When you talk to intensive care doctors across the UK, exhausted after weeks of dealing with the ravages of Covid-19, the phrase that emerges time after time is, "We've never seen anything like this before."
They knew a new disease was coming, and they were expecting resources to be stretched by an unknown respiratory infection which had first appeared in China at the end of last year.
And as the number of cases increased, doctors up and down the UK were reading first-hand accounts from colleagues in China, and then in Italy - in scientific journals and on social media - about the intensity of infection.