In other circumstances, Rose would have been quite impressed by the palace and its lavish grounds. However, her thoughts centered on the ill children, and she barely noticed her surroundings.
They were ushered to a wing on the far side of the palace. Inside they found a facility resembling a small hospital. They were greeted summarily by a middle-aged man who Marden introduced as Dr. Wembur, the Royal Physician. Upon his introduction to the Doctor, his natural questions about the Time Lord's qualifications were silenced with a flash of the psychic paper and a jumble of jargon that Rose scarcely understood. Dr. Wembur, however, did, at least for the most part, and she could tell that the Doctor's presence was very welcome.
The children were settled into beds, and Rose was escorted to a well-appointed room and left to sit idly upon the sofa. When she stood and tried the door, she was not terribly surprised to find it locked. She sighed and sat down again.
After some time, the lock clicked and the Doctor stepped through the door. His expression remained somber, but he managed a tight smile when she greeted him.
"You headin' back to the TARDIS now?" she asked.
He shook his head. "Wish I could. My lab makes the one here look like a child's basic chemistry set. But I'm having trouble convincing them of that."
"You? You're the most convincin' person I know!" Rose protested.
"Not this time. Problem is that I've already told them we're visitors, and the psychic paper showed them that I'm from a principality about 800 miles away."
"Why'd it do that?"
"It shows people what they expect to see. Marden told them that we're visiting, and I suppose they assumed we were from far away. Anyway, I can't get them to believe that I can reach my lab in a matter of hours—transportation here isn't that advanced yet—and I didn't want to force the issue. I can still help them here, but not if they decide I'm some sort of crank."
"Can you make an antibiotic, or whatever it is they need, here?"
"I should be able to. Their labs aren't terribly sophisticated, but all I really need are some decent microscopes, a centrifuge, and some other basic equipment. They've got all that."
"So what're you gonna do?"
"Have you ever heard of the side-chain theory of immunity? At least I think that's what you lot call it."
Rose shook her head.
"No? Suppose they aren't teaching that in biology classes, but they should. Anyway, the side-chain theory of immunity became the theoretical basis for the creation of laboratory-based antitoxins. It was used on Earth in the early part of the twentieth century to develop an antitoxin serum for diphtheria."
Rose had never found science particularly interesting until she met the Doctor. Now she was fascinated. "Yeah? How's it work?"
"In the original studies, a sublethal dose of diphtheria was injected into animals, which caused the animals to produce disease-fighting antibodies in their own blood. Blood was taken from these animals, and the serum was found capable of neutralizing the diphtheria toxin in humans. This basic idea's led to the creation of all sorts of wonderful disease-fighting drugs."
"So you think you can produce an antitoxin from animals' blood?" Rose clarified.
"Not exactly. That's the basic theory, but in this case we'd need to use human blood serum. If we can find someone with immunity to the disease—someone who survived the last outbreak—we may be able to create a simple but effective antitoxin."
Rose knew the Doctor well enough to distinguish the slight hesitation in his tone. There was some sort of hitch in the plan; she was rather familiar with that. "But there's a problem, isn't there? You said 'may be able'."
He nodded. "Yes. Two problems, really, but one is relatively easy to deal with. The first has to do with creating the antitoxin. Science here, bacteriology in particular, isn't quite ready for the side-chain theory of immunity. They'll discover it on their own within a few years, of course, but not today or tomorrow. So if I tell them about it, I'd be altering their timeline, and we both know the potential consequences of that."
Rose grimaced involuntarily at the memory of the Reapers. "Can you do the work without explaining it to them?"
"I think so. I've been given full access to the labs, and I can probably be vague enough in my explanations that I won't reveal the full theory."
"So that problem's fixable. What's the other one?"
The Doctor sighed and rubbed at his eye. "In order to produce the antitoxin, I'd need blood containing antibodies, and there aren't a lot of people around who survived the outbreak sixty years ago."
"Ilaine's mother did," Rose reminded him.
"She died two years ago."
"But there must be others."
"Of course. Problem is that there aren't many. This disease has a seventy to eighty percent mortality rate in children, and those who do survive often end up with permanent coronary or liver damage, which shortens their life spans."
"Oh God, seventy to eighty percent?" she repeated. "That's terrible. Doctor, you have to find someone. You have to make the antitoxin to save those children."
"Marden's organized a search, but it may take some time to find a survivor. And even if we do, the antibodies may be too weak to produce the antitoxin. Anyone we find would have recovered sixty years ago. Antibodies are strongest in those who've recently fought off the disease."
"An' what about in all the adults with inherited immunity?" Rose asked.
"That was my first thought, actually. I'm testing Ilaine's and Marden's blood now; I introduced infected blood to the slides to see if their blood would actively produce antibodies to fight the virus. There wasn't any significant reaction last I checked, but Dr. Wembur's keeping an eye on the samples."
As if on cue, the physician appeared at the door. His face was bleak. "It's not working," he reported succinctly.
"No reduction in viral cells at all?" asked the Doctor.
"None."
"Then we'll just have to hope that we can find a survivor," the Doctor replied.
With a bleak nod, Wembur said, "Excuse me. I need to check on the Prince."
"How are the other children doin'?" Rose asked before he stepped away.
"Their conditions are stable at the moment, but they'll grow worse over the next twenty-four hours." Wembur turned and walked away.
"Damn it," the Doctor said. "It was a long shot, but I was really hoping that would work."
"Maybe one of the survivor'll turn up and still have enough antibodies—" Rose began.
"Maybe," he interjected. "But that's going to take time—time to find them, time to bring them here. And time's something we don't have a lot of."
"Time," Rose murmured. "How long will the children be sick?" she asked rather abruptly.
"The disease usually lasts from forty-eight to seventy-two hours; it's got a fairly rapid onset and course."
"Is it the same for adults?"
"It's a bit faster—comes on more quickly and runs its course within about thirty-six hours."
"You said mortality's high for children. What about for adults?"
"Shouldn't be as bad…" He considered the question for several seconds. "I think that something like 90 percent survived during the very first outbreak, but records dating all the way back then are a bit sketchy."
Rose's eyes moved to the door. "If I went out there, sat with the children, helped take care of them—how likely is it that I'd get sick?"
"Very likely, Rose. Without immunity, you'd almost certainly contract it."
"Oh." She thought for a moment. "I might've been exposed before," she began.
"I doubt it."
"But if I was?" she persisted.
His eyes met hers for a brief but intense look. "You're young and healthy. You'd almost certainly survive even without any medication. But if you did get sick, I'd take you back to the TARDIS and treat you immediately, and we'd nip it in the bud. So you don't need to worry. And as I said, it's extremely unlikely that you were exposed. The virus passes through direct contact, and you never touched the boy."
She nodded. "No, I didn't."
He clasped her hand reassuringly and offered her a wan smile. "I should double-check the blood cultures and see if there's anything I can do to make the children more comfortable."
"What can I do? I really want to help."
"Just stay here where you're safe."
He closed the door behind himself but did not lock it. Rose sat for some time deep in thought. Eventually she realized that she needed a bathroom, so she left the room in search of the appropriate facilities. As she wandered down the hallway, she passed the children's sickroom again. The door was closed, but a small glass panel permitted her to see inside.
Ilaine sat beside Raben's bed, her hand resting over his cheek. The boy remained very pale, and she thought his face reflected pain. Ilaine held the baby in her lap; he was fussing softly, and Rose could see that his cheeks were damp with tears. He moved his leg, revealing a bit of skin above his bootie. She suppressed a small gasp when she saw the beginning of a dark weal on the pale flesh of his ankle.
How many more children would be affected? How many would die? Her thoughts spun and whirled, but in the end they coalesced into one inexorable conclusion. She walked calmly to the bathroom and emerged a few minutes later with a placid expression on her face.
Rose pushed open the sickroom door and gently took the baby from Ilaine. The anxious mother did not resist or even question the young woman's actions. She clearly did not realize yet that her younger child was ill. She returned her attention to Raben, who was whimpering softly.
Rose held the baby against her hip with one arm and ran her other hand softly over the ill boy's hair. "'S gonna be all right," she said.
She moved to an empty bed and sat down, cradling the baby in her arms. She bent to kiss his warm forehead then rested her cheek against his. "Hang on, sweetheart," she whispered. "Help's comin' soon."