AstraZeneca’s CEO has suggested that its Covid vaccine, developed with the University of Oxford, may be playing a role in the UK’s relatively low rate of hospital admissions, despite a high rate of infection. Pascal Soriot told BBC Radio 4’s Today program that, unlike much of Europe, the UK had used the AstraZeneca vaccine in many older people. He said his company’s vaccine is known to stimulate the T-cell part of the immune system to a higher degree in this group. Unlike antibodies, which decline over time, T cells have a longer immune response, although they may take time to react to infection. So Mr Soriot suggests that this may explain why the virus can circulate without causing as much hospital admissions as in other European countries.