Rochester, Minnesota - American health experts predict a particularly active and severe flu season, which means  it's especially important to get a flu shot this year.

"Everybody should be concerned about influenza," Dr. Vandana Bhide, an internal medicine specialist at Mayo Clinic, says.

Every fall health experts urge Americans to get vaccinated, but Dr. Bhide says every year there are people who decide they don't need to get a flu shot.

"The bottom line is, really, anybody over the age of 6 months should be considered for an influenza vaccine," Dr. Bhide says.

She says American health officials make educated assumptions about what to expect from flu season based on how the flu season has been in the Southern Hemisphere. Flu season south of the equator is generally the opposite time of year as it is in the Northern Hemisphere.

Dr. Bhide says not only has it been a very active flu season in the Southern Hemisphere, but it has also been a particularly severe one.

"People who have influenza actually have a more severe version of it," Dr. Bhide says. "So their symptoms are worse. There's a higher risk of complications and a higher risk of death in some cases."

Dr. Bhide says the 2017 flu vaccine covers the strains that have been particularly bad in the Southern Hemisphere. That's why she says it's especially important for people to get a flu shot.

"Influenza is around all the time, so it's never too late to get your flu shot," Dr. Bhide says.

It's also never too early.