Why do I need to get a new flu shot every year?

A flu vaccine is needed every season for two reasons:

1. The immune protection from vaccines declines over time, so an annual vaccine helps give you and your family the best protection. 
2. There are many types of flu viruses, and they are constantly changing, so flu vaccines are updated every year to protect against the viruses that research suggests may be most common in the U.S. during the upcoming flu season. For the best protection, everyone 6 months and older should get vaccinated every year.

Source:
CDC: Key Facts about Seasonal Flu Vaccine

The post Why do I need to get a new flu shot every year? appeared first on I Vaccinate.