It started late. When the prime minister took his seat at the head of the table in that windowless, subterranean room, the conversation died. This was the first prime ministerial COBRA since the outbreak in Svalbard at the beginning of the week. Ajay Chakrabarti was not present at the meeting, but before it had begun he had gone downstairs and personally checked that there was a numbered and bound copy of the CRIP printed out and laid neatly on the table for every minister and official attending.

‘This meeting,’ the PM told those present, ‘is to establish what we know about this outbreak, who we think is behind it, and what we need to do to prepare for the worst-case scenario, should that develop.’

Jay Spelling, the health secretary, seated on his right, was nodding vigorously.

‘Dr Gall,’ the PM said, ‘will you give us your findings, please.’

The Porton Down scientist took a deep breath, placed her spectacles on the table in front of her, then shared with them the full horror of what her team in Wiltshire had discovered.

‘Marburg,’ she said, ‘is a filovirus. It’s one of a group of haemorrhagic viruses, like Ebola, that can result in uncontrolled bleeding from every orifice. You may recall the Ebola outbreak in West Africa in 2014?’ Several nods around the table. ‘Well, that killed over eleven thousand people across six countries. The more recent outbreak in the DRC killed at least fifteen hundred people in just the first ten months.’ She stopped as a hand went up. It was the defence secretary, an ex-RAF Typhoon pilot and another recent appointee to his post.

‘I’m sorry,’ he said, ‘but I’m not quite getting this. I’m not playing down those numbers, Clarissa, they’re bad enough. But, come on, they’re dwarfed by the death toll from Covid-19. The world saw, what, nearly two million deaths, I think it was, from Coronavirus in 2020 alone. This Marburg thing doesn’t sound like it’s anywhere near that level. Or am I missing something here?’

The expression on Dr Gall’s face said it all: Yes, you’re completely missing the point and you also cut me off before I’d finished. She smiled at him patiently before continuing in a calm, measured tone: ‘There are two reasons why we need to worry, Secretary of State. One is that, unlike Covid-19, which was naturally occurring in the animal population, this virus has been deliberately genetically engineered. The second is that this isn’t just one pathogen we’re looking at here, it’s two.’

The PM’s head hung low as he listened, passing a hand across his face, as if trying to wipe away what he was hearing. When he said nothing Dr Gall continued, ‘Some of you may be familiar with monkey pox. It’s related to smallpox, but it hasn’t been eradicated. It’s been cropping up in Nigeria and—’