Pandemic

Haldane clicked a button in his hand. The sterile electron microscope's image disappeared, replaced by a blood-spattered female cadaver whose eyes were blacked out by a solitary bar. Without comment Haldane tapped the button again. A human lung sat perched on a steel gurney. Another click. The screen sprang to life. A pair of gloved hands grasped the lung. One hand steadied the lung, while the other sliced into it with a scalpel. Bloody fluid spurted out as if a wineskin had been slashed open.

As he let his students absorb the images of an anonymous pathologist dissecting the pus- and blood-filled lung, Haldane wondered how lecturers in the age before Power Point and multi-media managed to make any impact. "Four days before the video was shot, this lung belonged to a perfectly healthy forty-two-year-old nurse…" He clicked the button and the black and white viral crystal reappeared. "Then she breathed in a few particles of SARS-associated coronavirus.

"Like all self-respecting coronaviruses, he has an affinity for the human nasal mucosa. He easily penetrates the epithelial barrier and replicates inside the mucosal cells." The scientific sketches on the screen changed in rhythm with Haldane's explanation. "That's when the body's armed forces, the immune system, mobilizes. Think of the phagocytes and neutrophils as the infantry in this battle. Doing the dirty work — the cell-to-cell combat. While the lymphocytes are more like the artillery, lobbing their ammo, in this case viral-specific antibodies, from afar.

"With most other coronaviruses this isn't exactly a level battlefield. Kind of like Luxembourg invading the U.S. Most of the damage comes from friendly fire-namely, the patient's own immune system, not the virus, producing the muscle aches, fever, and runny green sputum. After a couple of days the viral invader is inevitably wiped out."

The SARS virus reappeared on screen. "But this guy is tougher. In a significant percentage of cases he moves past the nasal mucosa and down the trachea into the pulmonary tissue. There he crosses the alveolar membranes of the lungs." He flashed up the images of the blood-filled lungs being slashed open again. "Resulting in a diffuse pneumonitis. And, as seen in this video, often pulmonary edema. In five percent of SARS cases, despite maximal therapy, the patient dies."

Pens throughout the auditorium flew to keep pace.

"But for those of you who consider SARS one of the horsemen of the Apocalypse, think again. It has killed less than a thousand people since its inception. In infectious disease terms that's as devastating as a fart into a head-wind." He shook his head. "Or looking at it another way, a thousand dead isn't even a global day's work for malaria, HIV, or cholera to name but a few." He slashed through the image of the viral particle with his laser pointer. "SARS-ASSOCIATED coronavirus is nothing more than a cold virus with attitude."

Haldane dropped the pointer on the lectern and stepped away. He walked across the floor until he stood a few feet from the students in the front row. "I was as scared as the next guy — no — way, way more scared when SARS first broke. After all, this bug was targeting health-care professionals. Clearly not playing by the rules. And I witnessed firsthand the havoc the little bastard could wreak." He shook his head. "But in the long run SARS has been good for us."

He scanned the quizzical young faces in the audience, allowing a few more seconds of confusion before expanding. "SARS put global infectious disease control measures to the test. And guess what? Not one country came up smelling like a rose. In fact, most stunk. Take Canada. Despite boasting one of the world's best health care systems, my colleagues in Toronto didn't react fast enough to the first case of SARS. And the city ended up paying dearly for it." Haldane pointed at the audience. "But at least now the world has been warned. We have the chance to fine-tune — in some cases revamp completely — our public health measures. In that sense, SARS was a good dry run for the real McCoy."

Haldane clicked a button and the screen filled with a grainy black-and-white still, depicting an old hospital ward packed so tightly that the stretchers touched. It was difficult to tell whether the patients (some of whom were doubled up on stretchers) were alive or dead. If alive, none were well.

Haldane stretched his hand out to the screen. "Ladies and gentlemen, meet the real McCoy."

Fall of 1918. As World War I is winding down, something even worse is sweeping through the battlefields, military hospitals, and cities of Western Europe." Haldane stepped back to the podium. "The Spanish Flu," he said with his back to the audience. "And in the soldiers returning home following the armistice of November eleventh, this virus found the perfect vector for global dissemination."

More old snapshots of hospitals and morgues. More black and white devastation.