2. Diagnosis

AN - This was originally going to be a story about Mumps, but then I realised that that particular diseases' impact on male fertility is neither common nor long term – and besides which Sherlock really wouldn't care! So, I had to find an illness he would worry about!

The house was a relatively modest Victorian terrace on a nice tree lined street within walking distance of the tube station and local amenities as Estate Agents liked to say. The only thing that distinguished it from its neighbours was the layers of scaffolding across its half painted exterior, the yellow crime scene tape presently cordoning it off and the muted sounds of a child crying inside.

"There's no body?" Sherlock scowled as he followed Lestrade under the yellow tape, taking a moment to glare at the DI as he waited for John to pay off the taxi, so the three of them could proceed through the door into the tiled hallway together, where various crime scene officers milled around them. The sounds of the child's crying got louder. "Then what exactly am I doing here?"

"You like the strange ones," Lestrade shrugged. "This is about as strange as it gets. Elizabeth Harrison, aged 34, kissed her husband goodbye when he left for work at 7.45am. At the same time Malcolm Simpson Ltd arrived to finish off painting the front and back of the house. At 7.30am she brought them all a cup of tea and went back into the house. At 7.45 the child started to cry. At first the guys thought nothing of it, but the kiddie kept on crying. Finally, when they couldn't raise anyone inside the house, they called the police. When the uniforms arrived and broke down the door Mrs Harrison had simply vanished."

"So there were painters at the front and back of the terraced house. Yet somehow Mrs Harrison disappeared into thin air," Sherlock began to speak his thoughts aloud, only to physically flinch as the child's cries reached a crescendo, his own voice rose to a similar level of pique. "I can't think with these distractions? Can't someone make that noise stop!"

"PC Atkins has been trying for the last thirty minutes," Lestrade pointed out. "Her father is on his way. In the meantime, nothing we have tried has made any difference. She just keeps asking for Bugs."

"Insects?" Sherlock frowned. "Why would a child that age be remotely interested in entomology?"

"I think he meant Bugs as in Bunny, probably a stuffed rabbit," John supplied. At Sherlock's blank look he clarified. "Bugs Bunny, the cartoon rabbit, didn't you watch any television as a child?"

The way that Sherlock held his gaze for a fraction longer than necessary, coupled with the slightest twitch of a muscle in his cheek, made John regret raising the apparent deficiencies of his flatmate's childhood in such a public forum. He cast his flatmate a genuinely apologetic look. Sherlock eyes softened very slightly.

"Can't you just give her the rabbit?" His solution was pure logic.

"We've searched the house from top to bottom and we can't find the blessed thing," Lestrade supplied tiredly. "Atkins tried her with a different toy but it just made her cry harder. I suppose we could go and buy her another rabbit."

"Waste of time," Sherlock dismissed that. "Even if you could find the exact same rabbit, to her it will be nothing like the one she has lost. It's colour would have faded from frequent washing. Even so, there would residual stains of the fabric, transferring a familiar smell and the blanket itself would be well worn, resulting in a particular texture that even a child of that age could easily .."

Sherlock stopped, mid flow, his face taking on that look on concentration that said he had pieced together a particularly tricky piece of evidence.

"Sherlock?" John prompted.

"Washing machine," Sherlock declared. "Where is it?"

"In the kitchen."

John tried to make up for his earlier lapse by keeping any trace of censure out of his voice. He had already discovered that Sherlock had no idea how the washing machine worked and no wish to fin d out. He used a laundry service that collected and delivered all his laundry needs. It went without saying that the proprietor owed Sherlock a favour so provided the service for free. He had generously offered to extend this facility to John, but the doctor had felt awkward about living off Sherlock's reputation and had insisted on using the dilapidated machine in the small room off the basement.

Sure enough when John located and opened the family's washing machine, there nestled among a tangle of sheets and pillowcases was a slightly damp, purple floppy eared rabbit. John grinned in genuine appreciation at this unequivocal evidence that Sherlock's deductive abilities knew no limits. Lestrade just breathed an immense sigh of relief that the girl might finally settle down and Sherlock looked insufferably smug as he reached in and plucked the stuffed rabbit to safety, carrying it to where Atkins was holding the crying child like a King about to bestow a knighthood.

"It doesn't seem to have made her any happier," Sherlock observed after a moment. "Not to mention, any quieter."

"She's not crying because of the rabbit." John spoke up.

"Well, obviously not only because of the rabbit," Lestrade agreed. "She did just wake up all alone in an empty house and nobody seems to know where her mother might have gone."

"I don't think that's why she's crying either, or at least not entirely," John knelt down on the floor in front of Atkins so he could get a closer look at the child. "What's her name?"

"Jezelbel," Sherlock supplied. "Unfortunate, but true."

"How could you possibly know that?" Lestrade wanted to know.

"Her coat was hanging in the hallway," Sherlock supplied. "It had a name tag inside. Unless, you are hiding any more 4-5 year old girls around here whose favourite colour is clearly purple, judging by her dress, shoes and tights, not to mention the predominant colour of "Bugs" then her name is Jezebel Harrison."

"What would you say if I told you she had an identical twin." Lestrade demanded.

"That you clearly have too much time on your hands if you are trying to catch me out with such inane nonsense." Sherlock scoffed.

"Oh, come on," Lestrade protested. "It might be possible."

"Even putting aside the statistical unlikelihood of identical twins within the general population, every photo in this house shows only one child at a time, even if the girls were identical parents generally like to have pictures of their children together and then, of course, there's the shoes."

"The shoes?" Lestrade blinked.

"Shoes," Sherlock repeated. "There are only three sets of shoes in the hallway, mother, father and one child."

"When you two girls have quite finished," John butted in, as he sat back on his heels, having finished his examination of the child. "She has chicken pox."

"Chicken pox?" Lestrade blinked. "I don't se any spots?"

"That's because those generally start on the trunk," John lifted the edge of the little girl's top up to show the rash developing on her tummy. "She's probably been feeling out of sorts for a few days already."

Sherlock said nothing at all as he watched John climb to his feet and cross the hallway into the small cloakroom under the stairs, running the water until it was hot and carefully washing the fronts and backs of his hands and in between his fingers and down his wrists in the manner of a doctor, before wiping them dry with some toilet paper and flushing that down the loo.

"Chicken pox is contagious." He realised.

"Yeah, she'll probably be infectious for another five or six days," John allowed, as he walked back into the lounge. He looked at Lestrade. "The father will need to stay home from work and keep her out of nursery until the spots are all crusted over. You should probably let anyone who has been in contact with her know, just to be on the safe side. Chances are most of them will have had had it, in which case the risk of them being infected is pretty low but they can still pass it to their kids."

"Like I didn't have enough to deal with," Lestrade sighed. "Any chance you're solved actually the crime whilst you['re here.?"

"Mrs Harrison has been having an affair with Thomas Simpson the son and heir of the proprietor of the painting business for the last month," Sherlock supplied. "As it is clearly not creditable that she left the house without leaving a trace he was doubtless culpable in her disappearance. I suggest you arrest him and then pop round to his residence. No doubt you will find Mrs Harrison there alive and well."

"You think she abandoned her daughter to shack up with her lover?" Lestrade was appalled.

"I don't think, I know," Sherlock retorted crisply, before turning on his heel. "Now, if we are done here, I do have far more pressing matters to attend to. Come along, John."

John shrugged apologetically at Lestrade, at Sherlock's abrupt tone, before following his flatmate back out into the street. Catching up with the consulting detective he watched him out of the corner of his eye as he hailed a Taxi. If John didn't know better he would almost say Sherlock almost seemed agitated.

"Since when do you have anything more pressing than a case?" He asked curious.

Sherlock said nothing in reply as he settled himself into the back seat of the taxi and stared fixedly out of the window. For a few miles he neither spoke or moved and John resigned himself to not getting any kind of answer. It was only when they were some distance from the crime scene that Sherlock suddenly broke his silence.

"I was never vaccinated against Chicken Pox."

"People generally aren't," John observed mildly. "90% of adults in the UK are pretty much immune to the virus because they've had it before. The vaccination is usually only given people with a low immune system or to healthcare workers who have never developed any immunity as a child."

"I also never had the illness as child." Sherlock rejoined.

"Ah," John realised that he had finally got to the bottom of his flatmate's uncharacteristic anxiety. "It's really not that big a deal. Having Lestrade tell people that Jezabel was infectious was just a sensible precaution."

"A precaution which wouldn't be necessary if there was nothing to worry about," Sherlock pointed out. "Therefore, it stands to reason that there is something to worry about." Sherlock shifted about rapidly in his seat.

"What are you doing?" John frowned.

"Isn't it obvious? I'm itching. I feel an itch," Sherlock pulled up his shirt sleeve to peer critically at his almost translucent arm, which he proceeded to thrust under John's nose. "Is that a spot?"

"You care about getting a rash," John realised with a glimmer of amusement. "Still, I suppose I should have expected anyone who dresses in Dolce and Gabbana, Spencer Hart and Belstaff to be at least a little vain."

"Fashion is irrelevant," Sherlock dismissed that with a superior sniff. "I simply chose clothes that are comfortable and practical. And I don't care about the symptoms I'm simply worried about the affect of the disease."

"Your argument would be a little stronger if your coat, a couple of suits and a few shirts didn't work out at more than what was a month's salary for me and I was getting shot at." John pointed out.

"It's a spot," Sherlock decided. "I'm certain of it."

"Sherlock," John batted the arm none too gently aside. "The incubation period for chicken pox is between 10 and 21 days. You only met Jezabel about twenty minutes ago."

"But I touched things," Sherlock protested. "I touched the rabbit. That means I'm infected."

"It means you might be infected," John allowed. "But you're most probably not."

He hoped the resulting silence was a good sign but he should have known better.

"It says here that Chickenpox can be a very serious illness in adults," Sherlock had pulled out his phone and was staring transfixed at the data. "It can cause problems such as brain swelling and pneumonia. I can't risk either of those."

"I don't honestly think it's possible for your brain to be any more swollen than it already is," John remarked dryly. "And pneumonia is much less likely now that you're on the nicotine patches."

"This website says it's possible to have a subclinical case of Chicken Pox," Sherlock tapped excitedly. "I might have been exposed to the virus as a child but not actually displayed any symptoms. We need to go straight to ST Bart's and take a blood sample to check my titres."

"Sherlock," John said in the most level voice he could manage. "If you don't stop googling every health related website you can find, I am going to take your phone and throw it out of the cab window."

"You wouldn't dare." Sherlock murmured, not looking up from his phone.

"Do you want to try me."

The words hung quietly in the air between them imbued with challenge. Sherlock paused fractionally, his eyes sliding sideways as he attempted to gauge exactly how serious John was. If there was one thing that Sherlock had learnt about John Watson was that he tended to be a man of his word.

"We need to stop at the supermarket." He declared instead.

"You are volunteering to go to the supermarket?" John couldn't resist. "You should have said something before. Definitely not feeling well."

"I need calamine lotion, ibuprofen, paracetamol, oatmeal .." Sherlock ignored him as he reeled off a list.

"We are not going to the Supermarket," John vetoed that. "I have a date with Sarah tonight and I will not spend the next two hours standing in Tesco's whilst you compare the skin care properties of various different types of oatmeal."

"You're going out?" Sherlock blinked at him. "Tonight?"

"I told you this morning," John reminded him. "Sarah has tickets for this charity dinner to raise funds for the local Hospital."

"But that was before I got infected!" Sherlock pointed out.

"Sherlock, for the last time .." John was close to exploding "You. Are. Not. Infected."

"Some doctor you are. You don't even care if I'm sick." Sherlock pouted.

"That's because you're not sick!" John had had enough. "If you get sick, and right now that's still a bloody big if, then I will diagnose your symptoms, I will organize your treatment, I will ensure you are properly hydrated and force nutritious food down your stupid stubborn throat. I even promise to run your oatmeal baths and put up with your constant whining, because you will be sick and I will feel sorry for you. But I am not doing all of that for the next three weeks on the off chance that you might possibly get sick!"

Having had his say, John resolutely folded his arms and half turned in his seat so, that he was facing entirely away from the consulting detective. Amidst the flickering lights of the passing shop fronts he could see Sherlock's reflection in the window looking intently at him.

"You are being unreasonably irritable, John," He observed calmly. "Are you sure, you're not getting sick?"

John resolutely ignored him and with the determination learnt under fire did not move to scratch the totally psychosomatic itch on his arm.