A/N: Yup, the next chapter is up. (Explanation for 2-year hiatus at end of chapter.) Enjoy!

NIGHTMARES

"John eyed Carson warily. "Temporary residue? Of what? What the hell makes my blood look BLUE?"

Carson's voice was quiet. "The retrovirus."

John Sheppard felt his face drain of blood. The retrovirus? That should have passed through his system a few weeks after he had received the dosage. Although, now that he thought about it, Carson had not said that it would. He felt light-headed and promptly sat down in a vacant chair.

"Colonel Sheppard, I know this is a shock for you—it certainly is for me—but I need to take another sample of your blood." Carson hesitated as John's face went whiter. "Colonel Sheppard?"

He reached his hand out to get a pulse and ended up instead catching the unconscious man. "Bloody hell," he muttered, "why'd I even have him look?" He quickly called a nurse over and together they managed to get him onto one of the gurneys.

Carson quickly took a blood sample and then left John under the watchful eye of a nurse. He gave her orders to get him immediately when John awoke, before heading off in the direction of the lab to check the sample.

It was not as blue as it had been, and the blue was not very strong. It made the blood look slightly purple, instead of the oxygen-rich red color. Regardless, it still was unnatural to look at for long. Carson sighed, the retrovirus had to make a comeback at some point, but why did it choose now of all times?

John Sheppard opened his eyes to the all-too-familiar infirmary ceiling tiles. He rolled over onto his side, discovering that he could and that he was not hooked up to an IV or any other pestering equipment. He sighed as he realized what it meant: he was not staying for the night.

Suddenly he spotted Carson heading his way and John started to sit up.

"Not yet, colonel," Carson advised, "ye're still a wee bit weak from the shock. I took another blood sample from you while you were out, and it's looking more normal, but…"

"But you need me to stay here until it is," John finished for him. He felt the shudder run through him. "Why is the retrovirus picking now, of all times, to flare up?"

Carson could only shrug. "You haven't been getting much sleep in the past week so maybe that could account for it."

John started to shake his head, but stopped before the dizziness could set in. "I've been low on sleep before and it's never affected me like this. So why now?"

Carson sighed. "I'm sorry lad; I don't have anything more to tell you. I need to run some more tests."

John muttered something under his breath that Carson could not hear.

"What was that, lad?"

"I said I hope I'm not turning into another iratus bug."

When Rodney discovered that John was in the infirmary, and being kept there for observational reasons, he went ballistic.

"Why didn't anyone tell me?" he ranted to a stoic Ronon.

Ronon merely regarded him quietly. "You were too busy playing with your toy."

Rodney threw up his hands in despair. "So you decided not to bother me because I have an object that's not going anywhere in the next 48 hours and clearly that's more important than my friend going into the infirmary?"

Rodney began to crutch down the hallway, heading for the infirmary, muttering under his breath about cavemen and science and no-good-friends who didn't tell you they were going to the infirmary and possibly not coming back.

"What is Carson thinking?" Rodney growled as he finally came to the infirmary doors. He entered the room just in time to find John being hooked up to a dozen different machines. John looked up and over with a grim look.

"Hey, Rodney, you're looking good."

"Like you're not," Rodney snapped back. "Why are you back here?"

John shrugged, earning a quiet remark from one of the nurses who was inserting an IV. He flinched as she did so. "Carson decided that he'd better observe me for the night."

"Why?" Rodney started to cross his arms across his chest, but discovered that he would lose both crutches if he did so. Instead he merely got a better grip on his crutches.

John hesitated. "My, uh, blood is blue."

Rodney stared for a moment. "I'm sorry, your what is blue?"

"It's true Rodney," Carson said, returning from the lab where he had been testing the sample. Rodney spun, wincing as his thigh took on more weight than he had meant. Carson gave him a severe look. "And you shouldn't be walking around so much."

Rodney waved his hand. "What's he mean by the fact that his blood is blue?"

Carson sighed and ran a hand through his hair. "If you wait a few minutes, the rest of the group will be here and then I can explain it once, instead of eight separate times."

Rodney fell silent, although he was clearly anxious and only took a seat when Carson threatened to book him into the infirmary if he did not. By the time John was completely hooked up on fluids and machines that would monitor everything from his heart rate to his mental activity, everyone had arrived.

Dr Weir kept glancing between John and Carson, unsure of why she had been called or why John was needed to be kept under observation. Judging by the looks on Teyla's and Rodney's faces, they weren't too thrilled about it either. John looked pained by the whole thing, and Ronon… Well, who could tell what he thought beyond the displeased expression that seemed vaguely murderous?

"Carson, did you call us in to just gawk at Colonel Sheppard, or did you have a purpose for us to come here?" Elizabeth Weir finally asked when it appeared nothing was going to happen anytime soon.

Carson briefly re-checked everything on John for the third time—despite knowing that his nurses were the best in their fields—before turning back to face the motley crew. He took a deep breath to steady his nerves; yes, even he was worried about their reactions from what he was about to tell them.

He flipped open John Sheppard's medical chart, scanned it for a moment, and then began to speak. "A couple months ago, Colonel Sheppard was injected with the retrovirus. It nearly turned him into an iratus bug,"—John shuddered at the memory—"which we were able to reverse after some time. Then, a week or so ago, he had been having trouble sleeping, which led to severe insomnia and hallucinations." Carson paused. "Since we're out here in the Pegasus Galaxy, it's no secret that the wraith are very real or very present in everyone's minds, but to hallucinate about seeing them, and going so far as to shoot in his sleep"—John flinched—"is more than just a problem."

Carson hesitated with the next thing he had to say. "I took a sample of his blood when he came in from the mission." He paused again.

John Sheppard decided to take matters into his own hands. Judging by the expressions on his friend's faces, Carson might not live long enough to explain whether or not the thing could be reversed.

"My blood was blue…with the retrovirus," John said, perhaps a little too quickly.

Everyone turned to stare at him, before turning back to Carson. "Aye, it was more purple-ish than blue, but it was clearly tainted with the retrovirus."

"Is it reversible?" Dr Weir cut in. Her voice was a bit sharp, but that could have been from worry as much as from irritability.

"Honestly? I don't know." He admitted. "The retrovirus was meant to turn wraiths human, but for the opposite to happen…. It should reverse itself temporarily in the next day or two, judging by the blood sample I took a few minutes ago."

"Why would his blood contain remnants of the retrovirus?" Teyla asked, for her benefit as well as everyone else's.

Carson sighed; what was it with the tough questions? "The only thing I could possibly relate it to is the severe lack of sleep from a week ago. The human body has a chemical balance, that once it goes haywire, it tries to recover by surging other chemicals. Generally, the body attempts this for a day or two, but for extended periods, especially when there has been little to no sleep, the chemicals get out of whack." Carson indicated John. "From what I can tell, the body tried to counter the lack of sleep with adrenalin and food. When that failed, it resorted to using whatever was left in the system: in this case, the retrovirus."

"But you said that it should have been gone from my body," John interrupted, fidgeting slightly. He hated being the center of attention, and hated it even more for making everyone concerned about him.

"Colonel, we have very little idea what we're dealing with. As far as I know, the retrovirus should be gone from your system." Carson quickly pressed on. "Also, because it is part of a virus, the body is known to produce antibodies to try and combat it and that your body ended up storing the retrovirus for future detection. When your body ran out of adrenalin and endorphins, it switched to the only other chemical left over."

"The retrovirus," John reiterated. Carson nodded.

"Aye. However, your system is returning to normal, so I think if we watch you just for tonight, you should be good to go tomorrow."

"Will this be a problem in the future?" Elizabeth inquired. "If he doesn't get enough sleep and the retrovirus keeps kicking up, then won't it only be staving off the inevitable?"

Carson shook his head. "As long as he doesn't push himself too hard, he shouldn't be invoking the retrovirus. As it is, the hallucinations were more likely caused by the lack of sleep, than the retrovirus."

"But he still shot me," came Rodney's accusing voice.

"I'm sorry, Rodney," John said, flinching at the hazy memory.

Elizabeth looked around. "So you're just going to monitor him for tonight, and then send him on his way tomorrow?"

Carson nodded. "Aye, that's the plan. Any more questions?"

Rodney raised his hand. "Yeah, hey Sheppard? Can I have your poster for compensation?"

John glared at Rodney. "I thought you had better things to do with your time."

"Oh right…my new toy." Rodney glanced at Ronon, who was ignoring him. Instead, Ronon's eyes were fixed on the equipment beeping quietly.

"What new toy?" John asked, momentarily distracted.

Rodney grinned. "I managed to bring back that device thingy we found on the planet."

"Do you know what it does?"

The grin vanished. "No. Radek and I are working on it."

"Oh." John lay back against the pillows and sighed. "I guess I'll see you more tomorrow then. Holler if you need me."

Rodney nodded. "Get some rest."

"You too," John called after Rodney's retreating crutching form. John sighed, Rodney could be just as bad as he could about not getting enough sleep—but somehow the physicist never ended up awakening dormant abilities or retroviruses.

A/N: So how about that medical terminology? facepalm I blame my zoology lab for making me think of such things…and the fact I'm writing this straight after lab isn't helping matters. I did, however, get another brilliant idea for a story—set further in Season 3 or 4, but I should finish this before starting that one.

Oh, and for those of you curious why it has been so long since I've updated: I tried to put fanfiction behind me. I've fallen in love with creating my own characters, since attempting NaNoWriMo—and being successful twice—and fanfiction just doesn't feel the same. Anyway, it looks like I've been dragged back to finish the story. (Check out the website www (dot) nanowrimo (dot) org, although it's down for the time being .)