On Jul. 8, 2020, the European Commission announced regulatory approval for the first adjuvanted quadrivalent influenza vaccine to become available across Europe. The new quadrivalent vaccine is specifically designed to protect adults aged 65 and over against four strains of seasonal influenza: two A strains along with two B strains, as opposed to a two A strains and a single B strain in the current vaccine.

The new adjuvanted quadrivalent vaccine (aQIV) will be manufactured in Liverpool, UK, by Seqirus, one of Europe’s largest influenza vaccine producers and a global leader in influenza prevention.  In the 2018/19 influenza season, when aTIV was the main vaccine recommended in the 65+ age group in the UK, an analysis by Public Health England3 showed that overall adjusted influenza vaccine effectiveness for the aTIV against medically-attended laboratory confirmed influenza was 62% (3.4%, 85.0%). In recent influenza seasons prior to 2018/19 when all age groups 18+ were given non-adjuvanted influenza vaccines in the UK, vaccine effectiveness in the above 65 age group tended to be lower compared to the 18-64 age group.

Adding the additional B strain to the new vaccine can provide additional coverage, particularly in influenza seasons where B strains are more dominant, such as 2017/18. In that season, nearly half of all deaths from influenza in intensive care units reporting data to the European Centre for Disease Prevention and Control were due to B strain viruses.

Older people see a natural decline of their immune system with age, which makes them more vulnerable to becoming seriously ill with influenza. Ageing can also reduce the body’s immune response to influenza vaccination. The adjuvant added to aQIV is designed to boost the immune response in older adults, and to help compensate for this effect.

Seasonal influenza is a common, highly contagious infectious disease that can cause severe illness and life-threatening complications in many people. The European Centre for Disease Prevention and Control estimates that 15,000-70,000 people in Europe die from influenza-related complications each year, and encourages annual vaccination as the most effective way to prevent influenza.