Something was tickling Sam's throat. He kept trying to clear it, but it didn't work. Drinking more water helped for a bit though.

After about an hour of research, Dean finally arrived at the motel room.
"Anything?" Sam asked.

Dean shook his head. "Nah, nothing like this has ever been recorded to happen before. It's so huge. I mean over 150 infected in the first day, and there's no cure? The whole town'll be wiped out in a week."

"Yeah, tell me about it", Sam said with a slight shake of his head. "I did find something though. And it's bad news."

Dean groaned. "What is it?"

"I found some lore about something called 'The Dark Death'. Here, listen to this; 'The Dark Death epidemic swept through the planet like an unstoppable tsunami. Once the dark smoke inhabited a mind it could not be stopped. It lit a fire within so fatal that every life around it shriveled and died too. This was the work of a powerful darkness, so fierce that God himself felt threatened, and it had only one goal; the destruction of humanity.'"

"That doesn't sound good", Dean muttered. "Lighting a fire within, that must be the fever."

"I know", Sam said. "Worse yet, I think Amara's behind it."

Dean raised his eyebrows. "The darkness? Why?"

"The disease was caused by 'a powerful darkness'?" Sam said, pausing for a cough. "Powerful enough to allegedly scare God? If that doesn't describe Amara then I don't know what will."

"Yeah, I guess you're right." Dean sighed. "So she's planning to wipe out humanity, huh? Why?"

"Well, she's looking for God, right? I guess she figured, what better way to get his attention than destroying his creations."

"Talk about being a bad sister", Dean snorted. "Does it say anything about how to stop it?"

"Well, it sounds more and more like it's a spell of some kind. A very powerful one. But there's a part here that makes me think it's attached to an object, and that's how it stays anchored on earth. Instead of keeping it going with her own power, she linked it to an object."
"What object?"

"Actually, objects, rather. 'The force of the Dark Death can only be contained by the darkness itself, or by the artifacts of the darkest of deeds. An object drenched in the blood of betrayal. To destroy such a powerful artifact can only the blade of light.'"
"My god, can they be any more subtle", said Dean with a roll of his eyes. "Okay, so if the disease isn't linked to Amara, then it's linked to an object drenched in the blood of someone betrayed, so someone murdered?"

"I think so, yes", Sam said. "And to destroy it we'll need a Holy Knife."
"Holy Knife, that's new. How do we get one of those?"

"I'm not sure, but-" Sam was interrupted by another cough attack. He covered his mouth with his hand, and when he removed it, he could only stare at it for a while. It was spotted with blood.

"Sam?" Dean said, frowning. "What's wrong?"

Sam looked from his brother down to his hand again, before another cough tore through his body, more violent this time.

"You're sick", Dean whispered.

"I'm sick", Sam repeated, stunned.

How?

His brother suddenly reached toward him, but Sam quickly jumped out of the way, covering his mouth with the sleeve of his shirt. He turned and ran into the bathroom, slamming the door shut after him and locking it.

"Sammy?" Dean's voice called from the other side of the door. "Sam, let me help!"

"No, Dean", Sam said. "We're of no use to anyone if we're both dead. You've got to stop this disease."
"Damn it, Sam." Dean banged at the door. "If this is what we think it is, you'll be dead in a day!"

"Then go find something that belonged to someone who was murdered and destroy it. That's the only way you can help me."

Whatever Dean said next, it was drowned by Sam's next cough attack. He spat the blood out into the sink and tried to rinse his mouth with water to get rid of the taste. Then he sank down to the cold, tile floor, leaning against the bathtub.

He heard Dean swear, then shuffle around the room before knocking at the bathroom door again. "Alright, I'm heading out. I'll be back soon. You stay alive, you hear?"

"Of course", Sam said, voice raspy.

oooOOOooo

"Hi", Dean said, standing at the reception in the police station. He held up his FBI badge. "I need to have a look at the most recent, close-by murders in town."

The police officer at the reception frowned. "What for?"

Dean was used to questions by now; not everyone was completely blindsided by the sight of FBI. So he put on his scary-face. "It's classified. And I'm sure that you're not going to stand in the way of a federal case?"

The officer sighed, but left his chair to lead the way to the record room.

Dean shuffled through the files as fast as he could, but trying to find a case where the victim had bled on some kind of object that weren't then donated or thrown away, but kept by the relatives, proved difficult.

After 45 minutes of reading, he finally found it. Heath McNeal was murdered by his girlfriend, stabbed in the chest. Cause of death: left ventricle torn, bled out.

Guess she thought a literal broken heart served him right.

There were pictures of the crime scene, and the blood was everywhere.

Dean shoved the other records back in their shelves and returned to the desk. He dropped the file in front of the officer. "Is it possible for you to track where Heath McNeal's belongings went after his murder?"

"You're here for the McNeal case? It was sold several months ago, the girlfriend's in prison."

"Yeah, yeah, we're not here about her. Now, you didn't answer my question."

The officer frowned, but nodded. "I guess it's possible. But it'll take a while."

"That's fine," Dean said, slumping into one of the chairs. "Just try to hurry."

He read through McNeal's file again while he waited. Heath's house was about two hours away, but it was the closest case he could find that fit the requirements.

After another 30 minutes the desk officer finally turned around. "His belongings were kept by his younger brother, in that same house."

Dean nodded and rose from the chair. "Alright, thanks."

He dropped the file on the desk again before he left.

A/N: It's definitely going somewhere now! Thanks for all the reviews on my first chapter, it means a lot. I hope you liked this one too, please keep commenting your thoughts.