Influenza Vaccine

George Kassianos, MD, on Influenza Vaccination Efforts in the UK and Lessons Learned

Worldwide, influenza virus is responsible for an estimated 3 to 5 million cases and 290,000 to 650,000 respiratory deaths each year.1 Influenza vaccination is an important component of not only prevention of influenza virus, but also management, as the vaccine can help reduce the severity of illness, hospitalizations, complications, and mortality among those who acquire influenza.2

In the United Kingdom, recommendations for influenza vaccination previously focused on elderly and at-risk groups, such as individuals with underlying health conditions (including children aged 6 months or older with chronic disease).3 Following a 2012 recommendation from the Joint Committee on Vaccination and Immunisation (JCVI), the UK’s National Vaccination Programme was extended to include healthy children and adolescents aged 2 to less than 17 years, and has been phased in over the course of several influenza seasons to include broader childhood age groups.3 Children included in the program received the intranasally administered live attenuated influenza vaccine (LAIV).3

According to the authors of a recent review of the program and its effectiveness, its impact has been “good to excellent,” and it has been associated with positive influenza-related outcomes.3 Infectious Diseases Consultant discussed these findings further with lead author George Kassianos, MD, National Immunisation Lead for the Royal College of General Practitioners in the United Kingdom.

ID CON: Why was intranasally administered LAIV the vaccine of choice for children in the UK’s National Vaccination Programme for influenza?

Dr Kassianos: In 2012, the JCVI was looking for a vaccine for children that had long-established use, had a good safety record, had a potential to protect to a degree against drifted strains, had the potential to induce better immune memory by replicating natural infection, that was superior to the inactivated non-adjuvanted influenza vaccines we had at the time and, of course, was licensed for children. The vaccine that was chosen was the intranasal LAIV with the trade name Fluenz.

ID CON: Could you elaborate on the positive effects of the UK’s National Vaccination Programme on influenza-related outcomes?

Dr Kassianos: The UK’s National Influenza Vaccination Programme for children has proven to be a great success. From the start of the vaccination program, we organized pilot areas (distinct geographical areas where we offered the vaccine to primary school children aged 5 to 10 years and 2 cohorts from the secondary school age 11 to 13 years). We were able to compare these pilot areas to non-pilot areas where children were not offered the intranasal vaccine.

No matter which parameter we examined, there was a difference between the pilot and the non-pilot areas, favoring the pilot areas. In some areas, the difference was statistically significant. There was a relative risk reduction of 94% among primary school children in the pilot areas. Among primary school children visiting their general practitioners (GPs) with influenza-like illness, there was a 74% reduction in visits to accident and emergency (A&E) departments with respiratory symptoms, and there was a 93% reduction in influenza-related hospital admissions. As it is widely known, children are the best and most effective spreaders of influenza viruses. In the pilot areas, there was a relative risk reduction of 59% among all individuals aged 18 years or older for visiting their GPs with influenza-like illness.

ID CON: What are some lessons that can be learned from the UK’s National Vaccination Programme for influenza in other countries, especially in countries where vaccine hesitancy and anti-vaccine sentiments are not uncommon among parents of young children?

Dr Kassianos: Vaccination of healthy children protects them from contracting influenza and going to hospital A&E departments with respiratory symptoms or being admitted to the hospital with influenza. To make sure our children remain healthy, it is of paramount importance that we ensure they get vaccinated against influenza. Another benefit that results from extending influenza vaccination to healthy children is that they spread much less influenza viruses to their parents, teachers, grandparents, friends, and others.

ID CON: What areas of future research are needed going forward when it comes to influenza vaccination strategies for children?

Dr Kassianos: We have done the research we need. We now need to extend influenza vaccination of healthy children to all ages. In the influenza season to come (2020-2021), children aged 6 months to less than 2 years and 13 to 17 years in the United Kingdom will only receive the influenza vaccine if they have a chronic disease–that is, if they are in one of the clinical groups defined as “at risk.” We need to extend vaccination to healthy children as well in these cohorts, and children aged 2 to 12 years will be offered the intranasal influenza vaccine.

ID CON: What key takeaways do you hope to leave with infectious disease specialists and related health care providers on this topic?

Dr Kassianos: Vaccination of healthy children is clinically very important, as it considerably protects the health of our children. From the financial point of view, it is very cost-effective. From a societal point of view, vaccination of healthy children statistically significantly reduces circulation of influenza viruses in communities where healthy children are also offered the influenza vaccine. From a medical point of view, vaccination of healthy children, as well as all other age groups, against influenza protects them against influenza and its complications. Such is the power of vaccination!

—Christina Vogt

References:

  1. Influenza (seasonal). World Health Organization. November 6, 2018. Accessed July 27, 2020. https://www.who.int/en/news-room/fact-sheets/detail/influenza-(seasonal)
  2. What are the benefits of flu vaccination? Prevent flu. Seasonal influenza (flu). Centers for Disease Control and Prevention. Page last reviewed December 3, 2019. Accessed July 27, 2020. https://www.cdc.gov/flu/prevent/vaccine-benefits.htm
  3. Kassianos G, MacDonald P, Aloysius I, Reynolds A. Implementation of the United Kingdom’s childhood influenza national vaccination programme: A review of clinical impact and lessons learned over six influenza seasons. Vaccine. Published online July 21, 2020. doi:10.1016/j.vaccine.2020.06.065