Live attenuated influenza vaccine (LAIV) is a type of influenza vaccine in the form of a nasal spray that is recommended for the prevention of influenza.[2][7]
It is an attenuated live vaccine, unlike other influenza vaccines, which are inactivated vaccines. Live attenuated influenza vaccine is administered intranasally,[8] while inactivated vaccines are administered by intramuscular injection. Live attenuated influenza vaccine is sold under the brand names FluMist and FluMist Quadrivalent in the United States; and the brand name Fluenz Tetra in the European Union.[4][6] FluMist was first introduced in 2003 by MedImmune.[9][10][11]
In the United States, FluMist is approved for self- or caregiver-administration.[12][13] It is the first influenza vaccine that does not need to be administered by a health care provider.[12]
^Block SL, Yogev R, Hayden FG, Ambrose CS, Zeng W, Walker RE (September 2008). "Shedding and immunogenicity of live attenuated influenza vaccine virus in subjects 5-49 years of age". Vaccine. 26 (38): 4940–4946. doi:10.1016/j.vaccine.2008.07.013. PMID18662737.