Wondering when to get your flu shot? The best time is before influenza (flu) starts circulating widely. For most people, September or October is ideal for protection through the whole flu season, as the immune response from the vaccine wanes over time. And while changes and restrictions due to COVID-19 may make getting a flu vaccine less convenient for some this year, the pandemic makes it more important than ever.
Why do I need to get a flu vaccine yearly?
Influenza A and Influenza B cause most cases of flu in humans. Both have many strains that constantly change, accumulating genetic mutations that disguise them from the immune system. Prior exposure to one strain of flu will not necessarily protect you from other strains. Your immune system might not even recognize the same strain if it has mutated enough.
The Centers for Disease Control and Prevention (CDC) constantly monitor changing strains of influenza around the world. They use this data to develop vaccines months before flu season starts to protect against the most likely strains to reach the US. This flu season, common strains are likely to include H1N1 and H3N2.
How effective is the flu vaccine?
Although the vaccine is not perfect, it is 40% to 60% effective in most years. And if you do get the flu it is likely to be milder, because vaccination reduces the risk of severe illness or death.
During the 2018–2019 flu season, 35.5 million Americans got sick with the flu, and 34,200 died from the flu. However, last year half of all Americans received the flu shot. The CDC estimates this prevented 4.4 million cases of flu, 58,000 hospitalizations, and 3,500 deaths. That’s equivalent to saving 10 lives per day during flu season. The flu vaccine has additional benefits for people with chronic medical conditions, like reducing the risk of heart attacks, strokes, or death among people with heart disease, and decreasing illness flares in people with chronic obstructive pulmonary disease (COPD).
Why is it especially important to get the flu vaccine this year?
Measures that help protect us against COVID-19 — such as distancing, wearing face coverings, and washing hands often — may also decrease the spread of flu. Yet it’s more important than ever to get vaccinated. The COVID-19 pandemic has caused shortages of hospital beds, ICU beds, and ventilators even outside of flu season. During flu season, when both the flu and COVID-19 will be circulating, hospitals may again face shortages, limiting their ability to care for people who are seriously ill with the flu, COVID-19, or both.
People can get COVID-19 and the flu at the same time. A recent study showed people who had COVID-19 and influenza B were sicker than those who had COVID-19 alone.
Also, COVID-19 and flu have similar symptoms like fever, chills, fatigue, body aches, and coughs. So people who get the flu may need to be tested for COVID-19, and then quarantine until they get the test result. This could mean more days out of work. It could also lead to testing shortages.
Which type of flu vaccine should I get?
The CDC recommends a vaccine for everyone 6 months or older, with very few exceptions. Which flu vaccine is right for you depends on factors like age, allergies, coexisting illnesses, and vaccine availability. For adults who have no allergies or chronic medical conditions, and who are not pregnant, the CDC does not recommend any one vaccine over another.
- Eleven flu vaccines are approved by the FDA for the 2020–2021 season. Most are available as shots, and contain either inactivated (killed) virus or recombinant virus (made using lab techniques). Vaccines can be made using egg-based or non-egg-based processes.
- A trivalent (three-part) flu vaccine contains two strains of influenza A (one H1N1 and one H3N2) and one of Influenza B.
- A quadrivalent (four-part) vaccine adds another Influenza B strain.
- A vaccine given as a nasal spray is quadrivalent, and contains live attenuated (weakened) virus. It’s approved for healthy, non-pregnant people ages 2 to 49.
- A high-dose flu vaccine and a flu vaccine with an adjuvant (an ingredient which boosts immune response) offer additional protection to people ages 65 and older. These are not approved for younger people.
Infants under 6 months are too young to be vaccinated, but if their mother received a flu vaccine while pregnant, babies have partial protection after birth. People who have had severe, life-threatening allergies to the influenza vaccine or any of its ingredients should not be vaccinated. However, most people with egg allergies can get the flu shot. Depending on their reaction to eggs, they can either get the same vaccines as someone without allergies or get an egg-free flu vaccine. If you have an egg allergy, any history of allergies to vaccines or components of the flu vaccine, or if you have had Guillain-Barré syndrome (a rare condition where the immune system attacks the nerves), talk to your doctor before getting vaccinated.
Where can I get a flu vaccine?
You can check with your doctor or health plan to find local flu vaccine clinics. Vaccines are also available at drug stores, supermarkets, and health clinics. Depending on insurance, the flu vaccine may be free.
You can also check with your local board of health for free vaccine sites. In many cities and states, you can call 211 for this information.
The CDC emphasizes how important it is for as many people as possible to get the flu vaccine this year, and issued guidelines for minimizing COVID-19 risks while doing so. Healthcare facilities are taking measures to reduce risk, such as symptom screening, spacing of appointments, and enforcing social distancing and mask-wearing. With appropriate precautions, COVID-19 exposure risk while getting your flu vaccine should be minimal, no greater than going to the store.
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