A deadly virus sweeps through towns across the globe, wiping out millions of people in days. Victims suffer from high fever. They're left gasping for air. It sounds like a plot from a Stephen King novel.
The problem is that this isn't fiction, neither past nor present.
It happened in 1918 when an especially virulent strain of influenza spread throughout the world. World health experts fear another influenza pandemic could happen again soon.
They worry that the avian flu virus that has been spreading throughout Asia and now Europe could mutate and spread easily from person to person. If so, it could trigger a pandemic that could kill millions.
The avian flu virus, known as H5N1, has public health experts running scared. Although the H5N1 virus has not yet become efficient at infecting people, experts say the conditions are ripe for the virus to mutate--as viruses constantly do--and become a human disease.
Once the virus becomes able to spread easily among people, it would not stay confined to a particular location for very long. Nowadays, millions of people cross international borders every day, and an infectious disease is just a few frequent-flyer miles away.
Experts are also troubled because the H5N1 virus bears striking similarities to the deadly 1918 virus, sometimes known as the Spanish flu or H1N1.
Perhaps, most troubling of all is that experts know pandemics happen. Experts say they don't know whether H5N1 will be the virus to cause the next pandemic. But they know pandemics happen.
In the last 300 years, there have been 10 pandemics. In the last 100 years, there have been three. The influenza pandemic of 1918 was a deadly plague that killed between 50 million and 100 million people.
It was followed by two milder influenza pandemics, one in 1957, caused by the virus known as the Asian flu, and one in 1968, caused by the virus known as the Hong Kong flu.
Experts estimate that in the next influenza pandemic, 20 percent to 60 percent of the world's population would become infected. In a mild pandemic, there could be an estimated 2 million to 7.5 million deaths. In a severe pandemic, like the 1918 flu, there could be 180 million to 360 million deaths worldwide.
As of mid-March, an estimated 184 people have been infected with H5N1 and 103 have died from it, according to the World Health Organization.
In a sign of just how concerned experts are, the WHO recently warned that the world was "closer to another influenza pandemic than at any time since 1968."
No one knows when the next pandemic will strike. The WHO categorizes pandemic risk into six stages. At stage 1, there are no new influenza subtypes circulating in humans. Stage 6 is a full-fledged pandemic. The WHO has categorized the current risk from H5N1 as stage 3, which means there are isolated human infections with a new subtype, but no, or very limited, human-to-human spread of the disease.
If the virus does mutate and become easily transmissible, it would probably sweep through local communities for a six- to eight-week period, but it could come in waves that last as long as a year or more.
Others doubt the public health sector's concerns. Skeptics believe the scaremongering has reached fever pitch.
They note that so far the virus has infected relatively few people and has remained essentially a bird disease. And even though viruses mutate, so far H5N1 has not been able to figure out how to spread efficiently among people. Perhaps it never will.
Instead, critics point to a "Chicken Little" culture whipping the public into a frenzy about a bogus health threat. Cell phones causing brain cancer, mad cow disease, Alar in apples, SARS, Ebola or Y2K come to mind.
Precedents for false alarms abound. In 1976, an influenza outbreak at Fort Dix, N.J., triggered concerns that a major flu pandemic was imminent. The federal government launched a campaign to vaccinate all Americans to prevent deaths on the scale of the 1918 pandemic. When insurance companies refused to provide coverage to the vaccine manufacturers, the government agreed to accept liability for claims, ostensibly related to the outbreak.
The pandemic never materialized. But the government ended up facing millions of dollars in lawsuits from plaintiffs who claimed that they came down with Guillain-Barre syndrome as a result of the vaccine.
Author Michael Fumento, who specializes in science and health issues, believes there is a tendency for some people to hype the threat of a pandemic and for the media to seek out the most alarmist experts.
"What we can say with confidence is that there is never such a thing as helpful hysteria," he writes. "And the line between informing the public and starting a panic is being crossed every day now by politicians, public health officials and journalists."
Fumento's article, "Fuss and Feathers: Pandemic Panic Over the Avian Flu," appeared in the November issue of the Weekly Standard.
"There probably will be another pandemic, but nobody knows when or what its origin will be," he writes. "We do know that with every month that passes, we'll be better prepared. Unless the current panic, having failed to materialize, makes us overly complacent. That's a real possibility.
"In 1976, swine flu went from 'next pandemic' to laugh line on 'Saturday Night Live' in record time. And as for those anointed experts, public health officials and reporters whose wall calendars always read '1918'--it's time to buy a new one," he writes.
Health experts, however, are caught in a proverbial Catch-22.
"Anything we say in advance of a pandemic sounds alarmist, any preparation we make after a pandemic starts is clearly inadequate," says Michael Leavitt, the secretary of the Department of Health and Human Services, who was a speaker at the Business Planning for Pandemic Influenza conference organized by the Centers for Infectious Disease Research and Policy at the University of Minnesota in February.
If they warn about a potential threat that doesn't happen, officials are accused of scaremongering. But if they fail to properly warn and prepare the public, then they could be on the firing line with federal commissions investigating after the fact why they failed and what went wrong.
"There are those who paint anyone who talks about influenza as Chicken Little," says Dr. Michael Osterholm, the director of CIDRAP.
"And then there are those who claim, 'You are not telling it straight--we are all going to die,'" he says. "Neither is the truth. Those two positions are the easy positions because it means you have to do nothing when, in fact, the truth is in the middle and requires that you do something."
Sometimes, of course, catastrophic predictions do come true. For years, experts had warned that New Orleans could flood if the city were hit by a powerful hurricane. Last year, Hurricane Katrina slammed into the city.
One of the lessons learned from Hurricane Katrina is that "the unthinkable happens, and we need to be thinking about the unthinkable," Leavitt says.
The trouble is it can be very hard to predict exactly when a catastrophe will take place--experts can only try to read the signs.
Any discussion of avian flu needs to distinguish between a pandemic flu and the seasonal flu. Every year, thousands of people get sick with a seasonal flu. They may run a fever and have aches and pains, but most people recover. Those most at risk are small children and the elderly, those with weak immune systems. Every year, about 36,000 people in the United States die from the seasonal flu, according to the Centers for Disease Control and Prevention.
But because a pandemic flu is a new type of virus, people have no immunity to it. As a result, more people become sick. Depending on the virulence of the strain, many more die.
Once a pandemic strain has been around, it continues to mutate and becomes less virulent. More people begin to build up immunity to it. It becomes a much less deadly disease.
All human influenza viruses, however, get their start as avian flu viruses that mutated.
Viruses can mutate gradually, or they can do it in one leap, Osterholm says. Sometimes a person or an animal, such as a pig, may be infected with both an avian influenza and a human influenza. That gives the viruses the opportunity to swap genes.
Other times, the avian virus gains the ability through mutations to be transmitted to humans while retaining its essential avian properties. So now it is not a half-bird, half-human virus, it is a bird virus capable of human-to-human transmission.
Because there are so many people, pigs and chickens in China and they all live cheek by beak so to speak, it is an ideal breeding ground for influenza viruses, experts say. China's population has grown from 790 million in 1968 to 1.3 billion in 2004.
The number of pigs has increased from 5 million in 1968 to 508 million. Poultry has increased from 12 million in 1968 to 15 billion.
"It's a genetic roulette table," Osterholm says of China. "And the more throws of the dice or the balls, the greater the chance you are going to land on the wrong number," he says.
Once the virus has mutated into a strain that can pass easily from one person to the next, it would not take long for it to spread around the world. It would be tough to keep the virus from spreading.
That's what happened with the SARS outbreak in 2003. The virus originally began infecting people in China.
Then it turned up in Toronto after an elderly woman got on a plane in Hong Kong bound for Toronto where she lived with her son.
She died. Her son became sick and went to the hospital where he was put in a room with another patient. Soon a visitor to the roommate became sick and then the roommate as well.
Experts see troubling parallels between the H5N1 virus and the deadly 1918 H1N1 virus.
Research has shown, for instance, that the H1N1 virus jumped from an avian species to humans through mutation, so that it retained the essential properties of the original avian virus.
"A number of the same changes have been found in the H5N1 viruses and are feared to be the precursor of a new pandemic," Osterholm says.
In addition to that, the H5N1 virus seems to be targeting people who are in the prime of life, just like the 1918 H1N1 virus.
The people most vulnerable to influenza viruses are usually the very young and the very old.
But the 1918 virus triggered something known as a cytokine storm--or a deadly overwhelming overreaction of the victim's immune system.
People who had the strongest immune systems, therefore, were among the most likely to die from the disease.
Scientists are troubled because history appears to be repeating itself. Most of the people who have died from the H5N1 virus are children and people under the age of 40.
Both H1N1 and H5N1 have the same protein tag, and it is this protein that blocks interferon production and creates the cytokine storm, Osterholm says.
"H5N1 and the 1918 H1N1 are kissing cousins of the highest order," Osterholm says.
Now, efforts are focused on trying to develop a vaccine that would be effective for the H5N1 virus and on trying to increase production of the antiviral Tamiflu.
Scientists, however, are unable to develop the right vaccine until the virus mutates into the human strain. And once they have the virus, it would take months before a vaccine could be produced.
Antivirals like Tamiflu may help lessen the severity of the disease, but it is not clear just how well Tamiflu will work on the mutant strain. And even so, there might not be enough to go around.
The WHO has been discussing a strategy to try to contain an outbreak of H5N1 among people by using a "fire blanket" of antiviral drugs given to everyone in the area around an infection outbreak.
Experts don't know whether the H5N1 virus will be the one to set off the next influenza pandemic.
"The reality is this (pandemic) will happen at some point in time," Leavitt says. "We don't know if the H5N1 virus will be, in fact, the spark that creates the next global pandemic.
"But we are a generation that has, in fact, been warned."
PATRICIA VOWINKEL lives in New Jersey.
April 15, 2006
Copyright 2006© LRP Publications