The flu shot prompts your immune system to produce antibodies against a specific strain of the flu. If you’re exposed to this particular flu virus later, you’ll already have antibodies ready to fight off the virus.

It usually takes about 2 weeks to build up your immunity to a flu virus after you’ve been vaccinated against it.

You’ll have the most antibodies 1 to 2 months later. After this time, your protection begins to decline. That’s why you need a flu shot every year.

Each year’s vaccine is based on which strains are most likely to spread during that flu season.

The vaccine won’t protect you from every strain. But if you do get sick, it’ll likely be less severe due to the vaccine.

The 2020-21 flu season may be complicated by the COVID-19 pandemic. The overlap of these two viral illnesses threatens to overburden hospitals, which typically get an influx of patients who have complications from the seasonal flu.

Getting your flu shot can help lower your risk of flu complications that could put you in the hospital.