Influenza vaccine production technologies: past, present and future

Abstract

Influenza is a constantly evolving global health threat that leads to substantial morbidity and mortality particularly in vulnerable populations at either end of the age spectrum. Society has responded by creating a global public-private system that involves constant surveillance, candidate virus generation, and release reagent generation linked to worldwide influenza vaccine manufacturing capabilities. It was initially recognised that influenza circulates as multiple antigenically distinct subtypes, which led to the generation of vaccines containing multiple influenza strains. The first and still current major process used for influenza vaccine production is infection of embryonated hen's eggs with influenza virus. While this approach was a true advancement, some shortcomings such as lack of vaccine match to circulating strains due to egg adaptation and production capacity limitations have led to recent innovations in mammalian cell production and synthetic technologies aimed at further improving global influenza responses.