On the second day – when Ben was just thinking to himself that he never wanted to see another bowl of the mashed cassava root that was given to them from a huge cauldron three times a day – the guards were approached by two more masked UN men. They spoke briefly and Ben watched as one of the guards pointed in his direction. The masked men started walking towards him and he stood up to receive them.

'Hi, Ben,' one of them said. Clearly they had spoken before, but the fact that these people were all wearing masks meant that one American accent merged into another for him. He nodded. 'Ben,' the man continued. 'I'm afraid I have bad news for you.'

Ben closed his eyes as a sudden hotness ran through his veins.

'The man called Abele. He was a friend of yours, I understand.'

Ben nodded again. 'Kind of,' he said, his voice clipped so that it didn't reveal the emotion he was feeling.

'I'm sorry, Ben. He died about an hour ago. He was too far gone – there was nothing anyone could do.'

Ben took a deep breath. 'Thank you for telling me,' he whispered, doing his best to keep his wavering voice steady. 'Do you have any information about my father?'

There was an ominous pause. 'I'm sorry, Ben. No. It's too early to tell.'

Ben nodded, then turned and walked to the edge of the tent. He desperately wanted to be alone but, since that was not possible, he wanted to get away from anybody who could speak to him in his own language. From the corner of his eye he watched the UN men leave.

He could not get the image of poor Abele that first time they had met at Kinshasa Airport out of his head. Ben had been suspicious of him then – how wrong could he have been? And if Abele had been beaten by this terrible disease – strong, unbeatable Abele – what chance did anyone have? What chance did his dad have? What chance did Ben himself have? His emotions a cocktail of mourning and fear, he collapsed to the ground with his head in his hands. It was down to fate now. All he could do was wait. Now that he knew Abele was dead, the smell of the incinerators seemed ten times worse.

The results arrived the following day.

A masked man carrying a large clipboard entered the tent. He had an air of authority and everyone fell silent as he started reading names out, his American accent struggling with the unfamiliar African sounds. One by one, the villagers stood up and walked to him, terrified apprehension in their eyes. He said something to them that Ben couldn't hear and they were sent outside.

He found himself holding his breath as he waited for his name.

Finally it came. 'Ben Tracey,' the announcer called. Ben stood up and slowly walked towards him.

'Leave the tent and bear to the left.'

'What's my test result?' Ben asked directly.

'Leave the tent and bear to the left.' The faceless man simply repeated his instruction.

Ben nodded curtly, gritted his teeth and stepped outside, accompanied by another UN guard. 'This way,' his companion told him.

He walked over to where a small group of Africans were standing with worried, uncomprehending looks on their faces. Every now and then, someone else would join them; but they were few and far between – most of the villagers were sent elsewhere. Where it was, Ben couldn't see.

Finally the man holding the clipboard approached. He walked straight up to Ben.

'Ben Tracey?'

Ben nodded. He didn't trust himself to speak.

'I'm giving you the news first,' he said flatly. 'The others will have to wait for an interpreter.'

'OK.'

'Samples have been taken from those infected with the virus so that we can isolate the specific antibody that fights it. You have been tested for that antibody.'

Ben wished the man wasn't wearing a mask – that way he might have been able to read something into his expression. But he couldn't.

'Only about one third of the population carry this antibody,' he continued. 'I'm happy to inform you that you are one of those.'

Ben felt his knees buckle beneath him with relief; it was all he could do to stand up straight. 'Thank you,' he whispered. It seemed inadequate somehow.

But then the man spoke again, and his robotic voice sounded softer this time, more sympathetic. 'Ben, I need to talk to you about your father.'

He felt a chill cover his body.

'He's very ill, son. You know that, don't you?'

Ben nodded silently. He wasn't sure if he could bear to have this conversation.

'We don't know what this virus is yet. But we do know that it attacks the vital organs, starting with the lungs, then the blood, then the brain. Even the strongest people have difficulty withstanding such an attack. It's random, who survives and who doesn't.'

Ben lowered his eyes. It was clear what the man was trying to say. Half of him wished he would just spit it out; the other half didn't want to hear it.

And then the man was talking again. 'You need to prepare yourself, Ben…'

Ben closed his eyes.

'… prepare yourself for the fact that he might not be the same again.'

Ben blinked. Had he heard him right? 'You mean…?' he faltered.

'It looks like your dad is going to pull through.'

Ben's breath left him like an explosion. 'But there's a possibility that he will be left severely disabled by his illness, Ben. The British Embassy in Kinshasa has been informed of his position, and they're sending transport back for you as soon as we've confirmed that neither of you are contagious any more. They've also contacted your mother, who is flying over to meet you both.'

'Can I see him?'

'Not yet. You both need to be isolated for a couple more days. But we're going to get you out of here as soon as we possibly can.'

Ben looked around him. 'What about everyone else?'

'They won't be so lucky, I'm afraid. The people who are immune to the virus will be kept isolated from the others. Those who succumb will be taken to the medical tent, where they'll receive our best attentions.

Most of them won't make it.'

Ben's face became severe. 'There's a girl called Halima. I need to know how she is.'

'I'm sorry, Ben. I just don't have that information and we're going to keep you away from everyone else – so you can forget about seeing anyone apart from your dad. But you need to prepare for the worst – it's going to be pretty rough here, for a few months at least. A lot of people are going to die. But if we hadn't closed down this village and blocked up the mine in time, it could have been a million times worse. Word is, we've got you to thank for that.'

Ben averted his eyes. It seemed a hollow victory. 'I had a lot of help,' was all he could think of saying.

'Whatever,' the man from the UN replied. 'If anyone deserves to get out of here, it's you.'

He put a gloved hand on Ben's shoulder.

'We're going to get you home, son. We're going to get you home real soon.'