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As the Delta variant becomes dominant around the world, fully vaccinated people are becoming infected with COVID-19. These so-called 'breakthrough infections" have raised questions about the effectiveness of the vaccines. Data from some countries with high vaccination rates are also now showing more weekly cases of COVID-19 in vaccinated people than in the unvaccinated - does this mean the vaccines aren't working? Join some of the world's leading vaccine experts at this briefing from the global Science Media Centres and our partners in the COVID-19 Vaccine Media Hub. The briefing will discuss the following issues: How can we make sense of the vaccine efficacy data? Just how effective are the vaccines against the Delta variant? Do the vaccines prevent transmission? Can any countries actually reach herd immunity? Will we need booster shots in the coming months?
As the Delta variant becomes dominant around the world, fully vaccinated people are becoming infected with COVID-19. These so-called 'breakthrough infections" have raised questions about the effectiveness of the vaccines. Data from some countries with high vaccination rates are also now showing more weekly cases of COVID-19 in vaccinated people than in the unvaccinated - does this mean the vaccines aren't working? Join some of the world's leading vaccine experts at this briefing from the global Science Media Centres and our partners in the COVID-19 Vaccine Media Hub. The briefing will discuss the following issues: How can we make sense of the vaccine efficacy data? Just how effective are the vaccines against the Delta variant? Do the vaccines prevent transmission? Can any countries actually reach herd immunity? Will we need booster shots in the coming months?
• Professor Kim Mulholland is a Professorial Fellow at the University of Melbourne Department of Paediatrics, and Group Leader, Murdoch Children’s Research Institute, Melbourne. He is also Professor of Child Health and Vaccinology at London School of Hygiene and Tropical Medicine, Honorary Professor, University of Nagasaki, Japan and Honorary Professor, National Center for Communicable Diseases, Mongolia. He is a member of the WHO's Strategic Advisory Group of Experts on Immunization (SAGE). This group advises the WHO on overall vaccine policies and strategies.
• Prof Neil Ferguson is an epidemiologist and Director of the MRC Centre for Global Infectious Disease Analysis, Imperial College London. He leads the Imperial College COVID-19 Response Team.
• Associate Professor Helen Petousis-Harris is a vaccinologist, and the Director of the Vaccine Datalink and Research Group at the University of Auckland. She is co-leading the Global Vaccine Data Network, a multinational consortium dedicated to collaboration in vaccine safety studies and was previously the chair of the World Health Organization Global Advisory Committee on Vaccine Safety (GACVS)