With flu season approaching, and the possibility of another surge of Covid cases this fall, many Americans are wondering when is the best time to get the flu vaccine, and if it is okay to double up and receive both the seasonal flu vaccine and new omicron.

The CDC says it is okay to get a flu vaccine and Covid-19 shot at the same time.

People have begun getting immunized with both shots at the same time, as a result of the vaccines being offered as a package deal.

According to Theodora Hatziioannou, a professor at Rockefeller University, not all public health experts think this is the best approach.

It would be better for the average person to have it later.

Hatziioannou tells CNBC Make It that the best time to get a flu shot is at the beginning of the flu season.

When cases historically start to increase in your community, it is important to look at data from recent years.

Four weeks before the start of flu season is the ideal time to get your vaccine because you will have the best response.

The flu season in New York and several other areas with the same geographical latitude starts in December and lasts until March. It's too early.

The best time to get a flu shot is at the end of October or early November.

If you get the vaccine too early, you'll have less immunity at the end of the flu season.

Hatziioannou says that he would definitely get both shots this year.

You don't want to get the flu while Covid's going around, and you don't want to get the disease while the flu is going around. I can see how a double-whammy would be really bad.

Mark Conroy is an emergency medicine physician at the Ohio State University Wexner Medical Center.

There haven't been any studies looking at the side effects of the flu shot and the omicron vaccine together.

If you want to get a flu shot later in the year, then you should get a dual appointment.

The biggest risk is if you don't get them at the same time. If you have the chance, you should get the vaccine over not getting it.

He suggests waiting until mid- to late- October or the beginning of November to get your flu shot.

People should get the omicron booster as soon as possible. September is a bit early for the flu shot because Covid is around enough. It's a good idea to get it later in the fall.

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