If you don’t want to be one of the 40 million Americans who get the flu each year, it’s time to roll up your sleeve.

Everyone 6 months of age or older should have a flu shot by late October, before flu season begins, the U.S. Centers for Disease Control and Prevention recommends. Flu puts hundreds of thousands in the hospital each year and last year it claimed up to 61,000 lives, the CDC estimated.

Even once the flu season is in full swing, it’s not too late to get protected, experts from Rutgers Medical School said. The vaccine covers both influenza A and B strains, and this year’s shot has been tweaked to account for changes in the virus.

“Besides protecting you from common strains of the flu, the vaccine will lessen the severity of symptoms if you contract a strain that was not included,” said Dr. Tanaya Bhowmick, an infectious diseases specialist.

“Having the vaccination will stop the virus from infecting others,” especially vulnerable populations such as the elderly, children and those who have an impaired immune system, she explained in a news release from Rutgers Health.

Bhowmick added that a nasal spray vaccine, FluMist, can be given to people between the ages of 2 and 49, and it’s as effective as a needle.

Her colleague, Dr. David Cennimo, an assistant professor of medicine, said other precautions include staying home for at least 24 hours after your fever breaks; covering your nose and mouth when sneezing or coughing; washing your hands with soap and water after using a tissue; and avoiding touching your eyes, nose and mouth.

It’s also a good idea to skip large public gatherings, he suggested.

Flu can have serious complications, Cennimo said, such as pneumonia; inflammation of the heart, brain or muscles; and organ failure. Seniors and people with chronic conditions are at highest risk of dying, he added.

Flu season lasts from October through May, peaking between December and February, Cennimo said. Because the vaccine’s peak effectiveness lasts about six months, October is prime time for the shot.

And, don’t worry, the vaccine won’t give you the flu, Bhowmick said. But because it exposes you to a weakened form of the virus, you might feel a little sick after getting vaccinated, she added.

More information

Learn more about the flu from the CDC.