When to Get Your Flu Shot for 2022/2023

No doubt your texts and email inboxes are filled with pharmacy and physicians’ office notices that flu shots are now available. But timing when to get your flu shot this flu season can be a little tricky. 

Unlike some vaccines which give you years of protection—you only need a tetanus shot every 10 years, for example—protection from the flu vaccine falls by 18% every 28 days after you get the shot.

The problem is that the start, duration, and end of each flu season doesn’t have an exact trajectory, making when you should get the vaccine an inexact science.

In the U.S., influenza season generally runs from October through March. But last year, there were still quite a few cases reported to the Centers for Disease Control and Prevention (CDC) in June.

The moving target of flu season’s start date across the country, as well as the time it takes to vaccinate hundreds of millions of people, makes it difficult to optimize the timing of your vaccine.

Ideally, the CDC says everyone who is eligible for a flu shot should be vaccinated by the end of October. But that protection will wane in the subsequent months.

Amesh Adalja, MD, senior scholar at the Center for Health Security at the Johns Hopkins Bloomberg School of Public Health, still recommends that people get their flu vaccines in October.

“If the only time a person can get a flu shot is before October, [that’s] suboptimal,” he told Verywell. “But it’s still worth doing for the level of protection it will confer for the early part of the season.”

Flu Season May Be Earlier This Year

This year, CDC data from September shows some states are getting an early start on flu season; Delaware, New Mexico, Texas, and Georgia have each reported cases.

This isn’t totally unexpected. In the southern hemisphere—where flu season begins and ends months earlier than in the northern hemisphere—the 2022 flu season began earlier than expected and produced more severe cases than usual.

“That can be a predictor for what we’ll face,” Kathleen Neuzil, MD, MPH, Director of the Center for Vaccine Development and Global Health at the University of Maryland School of Medicine and Vice President of the National Foundation for Infectious Diseases, told Verywell. “Plus, fewer people in the U.S. are wearing masks now, which could lower protection against the flu and increase transmission. The last two years have seen fewer flu cases than in some previous years, which may have been due to so many people wearing masks during the pandemic.”

It’s important to note that in spite of a potentially early flu season, most experts are sticking with October as the earliest time to get vaccinated. Some experts even suggest waiting until early November.

“It surprises me to see flu cases already. Normally, we start to see flu a little bit later,” Pedro Piedra, MD, professor of molecular virology, microbiology, and pediatrics at Baylor College of Medicine, told Verywell. “I don’t know if this is an early sign about what is in store this flu season, but it is a sign that we need to put vaccines on our horizon.”

Piedra recommends keeping an eye on flu cases in your area. If there is an indication of increase, it’s a good time to get your shot. You can find flu surveillance information on the local health department directory hosted by the National Association of County and City Health Officials.

Almost Everyone Needs a Flu Shot

The CDC recommends that everyone 6 months and older get a flu vaccine each year “with rare exceptions.” Those exceptions include: 

• People with severe, life-threatening allergies to any ingredient in a flu vaccine (other than egg proteins)
• People who have had a severe allergic reaction to a dose of influenza vaccine

Don’t assume that you can’t get the flu shot if you are allergic to eggs, once a well-held belief. According to the CDC, if your flu shot reaction was a case of hives, you should still get the vaccine.

If you had a more severe reaction, such as feeling faint or difficulty breathing, you should get the flu shot under a healthcare provider’s supervision.