Flu Shot 2021: Should You Get One?

Last year we experienced a record-low flu season, at least partly due to limited indoor gatherings and continued hand-washing and mask use. That proved to be a relief to scientists who warned of hospitals overflowing with both COVID-19 and influenza patients to the point where healthcare professionals wouldn’t have the resources to properly care for either group.

“The big concern is that we are going to see what could be a perfect storm of accelerated COVID-19 activity, as more people gather inside … become fatigued with social distancing, mask-wearing and hand hygiene and then are exposed to seasonal influenza,” Jeanne Marrazzo, MD, director of the division of infectious diseases at the University of Alabama, Birmingham, said at a Sept. 10, 2020 media briefing sponsored by the Infectious Diseases Society of America.

While the “perfect storm” Marrazzo warned about didn’t happen in 2020-2021, there’s more reason to be cautious for the 2021-2022 season. “The flu this year could be more severe for a few reasons. First, there were only about 3000 cases last year so there wasn’t much exposure for natural immunity to occur,” says Peter Gulick, MD, an associate professor of medicine at Michigan State University. He adds that thanks to COVID-19 vaccination, fewer people are taking precautions like wearing masks and social distancing this year, which “will contribute to a more serious flu season. We’re also seeing more RSV [respiratory syncytial virus], adenovirus and parainfluenza already, which may be a predictor for the flu season.” He encourages flu shots for everyone who can get them.

Keep Up to Date on Influenza Spread

The Centers for Disease Control post weekly updates on the spread of the flu throughout the season. You can find the weekly FluView updates here. While circulation is low as of late October 2021, the CDC says you should not wait until there are more cases to get the shot. The best time to get vaccinated is now. “Everyone she be vaccinated by the end of October,” the website states.

Last year, the organization states that cases of influenza remained low “despite high levels of testing,” suggesting that it was unlikely the low caseload was due to doctors mistaking flu for COVID-19. The CDC agrees with Gulick that social distancing and mask-wearing played a role in low numbers of influenza cases last year, but the agency adds that a record-high number of people in the U.S. received their flu vaccines during the 2020-2021 season, which also likely played a role in minimizing harm.

Benefits of the Flu Vaccine

Even though the flu shot is not a perfect vaccine and offers only 40% to 60% protection from infection, it can provide enormous benefits. 

Scientists say that that’s enough to minimize the disease’s spread throughout the population. If you do contract the disease, having had the vaccination may render any flu you do contract less severe, preventing the most serious complications, like pneumonia and even death. In 2019, between 24,000 and 62,000 Americans died from the flu and between 410,000 and 740,000 were hospitalized because of it. Flu is rarely listed as cause of death on death certificates. Instead, the cause is more often called pneumonia or another affliction the flu can lead to. 

What’s In a Flu Vaccine

To come up with a new flu vaccine each year, researchers make educated guesses as to which strains of flu are most likely to cause the illness based on what circulated the previous year.  

“They can never know exactly which strains are going to happen. Each flu shot that we get has at least three or four strains of flu from the preceding season,” says Daren Wu, MD, chief medical officer at Open Door Family Medical Center in New York City.

The main ingredients in influenza vaccines are either dead or weakened flu viruses. These viruses cannot replicate and wreak havoc on your body like a normal flu virus, but their purpose is to prompt your immune system to mount an immune response. This response prepares your body to recognize and respond faster if it does encounter the actual influenza virus later in the season. 

The Vaccine’s Possible Side Effects

The flu vaccine can cause side effects, which, while not generally not dangerous, can mimic the types of symptoms you might get from a mild influenza infection. “Once in a while, people have very uncomfortable reactions. Your body aches, [you can experience] chills, headaches. I’ve had those at least twice in the last 20 years of getting flu shots since I became a doctor. And I felt terrible,” says Wu.

It is concerns about side effects that a third of parents cited as the reason for not having their children receive the flu vaccine, according to a survey.

“In the process of mounting that immune response, making the antibodies to be able to battle the real flu, people can feel terrible because it feels like you’re fighting off the flu” Wu says. He adds, “It’s a one, two-day reaction that’s completely different from actually getting the flu, which is a seven-day or more process. One is an immune reaction that is temporary, and the other is you are infected.” 

Aside from brief, flu-like symptoms lasting a day or two, patients also report pain or soreness at the injection site. Wu says this reaction is common. He recommends  keeping the arm moving to alleviate the pain. If the pain is acute, Wu suggests you taking Tylenol, Advil or Motrin. He cautions, however, that you should only do so if you feel very sick, because it can interfere with the immune system response to the flu shot, which lowers the effectiveness of the flu shot. 

Lastly, there are some other possible side effects, depending on the type of vaccine you get. Most vaccines do not not contain thimerosal, a preservative that was once considered controversial, but has since been shown to be safe in vaccines. It does, however, contain egg, which can be a problem for patients with severe egg allergies. 

If you or your child has such an allergy, know that most doctors and pharmacists stock a few eggless vaccines, says Wu. These vaccines, known as cell culture vaccines, are made using animal cells and recombinant vaccines that are synthetic and don’t have egg products.

Seniors should get the higher-dose vaccines, which were designed for patients over age 65 to ensure their immune systems respond adequately.

For those who can’t tolerate needles, there are nasal spray flu vaccines. To find out where you can get your flu vaccine, check out this vaccine finder.