The Threat That Knows No Boundaries
By Bryan Walsh Monday, Dec. 06, 2004

When the Spanish flu struck the world in 1918, one leading physician, a former president of the American Medical Association, thought he was seeing the end of civilization. It was a reasonable conclusion. The virus rampaged throughout the world, leaving morgues overstuffed with bodies. In 1917, the year before the flu hit, life expectancy in the U.S. was 51 years. In 1918, it was 39 years—a drop that was due almost entirely to the flu. Worldwide, 100 million or more may have died from the Spanish flu, including 20 million in India alone. And with avian influenza, it could happen all over again.

Bird flu has already killed 32 of the 44 people infected in Asia this year, and the news isn't getting better. Fortunately the only way the disease seems to spread to humans is through close contact with infected birds, although rare cases of human-to-human transmission have occurred. But if bird flu mutates and gains the ability to transmit as easily as normal flu—and scientists say that is a real possibility—it could trigger a worldwide pandemic similar to that in 1918. That prospect was raised last week, when Dr. Shigeru Omi, the World Health Organization's (WHO) regional director for the Western Pacific, estimated that such a pandemic could infect 25-30% of the world's population and kill up to 100 million people. Omi's number is higher than earlier estimates, but even in the best-case scenarios millions might die. That would make SARS, which cost Asia billions in 2003 and virtually shut down the region for weeks, look like a slight case of the sniffles.


What is being done to defend us against that fate? Far too little. Work on the one tool that can make the biggest difference in the severity of a pandemic—an effective vaccine—has been underfunded. Thanks to a new technique called reverse genetics, researchers were able to create a vaccine strain from the H5N1 virus in record time—yet the candidate vaccine is just now entering clinical trials, because drug companies have been loathe to invest in a vaccine that may never be used, and governments have been reluctant to fully fund the work. The vaccine won't be ready for five or six months, well after the high-risk winter flu season, and it would take even longer to produce enough to vaccinate a significant part of the world's population. Tamiflu, the one drug that seems to be effective against bird flu, is in perilously short supply. In a pandemic, doctors in much of the world could do little more than watch their patients die.

That's assuming they weren't sick themselves. If the bird-flu virus spread at the rate Omi estimated, nearly a third of the world's population could become ill. That means a third of the world's police officers, government officials, soldiers, technicians—and medical workers—could be knocked out for weeks. Even the temporary loss of such a large part of the work force could lead to severe disruptions of public services—and complicate efforts to fight the pandemic. Countries and businesses need contingency plans in place now, yet in Asia only Japan has any real pandemic scheme. The poor Southeast Asian countries that will be the world's front line against bird flu are almost totally unprepared. They will suffer first, and they will suffer the most.

That's why preparations for a bird-flu pandemic need to be truly international, with wealthy developed countries leading the way. They need to budget real money now to stockpile bird-flu vaccine and antiviral drugs—and allow the WHO to channel some of those supplies to countries that can't afford them. In the long run, Asia's age-old backyard-farming practices—whereby animals and human beings live in close proximity, giving rise to new viruses like H5N1—need to be moved toward modern methods of slaughtering and food preparation. That will take resources that nations like Vietnam don't have, so again, those funds need to come from developed countries. In turn, Asian countries need to be fully open and cooperative about allowing disease surveillance and scientific studies within their borders—and to invest in their public-health systems. We've come a long way since the secrecy of SARS, but too many countries still act as if an infectious disease is a source of shame that has to be kept inside its boundaries. But like the weather, infectious disease doesn't respect international borders.

Seven million dead, or 50 million, or 100 million. The estimates thrown around are so high and the disease itself so seemingly hard to treat that there's a temptation to hope it all just goes away. Rarely have so many brilliant scientists so fervently wished to be proven wrong. But a flu pandemic is inevitable, today or some time in the future. Unlike in 1918, national leaders have the experience and the science to prepare the world. They should do so.

http://www.time.com/time/magazine/article/0,9171,880311,00.html





Swine Flu: Don't Blame the Pig
By Jeffrey Kluger Wednesday, Apr. 29, 2009

Pity the poor pig. The otherwise estimable mammal has never had a very good rep — something about the mud, the snout, the oink. Now add the flu.

The swine flu outbreak that has sparked widespread fear — so much so that Egypt has ordered the slaughter of the country's 300,000 pigs, even though no cases have been reported there — is easy to pin on the eponymous animal from which it emerged, but the fact is, the current epidemic is little more than an accident of evolution. If pigs are to blame, so too are birds and humans.

The problem begins with the wily nature of the influenza virus itself. It may be an uncomplicated thing, made up of nothing more than 10 proteins assembled into a genome that's simple even by microbiological standards, but that bare-bones genome is unusually flexible, with snap-in, snap-out gene segments that allow easy mutation and exchange of information with other viruses. That's the reason we need a new flu vaccine every year: by the time one flu season has ended and the next one begins, the virus has changed so much, it can simply shake off last year's shot. Compare that with, say, polio; the vaccine was perfected in 1955 and hasn't had to change much since.

What keeps the flu relatively in check is that there simply aren't that many species that are susceptible to it — with humans, pigs and certain kinds of birds leading the list. "There are surface markers on the cells of some species that bind with sites on the flu virus," says Dr. Peter Daszak, an emerging-disease ecologist and president of the Wildlife Trust. "The influenza virus evolved along with pigs, and it did the same with a few other mammals and with birds."

The adaptability of the virus, however, made it a certainty that a strain that evolved in one of the susceptible species would easily make whatever changes were necessary to allow it to survive in one of the few other eligible hosts. So quickly and efficiently does the virus transform itself that it may require just a single passage through a single individual to get that shape-shifting job done. "Different viruses from different sources enter a cell, and the virus that comes out the other end is an entirely different one," says Dr. Richard Webby, an infectious-disease specialist at St. Jude Children's Research Hospital in Memphis and the director of the hospital's World Health Organization collaborating center. "The process is called reassortment."

Birds are the natural reservoirs of the common flu strains that strike in winter — and those strains reassort themselves to hit humans particularly hard. But while humans are not susceptible to every strain of avian flu, pigs definitely are. When bird flu viruses replicate in pigs, they pick up the viral machinery that gives more selective flu strains the power to spread to other mammals, like us. That's what makes pigs such potent mixing bowls for flu. The roundabout bird-pig-human route may be less common than the straight bird-human jump, but it may be more problematic. Strains of avian flu, like the much-feared H5N1, can infect individual humans, but they can't make the person-to-person leap. Avian flu that is passed through the pig's mammalian system, however, can be passed readily among humans.

All of this made the flu virus a tenacious foe from the outset, but once humans invented farming and learned to cultivate animals, we made a bad situation much worse. All at once, chickens, ducks and pigs — which never had much to do with one another — began living cheek to jowl in high numbers and often unsanitary conditions. Farm families and people working in live markets then began mingling with the critters. That's a pathogenic speed blender, and the viruses have taken full advantage of it. "It's really an ecological issue," says Daszak.

So if we can't fairly blame the pigs (indeed, the CDC has officially stopped calling the virus "swine flu," opting instead for the more hog-friendly 2009 H1N1 flu), can we blame Mexico? That charge doesn't stick either. Decades ago, numerous countries came together to develop the Global Influenza Surveillance Network (GISN), which allows epidemiological teams to spot new flu viruses as soon as they emerge and get vaccines ready in time. But the GISN only tracks human flu, meaning animal flu can slip by undetected. What's more, pigs that carry influenza tend not to die en masse the way flocks of birds do, eliminating the immediate tip-off that a serious pathogen is at large. None of that is Mexico's fault either. In fact, since human tourists and domesticated animals cross into Mexico all the time, there's every reason to believe that the progenitor virus behind the epidemic hitched a ride in one of them.

"I'm of the opinion that this doesn't have to be a Mexico-originated virus," says Daszak. "Somehow it got to Mexico and then mixed with humans."

If we have to pin the rap somewhere then, forget any one species or country and blame simple biology. But regardless of whence the virus came, the more salient question is, Where will it go? That's what concerns doctors as they work to stem the epidemic and make sure healthy people stay that way.

http://www.time.com/time/health/article/0,8599,1894703,00.html

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Top 5 Swine Flu Don't
By Bryan Walsh

The global rise in swine flu has showed few signs of slowing. Now in 11 countries, the H1N1 flu virus was confirmed on Thursday in the Netherlands and Switzerland; in Canada, cases rose to 27 and in the U.S., the caseload increased to 109 in 11 states, with hundreds of school closures that sent some 160,000 students home. Meanwhile, the World Health Organization (WHO) has said that a new flu pandemic is imminent, yet some pharmacies (in New York City at least) are temporarily running short of the antiviral Tamiflu. So, no one would blame you for feeling scared about getting sick.

With the cable news networks reporting nonstop on swine flu, it feels like the disease is lurking everywhere, and that your slightest sniffle is a sign that you've contracted the virus. That would explain why people with no outward symptoms of illness are flooding emergency rooms in swine flu–affected states, afraid that they might be sick. That's a really bad idea.

First of all, having to examine people who aren't really sick only stresses the already strained resources of hospitals that are trying to prepare for a pandemic. Plus, going to an emergency room unnecessarily may even pose a slight risk to you. In past outbreaks, including SARS in 2003, hospitals were actually loci of infections — all those sick people in close proximity — and the same could be true of swine flu.

If you actually have flu-like symptoms — a fever above 100° F, headache, sore throat, body aches, chills or fatigue — and you live in an area where there have been confirmed swine flu cases, by all means report to your doctor. Otherwise, leave the hospital to the sick people.

2. Don't Be Afraid to Eat Pork

On April 29, the CDC announced that swine flu would no longer be referred to as swine flu, but as the "2009 H1N1 flu." It's less catchy, but more accurate. For one thing, there is no evidence that this virus makes pigs really sick. And the H1N1 virus actually contains genes from swine, avian and human flus. The virus also cannot be spread through pork products — you can't contract swine flu by eating bacon, hot dogs or anything else that was once a pig. Nor will culling pigs, as authorities did in Egypt, do anything to stem the spread of the disease. H1N1 has jumped to humans and is passing easily from person to person, so it's now a human flu that needs to be controlled in us, not the pigs.

3. Don't Hoard Antivirals

The H1N1 virus has so far proven vulnerable to the antiviral drugs Tamiflu and Relenza, which is good news. A cornerstone of the government's pandemic preparations was the stockpiling of 50 million doses of those drugs over the past few years, enough to ensure that doctors would be able to respond sufficiently to new outbreaks. But that capacity could be compromised if people begin stockpiling antivirals for their own use. Already there are reports of pharmacies running short of Tamiflu, and many hospitals in the U.S. have begun restricting the power to prescribe antivirals to just a few doctors. Also, the misuse or overuse of Tamiflu or Relenza by patients can promote resistance in the flu virus — effectively removing the only bullets from our gun.

4. Don't Leave Home If You Feel Sick

In the absence of a vaccine, the only defenses we have against the spread of H1N1 are simple ones. Cover your mouth when you sneeze or cough (with your arm, not your hands, to avoid spreading the virus through handshakes) and wash your hands frequently. Buy a pocket-sized bottle of hand sanitizer and use it — it's the easiest way to avoid getting sick.

But when it comes to slowing the overall spread of a pandemic flu, the best thing we can do is keep sick people away from everyone else. It's called "social distancing," and studies of the deadly 1918 Spanish flu showed that cities that instituted distancing measures quickly suffered lower death tolls than cities that did nothing or reacted slowly. So if you're feeling sick, don't go to work until you feel better — even though that may not be the most welcome advice for the nearly 50% of private-sector workers in the U.S. who don't get paid sick days.

5. Don't Panic












TV anchors can't stop asking the question: "When is it time to start panicking?" How about never? Panic can only lead to stupid actions — on a personal and national level — that would likely make a pandemic worse.

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