I don’t want to expose my unborn baby to anything potentially harmful.” The flu vaccine during pregnancy protects you and your infant, since protective antibodies are transmitted through the placenta and can last up to 6 months. After the age of 6 months, the child should get annual influenza vaccination.

Contraindications and precautions to the use of influenza vaccines

Healthcare providers should try to understand the public’s misconceptions about seasonal influenza and influenza vaccines in order to best address them.