Influenza vaccine

Influenza vaccine
A flu shot being given to a US Navy crew member
Vaccine description
TargetInfluenza virus
Vaccine typeinactivated, attenuated, recombinant
Clinical data
Trade namesAfluria, Fluarix, Fluzone, others
AHFS/Drugs.comInactivated: Monograph Intranasal: Monograph Recombinant: Monograph
Pregnancy
category
  • AU: B1or B2 (depending on vaccine brand)[1][2][3]
Routes of
administration
Intramuscular, intranasal, intradermal
ATC code
Legal status
Legal status
Identifiers
CAS Number
ChemSpider
  • none
KEGG

Influenza vaccines, colloquially known as flu shots[14] or the flu jab,[15] are vaccines that protect against infection by influenza viruses.[16][17] New versions of the vaccines are developed twice a year, as the influenza virus rapidly changes.[16] While their effectiveness varies from year to year, most provide modest to high protection against influenza.[16][18] Vaccination against influenza began in the 1930s, with large-scale availability in the United States beginning in 1945.[19][20]

Both the World Health Organization and the US Centers for Disease Control and Prevention (CDC) recommend yearly vaccination for nearly all people over the age of six months, especially those at high risk,[16][21][22][23] and the influenza vaccine is on the World Health Organization's List of Essential Medicines.[24] The European Centre for Disease Prevention and Control (ECDC) also recommends yearly vaccination of high-risk groups,[25] particularly pregnant women, the elderly, children between six months and five years, and those with certain health problems.[16][23]

The vaccines are generally safe, including for people who have severe egg allergies.[26] A common side effect is soreness near the site of injection. Fever occurs in five to ten percent of children vaccinated, and temporary muscle pains or feelings of tiredness may occur. In certain years, the vaccine was linked to an increase in Guillain–Barré syndrome among older people at a rate of about one case per million doses.[16] Influenza vaccines are not recommended in those who have had a severe allergy to previous versions of the vaccine itself.[16][26] The vaccine comes in inactive and weakened viral forms. The live, weakened vaccine is generally not recommended in pregnant women, children less than two years old, adults older than 50, or people with a weakened immune system.[16] Depending on the type it can be injected into a muscle (intramuscular), sprayed into the nose (intranasal), or injected into the middle layer of the skin (intradermal).[16] The intradermal vaccine was not available during the 2018–2019 and 2019–2020 influenza seasons.[27][28][29]

  1. ^ a b "AusPAR: Influenza Haemagglutinin Recombinant". Therapeutic Goods Administration (TGA). August 23, 2021. Archived from the original on September 11, 2021. Retrieved September 10, 2021.
  2. ^ a b "AusPAR: Inactivated quadrivalent influenza vaccine (split virion) influenza virus haemagglutinin". Therapeutic Goods Administration (TGA). December 2, 2020. Archived from the original on September 11, 2021. Retrieved September 10, 2021.
  3. ^ "Updates to the Prescribing Medicines in Pregnancy database". Therapeutic Goods Administration (TGA). December 21, 2022. Archived from the original on April 3, 2022. Retrieved January 2, 2023.
  4. ^ "Prescription medicines: registration of new chemical entities in Australia, 2017". Therapeutic Goods Administration (TGA). June 21, 2022. Archived from the original on April 10, 2023. Retrieved April 9, 2023.
  5. ^ "Prescription medicines: registration of new chemical entities in Australia, 2016". Therapeutic Goods Administration (TGA). June 21, 2022. Archived from the original on April 10, 2023. Retrieved April 10, 2023.
  6. ^ https://www.tga.gov.au/resources/auspar/auspar-flucelvax-quad-0 [bare URL]
  7. ^ "Summary Basis of Decision (SBD) for Supemtek". Health Canada. October 23, 2014. Archived from the original on May 30, 2022. Retrieved May 29, 2022.
  8. ^ "Regulatory Decision Summary - Flucelvax Quad". Health Canada. October 23, 2014. Archived from the original on June 7, 2022. Retrieved June 7, 2022.
  9. ^ "Regulatory Decision Summary - Flucelvax Quad". Health Canada. October 23, 2014. Archived from the original on June 7, 2022. Retrieved June 7, 2022.
  10. ^ "Regulatory Decision Summary - Influvac Tetra". Health Canada. October 23, 2014. Archived from the original on June 7, 2022. Retrieved June 7, 2022.
  11. ^ "Regulatory Decision Summary for Panenza (Haemagglutinin-Strain A (H1N1))". Drug and Health Products Portal. October 27, 2023. Retrieved April 2, 2024.
  12. ^ "Supemtek EPAR". European Medicines Agency. November 25, 2020. Retrieved June 27, 2024.
  13. ^ "Fluad Tetra". European Medicines Agency (EMA). May 20, 2020. Retrieved August 10, 2024.
  14. ^ "Key Facts About Seasonal Flu Vaccine". Influenza (Flu). September 30, 2024.
  15. ^ "The flu jab in pregnancy". nhs.uk. December 3, 2020.
  16. ^ a b c d e f g h i World Health Organization (November 2012). "Vaccines against influenza WHO position paper". Weekly Epidemiological Record. 87 (47): 461–76. hdl:10665/241993. PMID 23210147.
  17. ^ World Health Organization (May 2022). "Vaccines against influenza: WHO position paper – May 2022". Weekly Epidemiological Record. 97 (19): 185–208. hdl:10665/354265.
  18. ^ Manzoli L, Ioannidis JP, Flacco ME, De Vito C, Villari P (July 2012). "Effectiveness and harms of seasonal and pandemic influenza vaccines in children, adults and elderly: a critical review and re-analysis of 15 meta-analyses". Human Vaccines & Immunotherapeutics. 8 (7): 851–62. doi:10.4161/hv.19917. PMC 3495721. PMID 22777099.
  19. ^ Compans RW (2009). Vaccines for pandemic influenza. Dordrecht: Springer. p. 49. ISBN 978-3-540-92165-3. Archived from the original on August 3, 2020. Retrieved September 9, 2017.
  20. ^ Vaccine Analysis: Strategies, Principles, and Control. Springer. 2014. p. 61. ISBN 978-3-662-45024-6. Archived from the original on August 3, 2020. Retrieved September 9, 2017.
  21. ^ "Who Should and Who Should NOT get a Flu Vaccine". U.S. Centers for Disease Control and Prevention (CDC). October 11, 2019. Archived from the original on December 2, 2019. Retrieved December 2, 2019. Public Domain This article incorporates text from this source, which is in the public domain.
  22. ^ The immunological basis for immunization series: module 23: influenza vaccines. World Health Organization (WHO). October 2017. hdl:10665/259211. ISBN 978-92-4-151305-0.
  23. ^ a b Cite error: The named reference pmid34448800 was invoked but never defined (see the help page).
  24. ^ World Health Organization (2023). The selection and use of essential medicines 2023: web annex A: World Health Organization model list of essential medicines: 23rd list (2023). Geneva: World Health Organization. hdl:10665/371090. WHO/MHP/HPS/EML/2023.02.
  25. ^ "Implementation of the Council Recommendation on seasonal influenza vaccination (2009/1019/EU)" (PDF). European Centre for Disease Prevention and Control. January 2014. Archived (PDF) from the original on April 10, 2020. Retrieved April 10, 2020.
  26. ^ a b "Flu Vaccine and People with Egg Allergies". U.S. Centers for Disease Control and Prevention (CDC). November 25, 2019. Archived from the original on December 2, 2019. Retrieved December 2, 2019. Public Domain This article incorporates text from this source, which is in the public domain.
  27. ^ "Intradermal Influenza (Flu) Vaccination". U.S. Centers for Disease Control and Prevention (CDC). October 31, 2018. Archived from the original on October 14, 2019. Retrieved October 14, 2019. Public Domain This article incorporates text from this source, which is in the public domain.
  28. ^ "Influenza vaccines – United States, 2019–20 influenza season". U.S. Centers for Disease Control and Prevention (CDC). August 22, 2019. Archived from the original on October 14, 2019. Retrieved October 14, 2019. Public Domain This article incorporates text from this source, which is in the public domain.
  29. ^ "Influenza Virus Vaccine Inactivated". The American Society of Health-System Pharmacists. November 19, 2018. Archived from the original on October 14, 2019. Retrieved October 13, 2019.