“Molly, answer Dr. S., please,” said Kevin gently laying a hand on her back.
Molly was still for a few more seconds, then she nodded and said in a voice that was cracking, “Yes. Well, maybe not all of them. I let him visit with the ones I thought were his friends. I’m so sorry!” Suddenly the tears began to flow out of her eyes and she quickly wiped them away.
Sarah crossed her arms tightly over her chest. If Molly had taken the mouse home and then brought it back, it could have carried any number of pathogens with it back and forth. That might explain the purple dots in the brain cell slides. Or it might not. There was still no telling what those dots were.
“Tell me, Molly, when did this happen?”
“I took him home, let’s see, we were in exam time…”
“I remember,” said Kevin, “I had a paper to write.”
“You knew that she took a mouse home from the vivarium and you didn’t report it?” asked Sarah, turning to Kevin.
“I’m sorry,” said Kevin, breaking eye contact and blushing.
“He didn’t know, Dr. S., I promise. I didn’t tell anyone,” said Molly.
“I… I think I did know,” said Kevin quietly.
Sarah watched as Molly turned to face Kevin. Her young eyes were wide and she looked like she was seeing a stranger.
“I saw you tuck it into your backpack in the locker room,” said Kevin, meeting Molly’s eyes.
Molly looked incredulous. “But, I thought… you were with Tammy and I didn’t think…”
“I knew that the mouse was healthy and he was going to be destroyed, so I thought it wouldn’t matter,” said Kevin, looking down at his own lap. “I’m really sorry too, Dr. S,” he said.
“And did you know that she had brought it back to the vivarium for a little visit?”
Kevin swallowed and blinked. Sarah noticed his long dark eyelashes. He was a handsome kid.
“No. It never occurred to me that that could happen. I… well, I guess I should have made it clear that that would never be allowed,” he said softly, looking at Molly.
Sarah sighed. She was not a parent, but she remembered being young and sometimes making decisions that she would later regret. “Well, once you start breaking rules, it’s sometimes hard to know when to stop,” she said.
She looked at the two of them for another moment. They had made a mistake, but it was clear that they had done it out of kindness, and she really couldn’t hold that against either one of them. She remembered feeling sorry for the mice too when she had first worked with them, and, she had to admit, she had also considered rescuing one or two at some point, though she had never gone so far as to actually formulate a plan and act on it. No, this was not the time for blame.
“Tell me, when did you bring Opus back for a visit, Molly?” she said in a kinder voice.
Molly turned toward Sarah. She had stopped crying but she looked like she might begin again at any moment. “It was about five weeks ago.”
Sarah nodded. “All right then. Thank you, both of you, for coming clean about all of this. Is there anything else you need to tell me?”
Molly shook her head.
“And it was just that one mouse for that one night?”
“Yes, ma’am. But I did have him visit with pretty much all of the mice,” she said. “I wasn’t sure which ones were more his friends and I didn’t want him to miss out.”
“All of the mice in all of the rooms?” asked Sarah.
Molly shook her head, glancing sidelong at Kevin. “No, just in the room I work in most of the time. Just in C12. I was afraid I might get caught if I went into any other room. Plus I didn’t know if Opus even knew any of the other mice.”
“And you’re sure you got the right mouse back now?”
“Yes, ma’am.”
Sarah nodded, digesting the news. Then she sighed and looked at Molly. “Well, I’m not sure if it is important or not, but it’s good that you told us. The timing of that little social visit is certainly… intriguing. We will look into all of this a bit more. Does Kevin know how to reach you, if we have more questions?”
Molly blushed, and wiping a few stray tears from her eyes, she nodded and apologized again.
CHAPTER 18
The next morning, Sarah met with Tally, whom she noticed was wearing her dark blonde hair loose today, though she had the hair band around her wrist, ready to tie it back up at a moment’s notice.
Drew joined them, carrying some printouts in his hand. “We’ve got the results back from the mouse tissue analysis,” he said, handing her the papers. “You were right to suspect a foreigner.”
Sarah nodded. Ever since she had found out about Opus’s visit, she had been convinced that the purple dots were indicative of an infection, but Molly had said that her mouse at home continued to look and act healthy. She had even volunteered to bring him back, though Sarah had quickly refused her offer. Still, the fact that the mouse was healthy made for an unusual set of circumstances to be sure.
“What did you find? Bacteria? Some rogue Staph infection making cysts?” she asked as she inspected the papers. Staphylococcus aureus, a type of bacteria that commonly inhabited the skin surface, was usually referred to as an ‘opportunist’. As long as the body’s defense systems were in place, it stayed where it was, living quietly on the skin and doing no harm. However, if the skin was injured, and bacteria had a chance to enter the body, it could wreak havoc in the form of a massive, sometimes fatal infection.
As the body fought the intruder, it would typically build a wall or a cyst around the bacteria in order to isolate it from the rest of the body. For the last several years, strains of Staph had developed a resistance to antibiotics, and that made them particularly dangerous. Often they resided in hospitals, where they could attack people whose immune systems were already weak.
“No, actually, it’s a different organism, but not really one I’ve seen before. The closest I can figure is that it is a member of the Toxoplasmosis family,” said Tally.
“A eukaryote?” asked Sarah, puzzled. All living organisms are divided in two groups, Sarah had often recited to her classes: the prokaryotes and the eukaryotes. Bacteria were prokaryotes, beings so small and so simple that they didn’t even have a nucleus and lacked many of the cellular organelles, the machinery which made cells work.
All non-bacterial living beings, from single-celled organisms like yeast or amebas, to worms, plants, fish and reptiles and all the way up to human cells, were eukaryotes. This was an important distinction because the medicines used to fight an infection caused by bacteria, antibiotics, could not be used on eukaryotic cell infections. Infections caused by eukaryotes, such as malaria, were much more difficult to fight as their cells were more similar to human cells. This meant that medicines that would poison them would more likely poison people as well.
If the mice possessed a eukaryotic infection then there was no hope of curing them. They would have to be sacrificed and the study would have to be begun from scratch.
“Toxoplasmosis,” repeated Sarah, thinking back to her pathology classes. “I thought that it was only cats that got that?”
“Yes, well, we did a brief check of the literature, and you’re right, Toxoplasmosis is often associated with cats, but it can infect many different mammals. Cats are the main host, but it has been known to also reside in mice, rats, humans, and other mammals. What we don’t know is how the mice could have contracted it in the first place.”
Sarah snapped her fingers as an idea suddenly occurred to her. “Molly!” she said. She jumped to her feet, meaning to run out of the lab, but was immediately and keenly aware of her ankle. She made it to the nearest table and had to lean heavily on it.