I steadied my breathing and, surveying the scene, satisfied myself that everything would seem natural.

As I backed toward the door, the moonlight shone across her face at a low angle, filling the hollows and depressions with deep shadows. Her eyes, still open, glittered from the bottom of gaunt sockets. Despite my knowing better, I could have sworn they watched me every step of the way.

Three months later

Dr. Earl Garnet sensed it the instant he stepped inside the marbled front entrance.

St. Paul 's Hospital buzzed with a palpable nervousness and excitement unlike the feel of any other morning.

July 1.

Changeover day.

All over North America flocks of freshly minted medical graduates wearing crisp white coats streamed into their respective teaching hospitals, ready to begin the arduous residencies that would forge them into physicians.

And more staff doctors showed up at 7:00 a.m. than at any other time of the year. Ostensibly they'd come to welcome their charges, but he knew their early arrival had more to do with protecting patients from the newcomers and scrutinizing the latest batch of future healers for early signs of who would bear watching. Earl found himself exchanging pleasantries and brushing shoulders with colleagues he hadn't seen in months.

Except this July 1 would be like none St. Paul 's had ever experienced before.

He lined up to be screened for fever alongside the rest of the employees. With four tables working, the crowd moved through quickly today. Nurses already dressed in OR gowns, shoe covers, surgical hats, goggles, gloves, and tight-fitting thick masks greeted him. One applied a thermal strip to his forehead: normal. Another asked a few quick questions that he and everyone else now knew by heart, and he just as quickly rattled off the answers: no cold symptoms, no foreign travel, no unprotected contact with suspect or probable cases. That done, he received a dated stamp on his hand, the kind that discos and theme parks use- except instead of opening the doors to fun-filled entertainment, it granted him admission to his own ER for another day on the job. He moved on to the next stop, where similarly attired porters dispensed a complete set of protective gear to every single person entering the hospital.

Welcome to the "new normal" of SARS in America.

Severe acute respiratory syndrome, the scientists had named it the year it first appeared in China. At the time residents took to calling it SCARES.

An electron microscope mug shot of the suspected cause, a smudged-looking sphere surrounded by a ring of tiny balls, had made the front pages of newspapers all over the world. The crownlike appearance allowed it to be recognized as a member of the coronavirus family, a microbe with many different strains, some responsible for up to 30 percent of common colds in people, but most infected only the lungs and bowels of livestock, such as chickens, pigs, or cows. Yet somehow one of these latter strains had acquired a genetic makeover and jumped the species barrier to take on humans in a deadly new way. Similar events with other organisms had given rise to some of our most lethal diseases- the so-called swine flu of 1918 is thought to have come from pigs, AIDS from monkeys, avian influenza from chickens. Humans, having never had prior exposure, lack immunity to these invaders, so the prospect of a brand-new bug that's highly contagious always grabs the scientific world's attention.

The real kicker is that researchers couldn't isolate the coronavirus from over half the cases, which left the possibility that this disease might be a multiheaded monster that attacked its victims in ways not yet understood, or that some other completely different unknown, a deadly X, could be floating around out there killing people.

That first year the outbreaks were beaten back. But just when the world thought itself safe, the organism mutated, the new vaccines against it were suddenly obsolete, and pockets of infections began to crop up again. Even then, until a few months ago, it had been largely the problem of other countries, the few cases that occurred in the United States being relatively mild. Everything changed after a busload of tourists returning from a religious meeting in Toronto, Canada, center stage for the initial North American endemic and center stage for its reappearance, brought back more than a few Mountie souvenirs.

According to the latest count, there were 169 confirmed cases admitted to designated Buffalo hospitals, 31 of them under treatment at St. Paul 's, and most of them health care workers.

In the first wave of infections among hospital staff, two nurses and a doctor died. After that, there'd been no containing it. People broke quarantine, others lied about having symptoms or where they'd been, and while the number of new cases leveled off in the community, the virus continued to strike doctors, nurses, orderlies, and residents all over the city. Even now, every few days at St. Paul 's someone with a fever would be pulled out of line at the screening station to be put in isolation for observation. Most turned out to have nothing more than a cold, but with a 15 percent mortality rate, no cure, and some survivors left so short of breath they could barely walk across a room, fear had become the norm for those who treated the sick.

Fortunately, no one who'd gone through with Earl this morning got tagged. After suiting up, they broke into smaller groups and hurried off to their respective departments.

"Heads up, guys."

"Eyes sharp."

"And cast-iron stomachs all around."

Their parting banter reminded Earl of soldiers moving out on patrol.

Upstairs, the nurses would be adopting an edgy alertness as well, scanning their wards the way ship captains keep a lookout at sea, always ready for trouble. If a rookie went alone into a patient's room, they'd keep tabs on him or her. When a novice wrote a medication order, they'd double- and triple-check it for mistakes. And during any attempt by a first-timer to perform a procedure, they'd hover over the event with the anxious scrutiny of spinster chaperones. They also would set their radars to home in on any of last year's junior trainees who might stride through the corridors a little too cockily, lording it over those who'd replaced them on the bottom level of the teaching pyramid. Arrogance could kill as readily as inexperience, and the two together were even more lethal; no one could pop them both faster than veteran nurses. Their weapon of choice: sidle up to any offender who showed off to the newfound underlings and say, "So, you finally brought me someone on the floors who actually knows less than you do. Remember, honey, that ain't saying much."

The result of it all?

Already anxious patients clutched their blankets and hoped for the best every time a new masked face with youthful eyes came near them. And they soon learned the surest way to spot a beginner: even under the surgical gowns all the clinical manuals and packets of cue cards these kids invariably kept stuffed in their pockets made telltale bulges. Earl sometimes fantasized these junior doctors pulling no end of things out from under them- suture kits, crutches, their lunch- like Harpo Marx in OR gear.

He tried not to smile as another throng filed by. The bulges of this bunch stuck out like tumors, indicating pockets laden well past the bursting point. Through the backs of their badly tied outfits he spotted their short white clinical jackets, trademark for the lowest of the low.

Medical students.

Their rapid-fire chatter, typical of first-day jitters, bounced off the walls.

u… orientation's in the basement auditorium…"

"… but where do we meet our chief residents…"