Types of seasonal influenza vaccine

Injected trivalent inactivated influenza vaccines are most commonly used throughout the world. Influenza antigen preparation varies between manufacturers. The inactivated influenza vaccines available in the EU/EEA may contain either, split virion influenza virus products or subunit influenza products. Adjuvanted inactivated subunit influenza vaccine for older people is available in some EU/EEA Member States and is since 2015 authorised for younger children in Canada but not yet in Europe (see table below).

Injected quadrivalent inactivated influenza vaccines, available from the 2014/2015 season in some EU/EEA countries are expected to replace the trivalent vaccines over time. Although available in the private market in some European countries, vaccine authorisation, vaccine availability, observed vaccine effectiveness and the cost may influence the speed of this replacement.

In 2011, a live attenuated influenza vaccine (LAIV) for intranasal use was approved in the EU/EEA for children and adolescents (2-17 years of age). All live attenuated influenza vaccines currently available are quadrivalent combination vaccines containing two influenza A strains (H1N1 and H3N2 subtypes) and two influenza B strains (Victoria and Yamagata lineages) as per WHO recommendations.

The universal paediatric programmes organized in Finland and the United Kingdom offer quadrivalent LAIV to either young children 2-3 or 2-11 years of age, respectively.

Since seasonal influenza vaccines are usually recommended for several vulnerable populations who are poorer immune responders due to age or disease, several attempts to improve the vaccines have been explored over the last 10-15 years such as: increasing the antigen dose administered, intradermal administration to activate other arms of the immune system, and adding immunostimulating compounds such as adjuvants (1-4).

Products utilising these new techniques are now authorised and available in some EU/EEA countries. See table below. For human influenza vaccines, MF59 (squalene) and AS03 (squalene and α-tocopherol) have been approved as adjuvants by regulatory agencies in the EU, Canada and the United States. It is currently not clear if any of them perform better than the unadjuvanted vaccines although the first studies indicate better protection in the oldest age group (3, 5).

Most influenza vaccines, both inactivated and live attenuated, are based on production of influenza viruses/antigens in fertilized hens' eggs. These vaccines can therefore not be given to egg-allergic individuals developing severe symptoms upon exposure to egg proteins. Hence, a few manufacturers have developed cell-based influenza vaccines which can be given to severely egg-allergic individuals As of autumn 2017 a cell-based product is under evaluation by the European Medicines Agency for central authorisation. The vaccine produced in Hungary is a cell-based vaccine, but this vaccine is only authorised for use in Hungary.

In total, seven influenza vaccine manufacturers produce and deliver seasonal influenza vaccines to EU/EEA countries. The majority of these influenza vaccines were authorised before the creation of the European Medicines Agency in 1995 and have therefore predominantly been approved by national regulatory agencies rather than centrally approved in the EU/EEA. As a result, some influenza vaccines are named differently in different countries, despite being the exact same product. The only exception is the recently introduced intranasal live attenuated influenza vaccine which was centrally authorised by the European Medicines Agency and uses one name in the EU/EEA (Fluenz tetra), but another in the US (Flumist quadrivalent).

Overview of available seasonal influenza vaccines in the EU/EEA (2017/18 season)

To request an update of this table, please write to ECDC.Influenza@ecdc.europa.eu

Manufacturer

Name of product*

Available for use in the following countries

Vaccine type

Adjuvant

Administration route

Produced in

Age recommended

Abbot Biologicals

Trivalent:

Influvac

All EU/EEA countries

Inactivated

None

intramuscular

Egg

From 6 months

Imuvac

UK

AstraZeneca

Quadrivalent:

Fluenz tetra  

Austria, Finland, Germany, Norway, Sweden, UK

Live attenuated

None

intranasal

Egg

From 24 months to 17 years

GlaxoSmithKline

Trivalent: Fluarix** Alpharix Influsplit  

Trivalent:

All EU/EEA countries

 

Inactivated/ split

None

Trivalent intramuscular/ subcutaneous

Egg

Trivalent: From 6 months

Quadrivalent: From 3 years

Quadrivalent: Fluarix Tetra Alpharix Tetra Influsplit Tetra

Quadrivalent:

Belgium, France, Germany, Italy, Spain, Switzerland, UK

Quadrivalent intramuscular

Seqirus

Trivalent:

Agrippal Fluvirin

Trivalent:

All EU/EEA countries

Inactivated/ subunit

None

intramuscular

Egg

From 6 months

Adjuvanted trivalent: Fluad

Adjuvanted trivalent:

Germany, Italy, Spain, Sweden, UK

Squalene (MF59

From 65 years

Omninvest

Trivalent:

Fluval AB

 

Hungary

Inactivated

Aluminium phosphate gel

intramuscular

Cell

From 6 months

Pfizer/CSL Australia

Trivalent:

Afluria*** Enzira

 

Inactivated  

None  

intramuscular  

Egg  

From 5 years, however increased fever reported in children 6 months to 5 years

Sanofi Pasteur

Trivalent:

Vaxigrip**

 

 

 

Trivalent:

Available in all EU/EEA countries

Inactivated  

None  

Intramuscular/ subcutaneous  

Egg  

From 6 months  

Trivalent:

Istivac

Portugal, Spain

Intramuscular/ subcutaneous  

From 6 months

Trivalent:

Mutagrip

Italy, Spain

Intramuscular/ subcutaneous  

From 6 months

Trivalent:

Intanza

 

Austria, UK

Intradermal

From 18 years

Quadrivalent:

Vaxigrip Tetra

Quadrivalent:

Austria, Belgium, Bulgaria, Croatia, Czech republic, Estonia, Finland, Germany, Greece, Hungary, Italy, Ireland, Latvia, Lithuania, Malta, Poland, Romania, Slovenia, Sweden, UK

Intramuscular/ subcutaneous  

From 3 years

* The same product may be sold under different names ** Split virion by Triton X-100 and formaldehyde inactivated *** Beta-propriolactone-inactivated and taurodeoxycholate- split virion vaccine

As noted above three vaccine manufacturers currently offer tetravalent influenza vaccines on the EU/EEA market: AstraZeneca, GSK and Sanofi Pasteur. These vaccines are as of 2017 only authorised in a limited number of EU/EEA countries. In most countries where quadrivalent vaccines are available there are still also trivalent influenza vaccines being used dependent on procurement agreements with different health care providers.