Flu vaccine

Flu vaccine
Other names	Influenza vaccine
Specialty	Immunology, Virology

The flu vaccine, also known as the influenza vaccine, is a vaccine designed to protect against the influenza virus. Each year, the vaccine is formulated to guard against the influenza viruses that research indicates will be most common during the upcoming season. The main types of influenza vaccines include the inactivated influenza vaccine (IIV) and the live attenuated influenza vaccine (LAIV).

Types of Flu Vaccines

There are several types of flu vaccines available:

• Inactivated Influenza Vaccine (IIV): Administered via injection, this vaccine contains killed virus and is used in people aged 6 months and older.
• Live Attenuated Influenza Vaccine (LAIV): This type is a nasal spray and contains a weakened form of the virus. It is approved for use in individuals aged 2 through 49 years who are not pregnant and do not have weakened immune systems.
• Recombinant Influenza Vaccine (RIV): This is a newer type of flu vaccine that does not use the influenza virus or eggs in its production.

Effectiveness

The effectiveness of the flu vaccine can vary. The vaccine is typically more effective among healthy adults and older children. Some older people and people with certain chronic illnesses might develop less immunity after receiving a flu shot. The effectiveness of the flu vaccine also depends on the similarity or "match" between the viruses used to produce the vaccine and those circulating in the community.

Recommendations

The World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC) recommend annual vaccination for nearly all people over the age of six months, especially those at high risk of serious flu complications, such as young children, elderly adults, pregnant women, and individuals with chronic health conditions.

Side Effects

Common side effects of the flu vaccine include soreness at the injection site, low-grade fever, and muscle aches. The nasal spray vaccine may cause additional symptoms such as runny nose, headache, and sore throat.

History

The development of the flu vaccine began in the 1930s, with the first inactivated influenza vaccine being licensed in America in 1945. Since then, flu vaccines have been a key component in controlling the spread of influenza globally.

See Also

• Vaccine
• Epidemiology of influenza
• Herd immunity
• Pandemic