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What’s new with the flu shot?

November 13, 2017

About the Author

photo of Dominic Wu, MD

Dominic Wu, MD, Contributing Editor

Dominic Wu, MD, completed his undergraduate studies and medical school at Brown University and was elected to the AOA honor medical society. At Brown, he focused his studies on human biology, public health, and comparative anatomy/paleontology. … See Full Bio
View all posts by Dominic Wu, MD


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Jim Fraser
December 31, 2017

Is it advisable to get a flu shot early in October, and another flu shot later, say in February?


Herta funk
November 18, 2017

Flu shot is not recommended for copd it can cause lung infections. Do
You agree?

Dominic Wu, MD
November 28, 2017

Thank you for your question. The flu vaccine that we typically use does not contain live virus. Therefore, you should not be infected from the vaccine itself.

People with COPD are at an increased risk of developing complications if they do get infected with the influenza virus, therefore I would recommend even more that you get the vaccine. You may feel a little “off” after you get the vaccine with muscle soreness at the injection site, maybe fatigue, which is usually a normal reaction to getting vaccinated as your body’s immune system ramps up to fight the vaccine so it can protect you against a full-on attack.

Here is some more detail about flu vaccines you might find helpful!

Bob Freeman
November 17, 2017

How is the average lay person (i.e., me) supposed to make a timing decision based on your advice? “Get a flu shot before the flu season starts… which is often around December.” How are we supposed to know when THIS flu season starts? Or should we just guess that the optimal time is the last week of November because “…protection against the flu then decreases every month.” By how much? C’mon, doc, you’re the expert – why are you making lay people guess at the right timing?

Dominic Wu, MD
November 28, 2017

Thank you for your comment. It is difficult each year to guess when the flu season will officially “start”. Technically the flu virus is around year-round, especially in tropical countries, so you can always pick it up from travelers or if you travel.

However, we tend to think the season typically picks up around mid November-December, peaking a little later into winter in January and February. Of course this changes every year. The season has started in the US, with confirmed strains so far mostly covered by our Quadrivalent vaccine.

If you want more specific details about how the flu season is going in the US, I would encourage you to follow the CDC weekly flu surveillance reports that can be found on their website:

November 13, 2017

How many potential strains of the flu can one get and what are the chances you will get the correct immunization for the correct strain?


Dominic Wu, MD
November 28, 2017

Hi gilbert,

Thanks for your question. According to CDC data, the trivalent flu vaccines in the US this season include influenza strains: A/Michigan (H1N1)-like, A/Hong Kong (H3N2)-like, B/Brisbane Victoria Lineage. The Quadrivalent vaccine contains the above as well as Influenza B/Phuket Yamagata lineage.

Influenza activity has been increasing the past few weeks. In brief, So far according to surveillance data, positive influenza specimens have been mostly covered by the Quadrivalent vaccine.

More specifically, positive strains have been: A (H1N1) and A(H3N2) in same genetic clade to reference virus in the vaccine. There has also been B Victoria Lineage in the same genetic clade as B/Brisbane and B Yamagata lineage in the same genetic clade as B/Phuket.


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