FluMist vaccine: Questions and Answers

Jane McDonald, Dorothy Moore; Canadian Paediatric Society, Infectious Diseases and Immunization Committee

Index of position statements from the Infectious Diseases and Immunization Committee

Contents

• What is FluMist?
• Who is FluMist licensed for in Canada?
• How well does it work compared with inactivated influenza vaccine in children?
• Who may be given LAIV?
• Who should NOT be given LAIV?
• What are the side effects of FluMist?
• How is the vaccine stored?
• How is the vaccine given?
• How many doses are required?
• Does the nasal spray contain any preservatives?
• Are there interactions with other vaccines?
• Can patients on antivirals receive FluMist?
• Where is FluMist available? Who pays for it?  What does it cost?
• Additional resources

What is FluMist?
FluMist (AstraZeneca Canada Inc.) is a vaccine containing live, attenuated cold-adapted influenza strains for intranasal administration (also referred to as live attenuated influenza vaccine or LAIV). The vaccine for 2010–11 contains A/California/7/2009 (H1N1), A/Perth/16/2009 (H3N2) and B/Brisbane/60/2008. The attenuated vaccine viruses replicate in the nasopharynx and induce protective immunity. The vaccine strains are produced in eggs and then partially purified. The final preparation contains monosodium glutamate, gelatin, arginine, sucrose, dibasic potassium phosphate, monobasic potassium phosphate, and gentamicin. FluMist does not contain thimerosal or other preservatives.

Who is FluMist licensed for in Canada?
Persons aged 2 to 59 years.

How well does it work compared with inactivated influenza vaccine in children?
The efficacy of LAIV has been looked at in a number of studies in paediatrics. It was found to be about 86% to 96% efficacious against virologically confirmed influenza A (H3N2) in one study. Similar studies have shown the killed vaccine to be anywhere from 70% to 80% efficacious (depending on the match of the vaccine components to the circulating strains during the influenza season). It seems that the LAIV may be more efficacious in preventing influenza in children than the inactivated influenza vaccine, but more studies covering more seasons are needed to determine this.

Who may be given LAIV?
The vaccine can be given to previously healthy, non-pregnant persons between the ages of 2 and 59 years.

Who should NOT be given LAIV?

• Children under 2 years of age, because of the observation of increased risk of hospitalization and wheezing in clinical trials.
• Persons with a history of asthma. Children under 5 years old with recurrent wheezing or a wheezing episode in the previous 12 months should not receive vaccine as they may have asthma. This vaccine may cause bronchospasm so should not be given to persons who are actively wheezing.
• Persons with underlying chronic medical conditions that confer higher risk of influenza complications (eg., chronic heart or lung disease). 
• Persons receiving aspirin or other salicylates.
• Persons with a known or suspected immunodeficiency or persons receiving immunosuppressive therapy.
• Close contacts of a person who is severely immunocompromised, as the vaccine virus may be shed. If given anyway, restrict contact with the immunocompromised person for 7 days after vaccination.
• Pregnant women, as this vaccine has not been studied in pregnancy.
• Anyone with known allergic reactions (hives, angioedema, allergic asthma, systemic anaphylaxis) to eggs or chicken, to any previous influenza vaccine dose, or to any of the components of LAIV. Less severe manifestations of allergy are not contraindications.
• People who had Guillain-Barré Syndrome within 6 weeks after a previous influenza vaccination.
• People with nasal congestion, if the amount of congestion is anticipated to impede the delivery of the vaccine to the nasopharyngeal mucosa. Vaccine can be given once the congestion is resolved.

What are the side effects of FluMist?
LAIV has the potential to cause mild signs related to attenuated influenza virus infection. The most common side effects are runny nose or nasal congestion, sore throat and fever.

How is the vaccine stored?
FluMist is shipped refrigerated and must be stored in a refrigerator at 2 to 8°C.  It should not be frozen.

How is the vaccine given?
It is administered by intranasal spray, with the dose divided equally between the two nostrils. It is provided in a prefilled single use sprayer containing 0.2 ml of vaccine. A dose-divider clip allows administration of 0.1 ml into each nostril.

How many doses are required?
LAIV is given annually in 1 or 2 doses, depending on age (each dose is one squirt into each nostril). Children under 9 years of age who have received one or more doses of trivalent influenza vaccine in the past should receive 1 dose of the LAIV.  Children under 9 years of age who have not previously received a dose of influenza vaccine in a previous season should receive two doses at least 4 weeks apart.

Does the nasal spray contain any preservatives?
No, it does not contain thimerosal or any other preservative.

Are there interactions with other vaccines?
LAIV can be given simultaneously with other live vaccines (eg., MMR, MMRV, or other live vaccines). If it is not given at the same time, there should be a gap of 4 weeks between doses of LAIV and another live vaccine. LAIV can be administered with killed vaccines regardless of the time interval between vaccines.

Can patients on antivirals receive FluMist?
LAIV should not be given to anyone who is currently taking an antiviral drug against influenza virus.

Where is FluMist available? Who pays for it?  What does it cost?
FluMist is not currently available through the publicly funded provincial and territorial influenza vaccine programs.  Nevertheless, some parents may prefer to purchase this to avoid an injection for their child.  It may be available at a pharmacy.

ADDITIONAL RESOURCES:
http://aapredbook.aappublications.org/news/FluPolicy2009-10.pdf (Accessed December 3, 2010)

http://www.cdc.gov/vaccines/pubs/vis/downloads/vis-flulive.pdf  (Accessed December 3, 2010)

http://www.astrazeneca.ca/documents/ProductPortfolio/FLUMIST_PM_en.pdf

INFECTIOUS DISEASES AND IMMUNIZATION COMMITTEE
Members: Drs Robert Bortolussi, IWK Health Centre, Halifax, Nova Scotia (Chair); Jane Finlay, Richmond, British Columbia; Susanna Martin, Royal University Hospital, Saskatoon, Saskatchewan (Board Representative); Jane McDonald, The Montreal Children’s Hospital, Montreal, Quebec; Heather Onyett, Queen’s University, Kingston, Ontario; Joan Robinson, Edmonton, Alberta
Liaisons: Drs Upton Allen, The Hospital for Sick Children, Toronto, Ontario (Canadian Pediatric AIDS Research Group); Janet Dollin, University of Ottawa, Ottawa, Ontario (College of Family Physicians of Canada); Charles Hui, Children’s Hospital of Eastern Ontario, Ottawa, Ontario (CPS Liaison to Health Canada, Committee to Advise on Tropical Medicine and Travel); Nicole Le Saux, Children’s Hospital of Eastern Ontario, Ottawa, Ontario (Canadian Immunization Monitoring Program, ACTive); Larry Pickering, Elk Grove, Illinois (American Academy of Pediatrics, Committee on Infectious Diseases); Marina Salvadori, Children’s Hospital of Western Ontario, London, Ontario (CPS Liaison to Health Canada, National Advisory Committee on Immunization), John Spika, Ottawa, Ontario (Public Health Agency of Canada)
Consultants: Drs James Kellner, Alberta Children’s Hospital, Calgary, Alberta; Noni MacDonald, IWK Health Centre, Halifax, Nova Scotia; Dorothy Moore, The Montreal Children’s Hospital, Montreal, Quebec
Principal authors: Drs Jane McDonald, Montreal, Quebec; Dorothy Moore, Montreal, Quebec

Posted: December 2010