Why we might not get a coronavirus vaccine

Politicians have become more cautious about immunisation prospects. They are right to be

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It would be hard to overstate the importance of developing a vaccine to Sars-CoV-2 - it's seen as the fast track to a return to normal life. That's why the health secretary, Matt Hancock, said the UK was throwing everything at it".

But while trials have been launched and manufacturing deals already signed - Oxford University is now recruiting 10,000 volunteers for the next phase of its research - ministers and their advisers have become noticeably more cautious in recent days.