“Something’s coming at us,” says Bruce Gellin, MD. “And we don’t know what it is.”

Dr. Gellin, head of the federal government’s vaccination program, is facing the greatest challenge of his career. It’s his job to coordinate the biggest vaccine effort ever, against a threat whose magnitude is still unclear, using a vaccine that has only just been created and whose side effects are still being identified.

But Dr. Gellin, a graying infectious-disease specialist with a youthful insouciance, seems remarkably calm about it. “Anxious isn’t a word that comes out of his lips,” says his wife, Sharon, a nurse. “He’s more likely to say, ‘This will be interesting.’ ”

Swine flu blasted its way into public consciousness last spring — only to disappear from headlines for weeks at a time as health-care reform and its angry protesters took center stage. But behind the scenes, a vast team of doctors and scientists have been working nonstop, ignoring trivial matters like the need for sleep and, in some cases, personal catastrophe. They’ve accomplished remarkable things: Within a few months of the April discovery that a new pathogen was spreading fast through humans, scientists had identified all of the virus’s genes. Public health experts and policymakers had decided, first, that a vaccine ought to be made and then that it ought to be used. And manufacturers had begun producing tens of millions of doses and started testing them on volunteers. All without knowing just what to expect come fall and winter, when the flu typically intensifies.

“We didn’t have a crystal ball,” says Dr. Gellin. “You have to recognize that there are unknowns, but you have to make decisions.”

For months, his Black­Berry has been going off at all hours, with calls and messages from colleagues in Australia, Europe, and Atlanta, where the Centers for Disease Control and Prevention is headquartered. Everyone is wrestling with the same concerns:

  • Will the vaccine arrive in time? Grown in fertilized chicken eggs, like all flu vaccines, this one is yielding only about a third as many doses per egg as usual. The aim is to inoculate as many as 160 million Americans, but far fewer doses may be ready by the end of October, by which time sniffling children may well be quickly spreading the disease.
  • If the vaccine is ready, will the public accept it? Swine flu set off alarm bells in April because it was completely unfamiliar — researchers eventually realized it contains genes from swine, bird, and human flu viruses — and because it hit Mexico hard enough to shut down its capital. But many Americans now think of the virus as mild. And people tend to be suspicious about vaccines, especially those recommended for kids and pregnant women. Up to 20 percent of all pregnancies are naturally cut short by miscarriage, so some women will no doubt miscarry after being vaccinated. Will people blame these and other problems on the vaccine?

“This pandemic is a chance to strengthen our vaccination program — or really set it back,” Dr. Gellin says.

The Race Begins

The pandemic started innocuously enough. In April, the CDC got a report from Navy researchers that a child in the San Diego area had been infected with an unknown virus. A viral sample was bounced up a chain of laboratories to the CDC, where it was identified as swine flu. “We didn’t think that much about it at first,” recalls Nancy Cox, PhD, who heads the CDC’s flu division. It was normal to get an occasional report of humans stricken with swine flu. But the cases almost invariably occur in people who live on farms with pigs or who have recently encountered them at, say, a state fair. None of that described this boy.

“We thought, Hmm, this is interesting. But that was all,” Dr. Cox says.

Almost simultaneously, the Navy researchers picked up what looked like another infection, this one in a nine-year-old girl from Brawley, California, near the Mexican border. She hadn’t had contact with pigs either.

Even as the California cases were identified, a mysterious epidemic was exploding in the sprawling metropolis of Mexico City. “For a month, we had 35 to 50 people with respiratory symptoms every day in our emergency room. One day, we had 200,” says Javier Romo-Garcia, MD, of the National Institute for Respiratory Diseases in a southern district of the city. “It was really tough.”

The two story lines came together during a spring storm on the night of April 23. Mexican health officials had sent their patients’ viral samples to the CDC, and now Dr. Cox was on the phone with colleagues in Mexico City. As the lab equipment spit out the viral analyses, she read the results. They were identical to the ones she’d seen a few days earlier, she realized: The virus killing Mexicans was the same one that had infected children in California. A new and lethal virus was on the loose. “Jesus Christ, Jesus Christ,” whispered a scientist as the news was relayed.

But that wasn’t the night’s only shock. “When I finished the call, my cell phone rang again,” Dr. Cox says. “It was my daughter. I thought she and my husband were just upset because I wasn’t home for dinner, but lightning had struck our house.”

Dr. Cox ran home as soon as she could, but there was nothing to be done. She and her family watched as their home of 20 years went up in flames.

By the next morning, she was taking conference calls in clothes that still smelled of smoke. “It was devastating,” she says. “But I flipped a switch in my mind to concentrate on what we thought might turn into a pandemic.”

Doing What It Takes

Public health agencies had been preparing for this moment for years. The SARS epidemic in 2003 had woken officials to the way a spreading illness can wreak havoc on economies and people’s daily lives. And the flu had long ago proved its catastrophic power. The Spanish flu of 1918-1919, considered the worst pandemic in recorded history, killed an estimated 50 million people worldwide. So Dr. Cox’s flu team, along with other public health workers, had stockpiled anti­viral drugs and updated outposts with superfast detection kits, including the one that flagged the first U.S. case in San Diego. They’d run drills for various what-if scenarios. Now it was all happening for real.

Soon it became apparent that swine flu was no more lethal than the typical seasonal flu. Yet no one is ready to say for sure that we’ve dodged the bullet — and no one is calling off the massive vaccination campaign. Why? Because scientists know it’s foolish to try to predict the direction of a flu pandemic. In fact, researchers have a saying, notes Michael Shaw, PhD, who heads the CDC flu lab under Dr. Cox: “If you’ve seen one pandemic … you’ve seen one pandemic.”

The most dire scenario involves not just swine flu but the H5N1 bird flu or avian flu virus that’s been smoldering in Asia since 1997 — it’s fatal in nearly two thirds of cases. Its spread has been limited by the fact that it can’t leap easily from person to person. But an animal simultaneously infected with swine and bird flu could act as a living mixing bowl; the viruses could swap genes to create a superbug as deadly as bird flu and as easily spread as swine flu. Fortunately, that isn’t likely, but a flu virus needn’t trade genes to get more dangerous. The virus responsible for the 1918 pandemic caused only mild disease at first but evolved in ways that made it able to quickly kill previously healthy people.

So the government has committed to paying nearly $2 billion for vaccines. It’s an enormous investment, but the only alternative is to do nothing and hope for the best. Public health experts know that there are other good uses for those billions, but even if the virus remains no more dangerous than the typical seasonal flu, it will kill thousands of Americans. And privately, vaccine experts see another substantial benefit from the swine flu campaign: It will strengthen a vaccine pipeline that’s badly in need of help.

Vaccines have always been a step­child of the pharmaceutical industry. They generally aren’t big money earners, because just one or two doses protect people, unlike medicine for problems like diabetes, which must be taken daily. And while people clamor for drugs that will cure their ailments, they often don’t bother with vaccines — until, that is, a serious epidemic approaches.

But the massive cash infusion will help convince drug companies that vaccines are a reasonable gamble. The complex logistical preparations will serve as a dry run for future efforts. And that’s good, because someday, experts know, we will face a truly calamitous virus. And when we do, we’ll be grateful for the ability to protect ourselves with a vaccine.

Reader's Digest
Originally Published in Reader's Digest