Seasonal influenza is caused by influenza viruses that circulate in all parts of the world. Worldwide, annual epidemics are estimated to result in three to five million cases of severe illness, and 290,000 to 650,000 deaths due to respiratory complications. The most effective way to prevent the disease is vaccination.
In 2004, Derek Smith at the University of Cambridge published a new bioinformatics method, antigenic cartography, which is a simple visualisation of antigenic data in the form of an ‘antigenic map’ that greatly improves our ability to see and understand pathogen evolution.
As a result, the research of Smith’s team on the evolution of the influenza virus has been an integral part of the World Health Organization (WHO) influenza vaccine strain selection process since 2004, with Smith sitting on the committee that chooses the vaccine strains every six months.
Furthermore, Smith and his team recognised that by understanding the mechanism behind the evolution of seasonal influenza viruses it may be possible to predict the evolution of its antigens (the parts of the virus that generate an immune response) with reasonable accuracy, potentially enabling antigenically advanced or ‘evolution proof’ vaccines to be deployed. In such a scenario, populations could be vaccinated against strains yet to occur in nature through a process the Cambridge group refers to as immunity management.
Further research led to the possibility of predicting the evolution of human seasonal influenza viruses, and to improvements in our understanding of the immunity induced by influenza vaccination.
Since 2017, this work has generated a profound change in the vaccine strain selection process by WHO. An estimated 500 million people are now vaccinated annually with strains informed by this work.