The 2017-2018 flu season was a bad one. The dominant viral strain, H3N2, was a particularly severe form of influenza, leading to widespread and serious illness across the country. The flu and its complications killed around 80,000 people last year, the CDC estimates, including 180 children. That’s the highest flu death toll in four decades.
Experts say early indications suggest that this year’s flu season will be milder, but deaths have already been reported, including a child in Florida and an older adult in Connecticut. Those cases, along with the memory of last year, should serve as motivation to get a flu shot. Here’s what you need to know about the 2018 flu shot, including its effectiveness and potential symptoms.
When should I get the flu shot?
The CDC recommends getting your flu shot by the end of October, before the bulk of the 2018-2019 flu season hits, because it takes about two weeks for the flu shot to take effect. But don’t give up if you miss that window — you can still get a flu shot well into the fall or winter, says Dr. Tanaya Bhowmick, an assistant professor of medicine and infectious diseases at Rutgers’ Robert Wood Johnson Medical School. “It’s never too late to get the flu vaccine,” Bhowmick says.
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How effective is the flu shot?
The formulation of the flu shot is tweaked every year, in an effort to target the specific strains of influenza that are likely to circulate during that flu season. But without knowing exactly which strains will get people sick, it’s impossible to predict exactly how effective it will be in any given year.
During the brutal 2017-2018 flu season, the CDC said the vaccine was only about 36% effective, with particularly low efficacy against the H3N2 strain. Nonetheless, the CDC stresses that even small increases in immunity can make a big difference, both on an individual and a population level. If fewer people get sick, there’s fewer flu virus to be spread, and the ripple effect continues. Plus, vaccinated people who end up getting sick tend to have less severe illnesses, Bhowmick says. “Maybe you’re not in bed for a week,” she says. “Maybe it’s only two, three, four days, and it’s not going to be as severe as if you had the actual flu.”
Flu shots also tend to be more effective for children — and since kids, along with the elderly, are susceptible to complications of the disease, it’s especially important that they get vaccinated.
Which flu shot is best?
While certain shots are approved for specific age ranges (you can talk to your doctor about which is the best fit for you) the CDC does not recommend any version of the shot over any other. “The most important thing,” the agency says, “is for all people six months and older to get a flu vaccine every year.”
You may, however, have an extra choice this flu season. The CDC is once again recommending the inhaled flu vaccine, the nasal spray FluMist, as an alternative to traditional shots this year, after efficacy problems kept it out of doctors’ offices for the past two years. The nasal spray flu vaccine formulation has been adjusted to address those issues, leading the CDC to return it to the list of recommended options. (Bhowmick says she personally prefers the traditional vaccine, though the nasal spray could be a good option for the needle-averse who otherwise wouldn’t get vaccinated.)
Where can you get the flu shot for free?
Many physicians and employers offer free flu shots, and a number of national retail chains are also offering the 2018 flu vaccine for free. Under most health insurance plans, you can get a free flu shot at chains including Walgreens, CVS (including many in Target stores), Publix, Costco, Walmart and Rite Aid. Some places, including Publix and CVS, even offer store discounts if you get a flu shot. If you choose to pay out-of-pocket, the flu shot typically costs $40 or less at locations like these.
Will the flu shot cause any side effects or symptoms?
Flu vaccines are made with inactivated or weakened versions of the influenza virus, so they help the body produce illness-fighting antibodies, but do not cause infection. You won’t get a full-blown bout of the flu after getting vaccinated, but you may experience mild versions of symptoms associated with the flu as your body builds its immune response. Flu shot side effects can include pain or redness in the arm where you got the shot, body aches and a low-grade fever, the CDC says. If you get the nasal spray, you may experience a runny nose, headache, sore throat or cough.
Don’t be concerned if you see these symptoms, Bhowmick says. “It gives you an idea that the vaccine is actually working,” she says. “So it’s not necessarily a bad thing that you might feel that way.”
Who shouldn’t get the flu shot?
With very few exceptions, the CDC recommends the flu shot to everyone older than six months, including pregnant women and people with chronic health conditions.
If you’re severely allergic to the flu shot or any of its components, you should not get vaccinated, the CDC says. People with egg allergies, however, can still get the flu shot, even though eggs are involved in the manufacturing process; tell your doctor if you have severe allergies and are concerned about getting the shot. Consult your doctor before getting a flu shot if you’ve ever had the immune disorder Guillain-Barré Syndrome.
If you’re sick on the day you planned to get your flu shot, you may want to hold off, Bhowmick says. Getting the shot while you have a cold or minor illness won’t do any harm, but “if you have a fever, if you just got sick and you’re coughing and sneezing, it’s probably not the best time to get it,” Bhowmick says, since the side effects could compound your symptoms. Just make sure you go back when you’re feeling better.