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Best flu protection

Published October 7th, 2021

Best Protection Against the Flu

Yearly vaccines are the best way to protect yourself against the flu and the serious complications it can cause. Considering the continued COVID-19 pandemic and the increased infectiousness of the Delta variant, it’s particularly important to protect yourself and the people around you during the 2021/22 flu season while helping to reduce the strain on the healthcare system. 

In a similar pattern to last year, the flu and the COVID-19 viruses are expected to circulate simultaneously. It is highly recommended  you receive the flu vaccine this year given the known risk of contracting both influenza and SARs-CoV2 viruses at the same time and the potential confusion associated with not knowing which virus is causing your symptoms. Vaccination is particularly important for vulnerable populations who are at higher risk of developing serious flu and/or COVID-19 complications.

We’ve compiled answers to the following frequently asked questions to help you make an informed choice about getting the flu vaccine.

Are flu vaccines effective?

The effectiveness of the flu vaccine varies from season to season. The overall effectiveness depends mainly on how well the flu strains represented in the vaccines match the strains that are circulating throughout flu season, as well as the health and age of the person being vaccinated. According to the CDC, the flu vaccine reduces the risk of illness by about 40-60% during seasons when the vaccines are well-matched against the circulating flu viruses. In addition, a 2021 study showed the flu vaccine lowered ICU admissions by 26% and reduced death by 31% in adults.1

Are the flu vaccines safe? Yes. Flu vaccines are considered safe and well-tolerated, with hundreds of millions of Americans receiving the flu shot over the past 50 years. Mild side effects such as soreness where the shot was injected, low grade fever, or muscle aches are common but short-lived. As with any vaccine, you should contact a medical provider if serious symptoms develop, such as a high fever or signs of a severe allergic reaction.

Flu vaccines are considered safe and well-tolerated, with hundreds of millions of Americans receiving the flu shot over the past 50 years.

If I got the flu vaccine last year, do I need to get it again?

It is important to get a flu shot every year, for two main reasons. The first is that, similar to the COVID-19 vaccines, the effectiveness of the flu vaccine can diminish over time. The second is that new strains of the flu emerge each year, and the vaccines are updated to optimize their effectiveness. This season, all flu vaccines have been designed to protect against the four flu viruses that researchers have predicted will be most common.

When is the ideal time to get the flu vaccine?

The ideal time to get the flu vaccine is from mid-September through October, as it takes two weeks for the vaccine to reach maximum efficacy and it typically provides about six months of protection (sufficient for coverage through the flu season running November-May).

Is there a specific order in which I should get my flu and COVID-19 shot?

The CDC states that the flu and COVID-19 vaccines can be given together, and a recent study2 supports that co-administration of these two vaccines is safe and produces an effective immune response against both viruses. If you have not yet received your COVID-19 vaccine or are currently eligible for a COVID-19 booster shot, you can get both your COVID-19 and your flu vaccine at the same time. This approach has the benefits of increased convenience and reduced burden on the healthcare system. However, separating the two vaccines out by at least two weeks may lessen the risk of increased side effects and, if side effects do occur, allows you to discern which vaccine was the cause. Whichever approach you choose, most important is that you receive both vaccines, so just get vaccinated however is right for you! If you are due for both vaccines but prefer not to get them at the same time, we suggest prioritizing the COVID-19 shot first given the higher morbidity and mortality of COVID-19 compared to the flu, as well as the continued Delta surge.

* Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.

1          Ferdinands, J. M. et al. Does influenza vaccination attenuate the severity of breakthrough infections? A narrative review and recommendations for further research. Vaccine 39, 3678-3695, doi:10.1016/j.vaccine.2021.05.011 (2021).

2          Lazarus, R. et al. The Safety and Immunogenicity of Concomitant Administration of COVID-19 Vaccines (ChAdOx1 or BNT162b2) with Seasonal Influenza Vaccines in Adults: A Phase IV, Multicentre Randomised Controlled Trial with Blinding (ComFluCOV).

About the Authors

Sheley Baylon, PharmD

Director, Research & Head of Pharmacology

Sheley Baylon, PharmD is a licensed doctor of pharmacology with eight years experience in pharmaceuticals and laboratory research.

Dave Mann, PhD

Director, Research

Dr. Mann brings over 20 years of therapeutics development experience in the biotechnology industry, spanning small molecule, stem cell, and gene therapies from discovery into clinical trials.