Q: Pharmacy signs are urging me to get a flu shot right now, but it’s still summer. Is that a good idea? I’m worried that its effectiveness will wear off when I really need it later this winter.
A: That depends on who you are. The CDC says everybody age 6 months and up should get an annual flu shot by October, which should protect them through the spring, when the virus subsides. Children 6 months through 8 years old who have never gotten the flu shot before need two doses given four weeks apart, and the CDC is recommending that they get their first vaccine in August or September so that the second dose can be given by the end of October.
But getting vaccinated in late summer, particularly for older adults, may mean less protection from the virus as flu season ramps up in January and February, the CDC warns. The shot is supposed to be effective for about six months, but several observational studies have reported decreased protection, particularly for older adults against influenza A (H3N2), as the flu season goes on.
And a flu booster shot later on is not recommended, either, because there’s not much evidence for it. That’s according to the CDC’s Aug. 25, 2017, report on the 2017-18 flu season.
What the experts say about flu vaccine
So what should you do, especially if you’re 65 and up or if you have a chronic condition like diabetes, or a compromised immune system from cancer treatment?
“Although there is no official ‘too early,’ I would not get vaccinated in August or even early September,” says William Schaffner, M.D., a professor of medicine at Vanderbilt University School of Medicine in Nashville and consultant to the CDC’s Advisory Committee on Immunization Practices.
Even if you wait until December, you will probably be protected during most flu seasons, the CDC report says. “Flu season general peaks in February for most parts of the country,” Schaffner says. “And it takes two weeks after getting the shot for protection to be maximized.”
The bottom line on flu shots
Delaying your flu shot may result in greater immunity later in the season. But putting it off may mean that you never get one, which would put you at greater risk for an illness that can knock even a healthy young person flat for weeks.
“People tend to think of influenza as an annoyance,” says John Swartzberg, MD, clinical professor of medicine emeritus at the University of California, Berkeley, School of Public Health and a specialist in infectious disease. “It’s much more than that. It puts more than 300,000 Americans in the hospital each year and kills on average 10,000 to 30,000 people.”
He says the flu shot, while not perfect, helps protect you from getting sick or makes your illness less severe if you do get the flu.
The good news is that besides being easy to find, flu shots are free under Medicare and Medicaid. If you have health insurance through work, the cost will likely be low or even free. The Affordable Care Act requires insurance companies to cover flu immunization. If you have no health insurance, the flu shot should cost $16 to $21, depending on the type you get.
Also see Flu Shot: Does Time of Day Matter?