Mirrors (5 page)

“Here we see the nature of the illness that developed after exposure to XK59 and the timing of onset of symptoms,” Muñoz said. “You can appreciate why, initially, we looked for viruses that cause fever and bleeding.”

“The first column implies you knew when each victim was exposed to XK59,” Shaker objected. “How could you know that?”

“You’ll see momentarily,” Muñoz replied. “For now, please observe that all victims had fever, most in the 105° Fahrenheit range.”

“Which is curious,” I said, “because none of my mice exhibited fever.”

“I was going to ask you about that,” Muñoz responded. “You monitored their temperatures?”

“Very closely.”

“But, Dr. Krispix,” McCloskey intervened, “mice and men aren’t
mirror
images, are they?”

“With regard to the development of fever, they may be,” I postulated.

Shaker nudged slightly to one side. Each move seemed to be metered and difficult, as if dictated by gears with teeth locked in arthritic rust. “But your mice may have died from bleeding before they had a chance to develop fever,” he suggested.

Muñoz stepped closer to the table. “I believe the question of fever will be answered in the next slide.”

“From a lab standpoint,” Muñoz continued, “we’ve seen anemia and elevated white blood cell counts in all victims along with the presence of XK59 in blood and tissues.” Turning more sober, he added: “And two bacteria—
Vibrio parahaemolyticus
and
Aeromonas hydrophila
—present in blood and feces.”

“In
all
victims?” Shaker volleyed.

“Yes.”

“That’s incredible!” he gasped.

“But it may explain one of the findings,” I said. “The presence of the two bacteria in the blood most likely caused fever in the victims.”

“Hold on!” Kosta protested. “Not everyone here is a microbiologist. What’s the significance of the bacteria?”

“Blood is normally sterile,” Muñoz explained, “meaning bacteria should be absent. The presence of these particular bacteria suggests a connection between the victims and the sea where both microbes reside. You’ll see that connection shortly when I identify the exposure that probably caused the XK59 poisonings.”

“
Vibrio
,” Kosta said, holding a hand up unsteadily. “It causes cholera, right?”

Muñoz propped a palm under his chin as if to reckon how much detail to divulge. “You’re thinking of
Vibrio cholerae
, one of the various species in the genus,
Vibrio
. What we’re talking about here is a cousin called
Vibrio parahaemolyticus
that also causes diarrhea and, like
Vibrio cholerae
, resides naturally in the sea.”

“Yes, and we’ve had several outbreaks of illness in the United States recently due to
Vibrio parahaemolyticus
,” Shaker volunteered, “ones following the ingestion of raw oysters.” He raised a hand as if to reserve his speaker status while he pondered something. “And if I’m not mistaken, some patients in these outbreaks experienced bloody diarrhea.”

“Correct,” Muñoz replied. “Unlike
Vibrio cholerae
, which causes exclusively watery diarrhea, infection with
Vibrio parahaemolyticus
can cause bloody or non-bloody diarrhea. Recent rises in sea temperature may have allowed
Vibrio parahaemolyticus
to multiply to unprecedented levels, and since oysters are filter feeders that concentrate bacteria in their guts, people who eat them raw can become infected.” He paused. “However, it’s unusual for
Vibrio
parahaemolyticus
to enter the bloodstream.” He pointed to the slide. “Yet here we see
all
victims had that pathogen in their blood.”

“With XK59 slicing and dicing blood vessels in the gut and elsewhere, I’m not surprised the bacteria entered their blood,” I said.

“And the second organism?” Kosta asked, sliding a pale hand forward along the table.

Muñoz approached him tenderly.

“Yes,
Aeromonas hydrophila
.” Muñoz paced along the side of the table in professorial style. “Like
Vibrio parahaemolyticus
, this bacterium is a denizen of the sea, but debate exists as to its ability to cause diarrhea in humans. If you search the literature, you will find reports that describe gastrointestinal symptoms linked to this organism in persons who consumed raw oysters.”

“Hold on!” McCloskey bellowed. “Are you saying
oysters
caused the XK59 poisonings?” He seemed affronted by the notion.

Muñoz donned a coy look. “To answer that question, we need to discuss a tool epidemiologists often use to study illness outbreaks. It’s called a ‘case-control study.’ It compares exposures among persons with the disease of interest—‘cases’—to others without the disease, or ‘controls.’ The goal of case-control studies is to identify one or more exposures reported more commonly among ill than well persons and thereby identify a likely cause of illness. During the past week, I conducted such a study by interviewing the twelve cases or their next of kin along with a group of persons without XK59 poisoning. I just completed the analysis today.”

“Who were the controls?” Shaker asked.

“Individuals in neighborhoods where the cases resided. I identified two controls for each case.”

Whispering into my ear, Flagstaff said, “He used his CDC affiliation, saying nothing about the UNIT.”

The next slide showed the dozen cases and 24 controls to be similar in age, race, ethnicity, education level, recent travel history, and presence of underlying medical conditions.

“What I did next was get a diet history from cases and controls,” Muñoz continued. “I asked cases what they ate during the week before they fell ill and controls what they ate during the week before the interview. To refresh memories, I had subjects consult a calendar. Here’s what I found.”

“As you can see from the asterisks, the only statistically significant difference was cases were more likely than controls to have eaten seafood.” He scanned the room. “Are we together?”

Heads nodded with the lone exception of McCloskey who sat stoically with a look of defiance.

“Seafood is a large category,” he said. “Did you narrow it down?”

Muñoz advanced the slide.

“
Shrimp
?” McCloskey erupted. “Are you saying
shrimp
caused the XK59 poisonings?” He raked his eyes over Muñoz as if the Peruvian were a traitor for maligning a major seafood product harvested from his home state of Louisiana.

Muñoz, feeling the heat, deferred to Bird.

“Indeed, sir,” Bird said, his voice subdued. “We obtained a sample of leftover shrimp from one of the victims and it yielded
Vibrio parahaemolyticus
,
Aeromonas hydrophila
, and XK59.”

“Was the shrimp cooked that you tested?” I asked, incredulous that XK59 was present.

“No, it was raw. It was a portion the victim had refrigerated before barbecuing the rest.”

“But cooking should have killed the bacteria,” Shaker insisted.

“And denatured XK59,” I added. “The protein is heat-sensitive.”

“That’s the problem,” Muñoz riposted. “The victim didn’t barbecue the shrimp thoroughly. Which raises a key point: All of the victims ate shrimp that was outright raw—at sushi bars, for example—or only partially cooked.”

“How much XK59 was in the shrimp you tested?” I asked Bird.

“The results are pending.”

Kosta: “I don’t understand how the shrimp became tainted with XK59 in the first place.”

“Nor do we,” Muñoz replied. “As for the bacteria, both were probably present in the shrimp to begin with since they’re marine organisms.”

Shaker sighed aloud. “The public needs to know what’s happening.” He addressed McCloskey. “And your shrimpers in Louisiana are gonna take a hit.”

“I know it, goddammit!” McCloskey shouted. “But they’re hardy folks. They’ve weathered hurricanes, oil spills, recessions, and competition from imported shrimp; they’ll survive this crisis, too.” He glowered at the slide before his expression changed. “Hang on! Am I reading things correctly? It says 92% of the cases ate shrimp. Was there one case who didn’t eat shrimp?”

“One didn’t,” Muñoz confirmed.

“How’d he get poisoned?”

“I don’t know, but his parents insist he never ate shrimp because he was allergic to it.”

“Who was the patient?” I asked, heart racing.

“The California victim, a young man from Marinero.”

Pain seared my abdomen.

“Could he have eaten shrimp accidentally while dining out?” Kosta asked.

“He rarely ate out. His food allergies led him to prepare most of what he ate.”

“So if it wasn’t shrimp that poisoned him, what did?” McCloskey repeated.

Muñoz shook his head. “Again, I don’t know. He’s what we epidemiologists call an ‘outlier’—a case distinct from the others. Such cases often provide critical clues to unsolved mysteries, so we need to interview his folks in greater detail.”

“Where are they?” I asked, voice cracking.

“Up the coast from Marinero, in Half Moon Bay.”

I felt sick to my stomach.

“And what about the shrimp the victims ate?” Shaker asked. “Did it come from a single source?”

“As far as we know,” Bird replied. “All of it came from an aquaculture firm in Ecuador. Muñoz and Krispix will be going there shortly.”

I glared at Bird. “I
can’t
go! My wife’s due date is in six days!”

Eve was a
flight attendant for Australia’s
Qantas
airlines when I met her. Our encounter occurred at the end of my first year of hematology fellowship on a flight across the Pacific after I attended a research forum in Sydney. Midway through the flight to Los Angeles, we hit a patch of turbulence. Serving drinks at the time, Eve stooped and clutched the armrest beside me.

Ill at ease, I closed my eyes and gritted. I felt a hand grasp one of mine. It belonged to Eve, and she assured me in her tender Aussie voice that all would be well. Shortly, with the return of calm, she stood and offered me a drink.

“You’re cool under pressure,” I told her.

She smiled. “That was nothing.”

She moved up the aisle but as she traversed the opposite lane with dinner trays, our eyes locked. She turned abruptly and returned aft where she conversed with a colleague before returning to my side. “Recovered?” she asked.