What is the flu shot?
The flu shot is a vaccine given with a needle, usually in the arm. The seasonal flu vaccine protects against the three or four influenza viruses that research indicates will be most common during the upcoming season.
There are several flu vaccine options for the 2013-2014 flu season.
Traditional flu vaccines made to protect against three different flu viruses (called “trivalent” vaccines) are available. In addition, this season flu vaccines made to protect against four different flu viruses (called “quadrivalent” vaccines) also are available.
The trivalent flu vaccine protects against two influenza A viruses and an influenza B virus. The following trivalent flu vaccines are available:
- Standard dose trivalent shots that are manufactured using virus grown in eggs. These are approved for people ages 6 months and older. There are different brands of this type of vaccine, and each is approved for different ages. However, there is a brand that is approved for children as young as 6 months old and up.
- A standard dose trivalent shot containing virus grown in cell culture, which is approved for people 18 and older.
- A standard dose trivalent shot that is egg-free, approved for people 18 through 49 years of age.
- A high-dose trivalent shot, approved for people 65 and older.
- A standard dose intradermal trivalent shot, which is injected into the skin instead of the muscle and uses a much smaller needle than the regular flu shot, approved for people 18 through 64 years of age.
The quadrivalent flu vaccine protects against two influenza A viruses and two influenza B viruses. The following quadrivalent flu vaccines are available:
- A standard dose quadrivalent shot
- A standard dose quadrivalent flu vaccine, given as a nasal spray, approved for healthy* people 2 through 49 years of age
(*”Healthy” indicates persons who do not have an underlying medical condition that predisposes them to influenza complications.)