More Options with More Convenience for Influenza Vaccines

Though it can lead to confusion, I can’t think of a situation where having more options as to vaccines wasn’t a good thing.

For the COVID-19 vaccines, having the Novavax option was a good solution for those who have fears stoked by prominent antivaxxers who have spread all kinds of disinformation about the mRNA vaccines altering our DNA (this would flunk them out of the first year of medical school) or a completely made-up assertion, unfortunately perpetuated by a state public health official and amplified by this same group of disinformation purveyors, that the Pfizer vaccine contains DNA coding for the Simian Virus 40 protein (it doesn’t, and even if it did, the vaccine production process would destroy the DNA to the point that the protein wouldn’t be capable of coding for the production of the protein) and that this will now lead to the vaccine causing cancer (it hasn’t and won’t). But, it is understandable that some of the lay public has heard such disinformation and is hesitant to get the vaccines as a result. Therefore, Novavax, which is based on protein technology that has been used safely in the U.S. and around the world for decades, may be a good choice for these folks to put their minds to rest since no genetic material (RNA or DNA) is used in the process of making the vaccine, nor is any contained in the vaccine.

Novavax is also a welcome addition to our COVID-19 vaccine offerings for those who have had significant reactogenicity (side effects like sore arm, swelling or redness at the injection site, fever, headache, muscle aches, etc.) since Novavax has repeatedly been shown to have far less reactogenicity.

On the flu vaccine front, the FDA gave us great news two days ago when it approved a nasal spray influenza vaccine that has been and continues to be available through health care providers, but now can be purchased at the pharmacy with a prescription and taken home for self-administration. This is the first flu vaccine that has been approved for self-administration, which may improve the convenience and access to the vaccine. Also, there are not an insignificant number of people (and especially children) who are afraid of needles, so this vaccine may encourage them to get the influenza vaccine that they might otherwise not get.

This influenza vaccine is called FluMist. It was first approved in 2003 (in 2003, the lower end of the age limit was 5 years, but in 2007, the FDA lowered that to 2 years of age) and covers human seasonal influenza A and B viruses (not the avian influenza or bird flu that you may have seen in the news lately), and is approved for persons aged 2 – 49 (that may seem strange to you; more on that below).

One difference between the nasal vaccine and the “flu shots” is that the nasal vaccine contains an attenuated (weakened) form of live influenza virus. Because the virus is not “killed” or “inactivated,” it does produce a more vigorous immune response in the nasal passages, and as a result can cause low-grade fever in children (particularly under age 6) and in all recipients, the most common side effects are runny nose and nasal congestion. Adults who report side effects are more likely to report a sore throat.

We are told that for those who wish to self-administer the nasal vaccine (age 18 and over) or who wish to administer the vaccine to a person under the age of 18 in their household, you will go to the website of a third-party online pharmacy and fill out a screening and eligibility assessment. If eligibility is confirmed, the pharmacy will write the prescription and ship the vaccine to the address provided.

Who should not receive the nasal spray influenza vaccine?

• Children under the age of 2 years;
• Adults 50 years old and older;
• Anyone with a history of severe allergic reactions to an ingredient of the vaccine or to a previous dose of any of the influenza vaccines;
• Children ages 2 years – 17 years of age who are on aspirin or salicylate-containing medications (these children are at increased risk for Reye’s Syndrome with live virus);
• Children ages 2 years – 4 years with a history of asthma or wheezing in the prior year.
• Anyone who is immunocompromised (they should receive the flu shots with inactivated virus);
• Anyone who resides with severely immunocompromised persons unless they can isolate themselves for a week following administration of the vaccine;
• People who’s spleen has been removed (usually following trauma like a car accident) or who have a non-functioning spleen (for example, sickle cell disease);
• Anyone who is pregnant (this is precautionary; the vaccine does not appear to be absorbed systemically and there has been no documented transmission or adverse effects to the fetus, but it is considered prudent to administer the inactivated influenza vaccine to pregnant women);
• Anyone with a CSF (cerebral spinal fluid) leak connecting to their mouth, nose, ear, or other place within the skull (for example, as a result of surgery or trauma);
• Persons with cochlear implants;
• Anyone who has recently taken influenza antivirals (oseltamivir or zanamivir within 48 hours; peramivir within 5 days; or baloxavir within 17 days). This is because influenza antivirals can reduce the effectiveness of a live virus vaccine.

Further, if you are older than 5 years old with asthma; have underlying medical conditions; have an acute illness, especially another infection; or have a history of Guillain-Barre Syndrome, talk to your doctor before ordering the FluMist vaccine. There was an elevated risk for Guillain-Barre Syndrome with the 1976 swine flu vaccine, but no association has been noted with vaccines subsequent to 1976 (we have not used swine flu viruses for vaccines since 1976). Thus, the risk for this condition appears minimal, but we nevertheless would generally not administer this vaccine to anyone who has been experiencing or recovering from Guillain-Barre Syndrome within the prior 6 weeks.

The age cut-off of 49 years for FluMist will seem strange to some readers, as this is unusual. As far as I can tell, it is based upon one study that did not show effectiveness of the vaccine in those in the age group of 50 – 64 years. There are certainly methodological criticisms that can be made about this particular study, but nevertheless, absent another study demonstrating effectiveness in this age group, the age restriction is appropriate. Further, those who are ages 65 years and older should receive the high dose or recombinant influenza vaccines (FluMist only comes in one dosage formulation). Suitable vaccines for those 65 years and older include:

• High-dose inactivated influenza vaccine (HD-IIV3, Fluzone High-Dose)
• Recombinant influenza vaccine (RIV3, Flublok) or
• Adjuvanted inactivated influenza vaccine (allV3, Fluad).

Finally, keep in mind that the immunity from all influenza vaccines wanes and therefore, even though it is currently being offered and promoted by some pharmacies, it is best to wait until we start seeing rising cases of influenza where you live before getting the vaccine so that it will give you the greatest protection for the entire flu season, which can certainly last as long as 6 months. If you follow me on X or on the Idaho Matters radio show, I will let you know when I think the ideal time is to get your vaccines as we watch the influenza activity here in Idaho and around the country.