October the best time to get COVID boosters, flu shots, experts say

With doctor's offices and pharmacies now offering seasonal flu shots and updated COVID-19 boosters, experts are urging Americans to get both, with many saying October is the best time.

While experts say October may be an ideal window to boost immunity, they are also emphasizing the importance of getting vaccinated, period -- whenever you are able. It's safe for people to get both shots during the same visit for added convenience, experts say.

White House COVID coordinator Dr. Ashish Jha told ABC News the best time to get a newly updated COVID-19 booster is "no later than the end of October for maximum protection," which aligns with flu shot timing recommendations.

The "Goldilocks moment" for the flu shot is also October, said Dr. Peter Chin-Hong, an infectious disease specialist at the University of California, San Francisco. However, anyone who gets the shot in September should still expect protection during the flu season, which typically lasts until spring.

"I think my general advice is, get it [when] it's convenient," Chin-Hong said.

Experts also say not to worry if you can't get your flu shot before Halloween.

"If you for whatever reason cannot get a flu shot by the end of October, it's not too late," said Dr. Alok Patel, a pediatrician at Stanford Children's Health and an ABC News medical contributor.

Bad flu season on the horizon?

Some experts predict that the seasonal influenza virus -- following two years of mild activity during the COVID-19 pandemic -- is expected to be back in full force this season.

A typical pre-pandemic year would see around 8% of the U.S. population sick from flu, according to the Centers for Disease Control and Prevention. Deaths can exceed more than 50,000, as they did most recently in the 2017-2018 season.

Those most at risk of severe illness from influenza are the elderly and immunocompromised.

"What we're concerned about, of course, are people who are older, over age 65. They account for about 15-17% of the population but 80% of the [flu] deaths and hospitalizations," said Dr. William Schaffner, a professor of infectious diseases at Vanderbilt University Medical Center.

But even young, otherwise healthy people benefit from the flu shot, which also lowers the risk of spreading the virus to others.

"A lower risk does not mean no risk. By getting vaccinated, you really do reduce the likelihood that you will be the dreaded spreader," Schaffner said.

Meanwhile, becoming ill with the flu can not only put a damper on holiday plans, but it also often leads to unwanted symptoms that last for multiple days.

"For anybody who's gotten the flu, it's definitely not a walk in the park," Chin-Hong said.

Getting vaccinated in October or early November is ideal because "[you want] your annual vaccination to extend throughout the winter, well through February into March, and even into April," Schaffner said.

"The only other sort of change with the timing might be for people who are pregnant," Chin-Hong said. He explained that pregnant women may want to try and have a flu shot before delivery, which allows the newborn to benefit from the mother's antibodies, especially given that infants under 6 months old cannot be vaccinated.

Experts say flu shots may be especially important for children this year given concerns about how the relaxation of pandemic-era restrictions may impact children.

"Given the fact that schools are back open, COVID-19 restrictions have been lifted, and kids are back to their normal rambunctious selves [they] are at risk of catching influenza this year," Patel said. "Parents should not generalize influenza as a common cold. Thousands of kids are hospitalized every year from influenza with young infants and kids with underlying medical conditions being at highest risk."

Updated COVID-19 boosters may also become annual shots

The Food and Drug Administration recently authorized the first updated COVID-19 booster shots -- the first major upgrade to COVID-19 vaccines. Because protection from COVID-19 fades slowly over time, the White House has previously stated that variant-specific COVID shots may also become an annual reality, similar to seasonal flu shots.

The new COVID-19 boosters are designed to be a better match against currently circulating COVID-19 variants, and are currently authorized for everyone 12 and older who had their last COVID-19 shot at least two months ago. People previously infected with COVID may also consider waiting 90 days before receiving their booster shot, according to the CDC. The authorization of updated boosters for younger children is expected in "a matter of weeks," according to Dr. Peter Marks, the director of the group within the FDA responsible for assuring the safety and efficacy of vaccines.

Although it is not clear if there will be another COVID-19 surge this fall, more than 350 people still die every day of COVID-19. Compared to young adults, those over the age of 65 are 60 times more likely to die from COVID-19, according to the CDC. The death rate is 340 times higher for those over the age of 85.

Is it safe to get the COVID booster and flu shot at the same time?

Experts say that getting both your COVID booster and flu shot at the same time won't weaken your body's immune capacity to fight either virus.

"If you give the body two signals, it's not going to make less [immunity] because it's concentrating on another signal," Chin-Hong said.

Although children under 12 are not yet eligible for the new booster shots, many are still getting their original COVID-19 vaccines, which are authorized for children 6 months and older.

Similar to the guidance for adults, pediatricians say it's safe to give young children COVID-19 shots and flu shots in the same doctor's visit.

"This may even be a more convenient option for busy parents," Patel added.

Youri Benadjaoud is an MPH candidate at Brown University and a member of the ABC News Medical Unit.