Influenza virus remains a public health burden for which recommendations encourage annual vaccination. However, some studies have suggested repeat annual vaccination may have negative effects on influenza virus immunity. This review analyzes immunological mechanisms that may result in reduced effectiveness of annual influenza virus vaccines.

We highlight how the gut microbiome modulates immune checkpoint blockade efficacy in cancer. We outline diagnostic tools for dysbiosis, examine microbiota-centred interventions (e.g., faecal microbiota transplantation, probiotics, dietary changes), and propose clinical strategies. This review underscores their potential to improve ICB outcomes and reduce toxicity.

Ofer Levy, Director, Precision Vaccines Program at Boston Children’s Hospital, reflects on implications of the new FDA Modernization Act 2.0 on accelerating drug and vaccine discovery and development.