Since the last episode in February, a lot has happened with the vaccination rollout -- so we're back for a few more episodes. But we've changed our name from The CoVax Files to The Vax Files, which was was done mainly to avoid any confusion with GAVI/WHO's COVAX facility and also to maintain our independence from any official organization. As we approach the end of 2021 and almost 7 billion administered vaccine doses, we now have a good chunk of real world effectiveness data available. During this episode, experts walk us through some important datasets that can speak to how the vaccines have been working, with particular nuances around the emergence of the highly transmissible Delta variant. Experts take a deep dive into real world evidence data in different countries to elucidate overall protection, antibody waning, protection against severe disease and death as well as the likelihood of transmission when vaccinated. Finally, experts discuss the dangers of misinterpreting headline or summary data, which has been a regular occurrence in the media and social media during this pandemic. Expert Guests:

-- Dr Jeffrey Morris is Professor of Biostatistics and Director, Biostatistics Division at the University of Pennsylvania, US. His research focuses on developing quantitative methods to extract knowledge from biomedical big data and he set up a blog dedicated to issues concerning the Covid-19 pandemic.

-- Dr Nikolai Petrovsky is Professor of Medicine, Flinders University, Adelaide, Australia and vice-president and secretary-general of the International Immunomics Society. He is the founder of vaccine biotech, Vaxine, which has a protein based vaccine for Covid-19 in its pipeline.

-- Dr Maria Elena Bottazzi is the Associate Dean, National School of Tropical Medicine and Professor of Pediatrics (Tropical Medicine) and Molecular Virology and Microbiology at Baylor College of Medicine, Texas, US. She is a leading expert in the field of vaccine development and tropical diseases.

-- Dr Andrew Read is Professor of Biology and Entomology at PennState University, US. His research specializes in the ecology and evolutionary genetics of infectious disease, which includes the impact of vaccination on virus evolution.