A killer race

by Liza on Oct. 10th, 2005
in Life Science

145

comments

It's in the news. People are dying from a relative of the 1918 Influenza virus half a world away, and scientists fear it may be the next pandemic. Sounds like science fiction, or the latest box-office smash, right? Unfortunately, it's real, and is happening right now.

chickens: (Photo courtesy Laura Hadden)

In Southeast Asia, a virus known as avian influenza or avian flu has the potential to spread and kill humans with terrifying speed. Avian flu is also known as H5N1 for the proteins that bind, infect, and destroy its host cell to thrive. Chickens can die within hours of exposure, swollen and hemorrhaging, but it is just as lethal to mammals from lab mice to tigers. The virus has decimated bird flocks in 11 countries mostly in Asia, and has killed 62 people (half the known cases) to date, with highest fatalities occurring in Vietnam, Cambodia, and Thailand. So far, nearly all people infected contracted the sickness directly from infected poultry and at this point there is no confirmed evidence of efficient human-to-human transmission. However, health authorities fear that the H5N1 strain will likely mutate into a pathogen easily passed between humans if it continues to persist in the environment. If that happens, and authorities believe it's only a matter of time, the world could face a catastrophic pandemic.

Many health organizations and governments are stockpiling a drug (Tamiflu) to protect against this potential pandemic, but scientists are reporting that a strain of H5N1 avian flu virus is showing resistance to the antiviral drug. Scientists are working to avoid this disaster by detecting changes in the evolving H5N1 virus. As a first step, scientists have rebuilt the 1918 flu-a disease that killed as many as 50 million people-from pieces of genetic material retrieved from the lungs of people who died 87 years ago. Gene-swapping experiments are starting to give scientists some clues in the lab. When small substitutions were made, the reconstructed virus could no longer replicate in the lungs of mice, kill animals, or attach itself to human lung cells.

So far H5N1 has not yet learned the trick of racing from person to person like the ordinary flu and maybe never will. Nevertheless, experts fear that the risk could materialize and are urging the world to prepare for the worst.

United Nations Food and Agriculture Program

NPR Health and Science Report

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Your Comments, Thoughts, Questions, Ideas

Liza says:

Outbreaks of disease in poultry flocks in Turkey and Romania have experts fearing that H5N1 bird flu has reached Europe. But scientists don't yet know for sure whether or not the disease in these two outbreaks is, in fact, even avian flu, much less the strain that everyone is worried about.

Aside from the obvious threat to domestic poultry flocks, virologists are afraid that the H5N1 flu will mutate from its current form, in which the virus is transmitted from birds to people, to a new, scary form in which the virus jumps from person to person directly.

posted on Mon, 10/10/2005 - 4:01pm

Blood Sugar Sex magik! says:

I dont want to DIE!!

posted on Sun, 06/18/2006 - 4:36pm

Liza says:

The outbreaks of avian flu in Romania and Turkey were caused by avian flu, and new cases have been found in Greece.

Some countries are starting to stockpile Tamiflu, the antiviral drug that may help people infected with the flu. But at least one human case of the bird flu has proved resistant to Tamiflu. Another drug that may be useful is an antiviral called Relenza.

Antivirals aren't vaccines; they don't keep people from getting sick in the first place, but they can help keep the virus from replicating itself so explosively. Antivirals will be useful in the early stages of any outbreak, as it will take time to create and distribute a vaccine and for people to develop immunity.

A drug manufacturer in India has announced that it will be making a generic version of Tamiflu, in spite of the fact that the drug is still protected by a patent. (The Indian generic drug will not be sold in the West.)

posted on Tue, 10/18/2005 - 10:29pm

Liza says:

The US FDA is discussing the safety of Tamiflu use by children after reports of 12 deaths in Japan. (Tamiflu has been widely prescribed and used in Japan for influenza cases.)

The FDA notes, however, that they don't have enough information to prove that Tamiflu caused the deaths. The fatalities could have been caused by encephalopathy, a complication of influenza itself.

posted on Fri, 11/18/2005 - 3:09pm

Liza says:

Preliminary tests detected the H5N1 strain of bird flu in samples from an area south of Moscow where hundreds of birds died suddenly.

The Chinese government reports that 2,600 birds have been found dead of the same strain of bird flu in the Inner Mongolia region.

Officials also said that they fear an outbreak in Macedonia, where a large number of birds have died.

And the risk of bird flu spreading to the Middle East and Africa, carried by migratory birds, has grown with the confirmation of the Turkish and Romanian outbreaks.

Despite the bird deaths, the European Center for Disease Prevention and Control is downplaying fears of the H5N1 flu spreading to humans. They told people not to touch dead birds, and to only eat well-cooked eggs or poultry. Zsuzsanna Jakob, head of the agency, said:

"The risk of infection for most people in Europe is close to zero....If they follow these guidelines, the risk is basically nonexistent."

Officials at the agency are planning to hold a simulation exercise of a flu pandemic by the end of the year to improve their preparedness.

And the World Health Organization is recommending that governments stockpile enough antiviral drugs to treat 25% of their populations.

posted on Wed, 10/19/2005 - 2:15pm

Liza says:

Scientists fear that migrating birds from Europe and Asia carrying the H5N1 virus will arrive in Africa's Rift Valley (Ethiopia, Kenya, and Tanzania) between December and early spring.

Because of the lack of money and scientific infrastructure in those countries, the virus could easily become widespread in the environment and on farms before it's detected. And because people in this area live in close proximity with animals, there's a very real possibility that the human influenza virus and the avian flu could mix, perhaps giving the avian virus the ability to spread easily from person to person.

Once outbreaks of avian flu were discovered in Asia and Europe, authorities killed millions of birds in attempts to stop the spread of the disease. But in Africa, a family's chickens often aren't a commercial product but a crucial source of protein. Officials warn that poor farmers may not report dead birds for fear of losing their chickens. Or they might slaughter birds (to eat them or to sell them in local markets) before public health workers can examine them. (Eating cooked birds isn't dangerous, but touching infected birds before they're cooked could infect humans.) And, of course, taking sick birds or their bodies to markets could infect other birds, spreading the animal disease and making a human one more likely.

The United Nations says it will help countries in Africa step up their surveillance to try and prevent epidemiologists' worst-case scenario.

posted on Fri, 10/21/2005 - 3:01pm

Liza says:

On Saturday, officials in Croatia slaughtered thousands of domestic birds and disinfected a large area near where six swans were found dead of avian flu.
Russian authorities reported a new outbreak.
Sweden confirmed a case of avian flu.

posted on Sun, 10/23/2005 - 5:24pm

Liza says:

China reported four more bird flu outbreaks in Liaoning province in the last two weeks. Experts fear that counterfeit vaccines are being sold in the province, and that millions of birds haven't been properly protected against the virus. (Yes, a vaccine is available for birds. Why isn't a vaccine available yet for people? Read this.)

posted on Mon, 11/14/2005 - 2:35pm

Gene says:

Bird flu is real, and a potential catastrophe. But will it be a worldwide pandemic? At least one doctor says no.

Dr. Patrick Cunningham, an Assistant Professor of Medicine at the University of Chicago, argues "there will never be another 1918." Many factors contributed to the mass fatalaties of that outbreak--poor sanitation, crowded living conditions, generally poorer health and nutrition, etc. These factors have been greatly reduced, at least in the West.

Make no mistake--bird flu is a serious threat, especially in underdeveloped parts of the world. But Dr. Cunningham believes it is unlikely to match the flu of 1918, at least here in the US.

posted on Wed, 10/19/2005 - 5:46pm

Joe says:

The conditions for a serious flu outbreak still exist in many parts of the world where a pandemic is most likely to originate. I find shrugging off the potential seriousness of this strain of virus because it may infect and possibly kill fewer people in the US than in the rest of the world to be a bit ruthless. Are our lives more valuable than those in other countries?

posted on Thu, 10/20/2005 - 12:42pm

Gene says:

I don't believe Dr. Cunningham is shrugging off anything. He recognizes the serious threat posed by avian flu. However, that threat is not equal in all parts of the world. We in the US probably have less to worry about. (Note: that's less to worry about, not nothing to worry about.) Working the public into a panic is not a good thing. Focusing attention and resources on places that are more vulnerable, is.

posted on Thu, 10/20/2005 - 2:25pm

Greg says:

It is true that the fatality rate would be much less in America than undeveloped areas of the world. According to Mike Osterhome, disease researcher, we could loose 1-2% of our population (still in millions). While that death rate is nothing to snuff at, the major problem will be in how the population reacts w/ mass hysteria and our country shutting down to the point where basic services are threatened. That is why it is so important to plan now!

posted on Tue, 08/08/2006 - 9:06pm

Liza says:

Cunningham says,

"Flu hits the elderly the hardest, but the "elderly" today are healthier, stronger, and better nourished than ever before."

But the aspect of the 1918 flu that many doctors and scientists found so puzzling and scary was that the virus hit the very young and the very old, as expected, but also took out a surprising number of healthy adults in their prime. (The mortality plot of the 1918 flu looks like a "W", with peaks at the ends and in the middle.)

He's probably right, in some ways. Some virologists think that the 1918 outbreak began in the giant, crowded camps set up to train soldiers for World War II, and traveled around the world with the soldiers. There isn't a mass mobilization of that scale anywhere in the world today. Many people who didn't die of viral pneumonia later developed bacterial pneumonia; in 1918 there were no antibiotics, but obviously we have very good ones today. And SOME people probably are less crowded, better nourished, and have better access to medicine. But not everyone. And, as is the case with many infectious diseases, the threat to the least fortunate is a threat to all of us.

posted on Fri, 10/21/2005 - 3:24pm

Liza says:

I've been reading John M. Barry's The Great Influenza: The Epic Story of the Deadliest Plague in History. This passage (from page 239) addressed part of my discomfort with Gene/Cunningham's position:

"Influenza almost always selects the weakest in a society to kill, the very young and the very old. It kills opportunistically, like a bully. It almost always allows the most vigorous, the most healthy, to escape, including young adults as a group. Pneumonia [a common complication of influenza] was even known as "the old man's friend" for killing particularly the elderly, and doing so in a relatively painless and peaceful fashion that even allowed time to say good-bye.

There was no such grace about influenza in 1918. It killed the young and strong. Studies worldwide all found the same thing. Young adults, the healthiest and strongest part of the population, were the most likely to die. Those with the most to live for--the robust, the fit, the hearty, the ones raising young sons and daughters--those were the ones who died.

In South African cities, those between the ages of twenty and forty accounted for 60 percent of the deaths. In Chicago the deaths among those aged twenty to forty almost quintupled deaths of those aged forty-one to sixty. A Swiss physician 'saw no severe case in anyone over 50.' In the 'registration area' of the United States--those states and cities that kept reliable statistics--breaking the population into five-year increments, the single greatest number of deaths occurred in men and women aged twenty-five to twenty-nine, the second-greatest number in those aged thirty to thirty-four, the third-greatest in those aged twenty to twenty-four. And more people died in each of those five-year groups than the total deaths among all those over age sixty.

So the next question is WHY did the 1918 flu kill so many young and healthy people? Read on...

posted on Mon, 10/24/2005 - 11:33am

Liza says:

WHY did the 1918 flu kill so many young and healthy people?

Again, I'm relying on John M. Barry's The Great Influenza: The Epic Story of the Deadliest Plague in History, this time from pages 246 and 247:

"Victims' lungs were being ripped apart as a result of, in effect, collateral damage from the attack of the immune system on the virus."

Enzymes in saliva that destroy some microbes are the body's first defense. Any pathogens that the enzymes don't destroy have to get past nasal hairs that filter out large particles, and mucus that lines breathing passageways and traps organisms and irritants. Cells underneath the mucus layer have cilia--little fans, beating 1,000 to 1,500 times a minute--that sweep microbes up into the larynx. And if a microbe does manage to gain a foothold, the body tries to flush it out with fluids--a runny nose--or with coughs and sneezes.

Two kinds of white blood cells patrol the respiratory system, seeking and destroying all invaders. More enzymes directly attack bacteria and viruses or block them from attaching to tissue beneath the mucus. White blood cells also produce interferon, which can help to block infection by viruses.

"All these defenses work so well that the lungs themselves, although directly exposed to outside air, are normally sterile.

But when the lungs do become infected, other defenses, lethal and violent defenses, come into play. For the immune system is at its core a killing machine. It targets infecting organisms, attacks with a complex arsenal of weapons--some of them savage weapons--and neutralizes or kills the invader.

The balance, however, between kill and overkill, response and overresponse, is a delicate one. The immune system can behave like a SWAT team that kills the hostage along with the hostage taker, or the army that destroys the village to save it.

In 1918 especially, this question of balance played a crucial role in the war between virus and immune system, and between life and death. The virus was often so efficient at invading the lungs that the immune system had to mount a massive response to it. What was killing young adults a few days after the first symptom was not the virus. The killer was the massive immune response itself."

From page 250:

"In 1918 the immune systems of young adults mounted massive immune responses to the virus. That immune response filled the lungs with fluid and debris, making it impossible for the exchange of oxygen to take place. The immune response killed."

posted on Mon, 10/24/2005 - 11:41am

Liza says:

Early results suggest that the H5N1 avian flu also causes people's immune systems to overreact.

posted on Mon, 11/14/2005 - 2:27pm

Liza says:

If the H5N1 avian flu is really as deadly in humans as it seems to be right now, it's because the virus triggers a massive immune response that can damage the lungs and cause death. (These findings are based on a study of 26 patients in Viet Nam--18 victims of H5N1 avian flu and 8 victims of regular influenza.)

posted on Mon, 09/11/2006 - 2:17pm

Liza says:

Mice infected with the reconstructed 1918 flu virus experience "an overblown inflammatory response" that can cause serious lung damage and death.

Scary news, yes, but it also offers a new avenue for research: if scientist can target the patient's immune response to the virus, as well as the virus itself, they'll have two weapons against pandemic flu.

posted on Wed, 09/27/2006 - 4:18pm

Liza says:

More evidence that 1918 flu and H5N1 avian influenza cause an overblown immune response...

posted on Wed, 01/17/2007 - 5:56pm

Liza says:

Was an overactive immune response the only killer?

Nope.

The battle between the virus and the immune system destroyed the cells under the mucus with the cilia. Without the sweeping action of the cilia,

"...the normal bacterial flora of the mouth [had] unimpeded entry into the lungs. Recent research also suggests that the neuraminidase on the influenza virus makes it easier for some bacteria to attach to lung tissue, creating a lethal synergy between the virus and these bacteria, And in the lungs, the bacteria began to grow.

Bacterial pneumonias developed a week, two weeks, three weeks after someone came down with influenza, including even a seemingly mild case of influenza. Often influenza victims seemed to recover, even returned to work, then suddenly collapsed again with bacterial pneumonia."

(Barry, page 251)

posted on Mon, 10/24/2005 - 11:49am

Liza says:

But modern drugs have leveled the playing field, right?

Hard to say, actually.

A 1957 flu pandemic

"...struck in the golden age of antibiotics, but even then just 25 percent of the fatalities had viral pneumonia only; three-quarters of the deaths came from complications, generally bacterial pneumonia. Since then bacterial resistance has become a major problem in medicine. Today the mortality rate for a bacterial pneumonia following influenza is still roughly 7 percent, and in some parts of the United States, 35 percent of pneumococcal infections are resistant to the antibiotic of choice. When staphylococcus aureus, a bacterium that has become particularly troubling in hospitals because of its resistance to antibiotics, is the secondary invader, the death rate-today-rises to as high as 42 percent. That is higher than the general death rate from bacterial pneumonias in 1918."

(Barry, p. 252)

Not exactly reassuring.

What about antivirals?

There are two that could work against the avian flu. Tamiflu, the first-line drug, is being stockpiled all around the world. But it takes a while to make and right now there isn't enough of it to treat the victims that epidemiologists predict should the avian flu make the jump to human-to-human transmission. Also, there's evidence that a strain of the H5N1 avian flu virus is showing resistance to Tamiflu. A second antiviral drug, Relenza, is also being produced.

posted on Mon, 10/24/2005 - 11:59am

Liza says:

A new study shows that none of the treatments used for SARS patients did much good, and some of them might actually have been harmful. (Those treatments included most of the retroviral drugs, including the ones being stockpiled for use against a possible H5N1 avian flu pandemic.) SARS, or Sudden Acute Respiratory Syndrome, is caused by a coronavirus that hadn't been previously seen in people; it may have made a species jump via live exotic animals sold for food. It spread quickly via airline travel and within hospitals.

The study gives a clear picture of how tough it is to be on the front lines of the battle against newly emerging infectious diseases...

posted on Tue, 09/12/2006 - 9:20pm

Liza says:

As of October 21, the H5N1 virus has killed 67 people; 44 in Vietnam, 13 in Thailand, six in Indonesia and four in Cambodia. Almost all of the victims had close contact with birds or had eaten improperly cooked poultry or eggs. There are a few cases where epidemiologists aren't sure how the victims got sick.

In Thailand, a mother died of the H5N1 virus last year after caring for her dying daughter, who also had the disease. And this week possible cases of avian flu among family members in Indonesia sparked fears that the virus had developed a much-feared mutation that would allow it to spread easily from person to person.

But the World Health Organization says "not so fast!" The virus may, in fact, just be spreading via the close contact normal in families.

Stay tuned...

posted on Fri, 10/21/2005 - 2:08pm

Liza says:

WHO officials discovered that the victims of avian flu in Indonesia all had exposure to infected poultry, and they're ruling out human-to-human transmission for now.

posted on Mon, 10/24/2005 - 12:26pm

Liza says:

China has reported at least one confirmed human death due to avian flu--a 24-year-old farmer from the eastern province of Anhui.

In Hunan province, a 9-year-old boy has recovered from H5N1 flu. His 12-year-old sister, who died in October, is suspected of having had the virus, but samples aren't available to prove it.

posted on Fri, 11/18/2005 - 2:16pm

Liza says:

MSNBSC has a cool slideshow called "Bird Flu Around the World".

posted on Fri, 10/21/2005 - 2:12pm

Liza says:

The virus that's currently circulating--the one that we can study and make a vaccine against--infects humans by way of birds. It won't cause a pandemic in people. To do that, it will have to mutate. And any vaccine made against the bird virus might not work against the new human one. Still, a few drug companies are tackling the problem, hoping that a vaccine against the current virus will provide at least partial protection if and when the virus mutates.

posted on Mon, 10/24/2005 - 12:43pm

Liza says:

Read this transcript of NPR's Health Editor, Joe Neel, talking about the status of influenza treatments and vaccines.

posted on Tue, 03/14/2006 - 4:16pm

Liza says:

Scientists in China are trying to use H5N1 antibodies from horses to treat avian influenza in people. (This method of illness-prevention is called passive immunotherapy.)

Vaccines are in development, but they're all experimental, and don't yet target a human H5N1 virus. And there are only a few drug treatments for people who catch avian influenza.

But antibodies from horses protected lab mice known to be vulnerable to the avian flu. The scientists say their treatment,

"...may potentially be used for the early treatment of avian influenza patients to reduce the severity of illness and the likelihood of H5N1 transmission to others."

Though this is definitely good news, it's not quite as rosy as it sounds. The experiments were done on dog kidney cells and lab mice, and there's a lot more work to do before anyone can say this treatment is safe and effective in people. Also, the horse antibodies can cause a strong immune response called "serum sickness" in people treated with them. But careful purification of the antibodies can help reduce the risk.

posted on Wed, 03/29/2006 - 2:30pm

Liza says:

Could you use the chicken vaccine on people?

That's what New York Times reporter Donald G. McNeil asked in his article, "Turning to Chickens in Fight with Bird Flu."

The answer, in short, is either "no" or "only in the direst of situations."

Why?
The chicken and human vaccines start out the same way--workers inject the virus into fertilized eggs to multiply as the embryo grows. After being extracted from the egg, the virus is killed (often with ultraviolet light), then concentrated and mixed with an agent that causes a heightened immune response.

But the chicken vaccine isn't filtered and purified to remove bits of bacteria or other viruses. And they usually contain the whole virus, not just the part needed to prime the body's immune system. And the purification part is the expensive part.

The "booster" agent in chicken vaccines is mineral oil, which does cause a strong immune reaction, but can also cause inflammation and abcesses. Chicken vaccines are weaker--chickens are small, and market chickens only need to be protected for 6 weeks.

Chicken vaccines may not work in people at all. And they may cause nasty side effects.

So, in the event of a pandemic, doctors will have to weigh the risks of using the chicken vaccines against the risk of doing nothing at all.

posted on Wed, 05/03/2006 - 1:55pm

Liza says:

Avian influenza is a concern, but the sky isn't falling.

Here's Newsweek's take on why avian flu shouldn't be compared to the 1918 virus.

posted on Mon, 10/24/2005 - 12:54pm

Anonymous says:

I think that this attement is copletly right! It is a disease, we all know, but it isn't the end of the world!

posted on Thu, 12/29/2005 - 5:19pm

Liza says:

Dr. Abigail Zuger wrote an editorial for The New York Times suggesting that our collective freaking out about distant and hypothetical health risks (like avian flu) frees us from having to worry about our immediate and real ones--risks caused by our unwillingness to face reality or change our behavior.

posted on Tue, 10/25/2005 - 9:52am

Joe says:

An article in the November issue of Scientific American thoroughly covered the possible implications of an influenza pandemic.

posted on Tue, 10/25/2005 - 3:05pm

Liza says:

Check out the BBC's "flu tracker."

posted on Wed, 10/26/2005 - 1:26pm

Liza says:

Know what those letters and numbers (H5N1) mean?

Influenza strains are classified according to two proteins on the surface of the virus--hemagglutinin and neuraminidase. (Hemagglutinin allows the virus to bond to the cell that's being infected. Neuraminidase allows newly created viruses to escape from infected cells.) Our immune systems make antibodies against these two proteins, or antigens.

There are 16 subtypes of hemagglutinin proteins, three (H1, H2, H3) associated with epidemics in people. And there are nine subtypes of neuraminidase proteins, two (N1, N2) associated with epidemics in people.

The influenza virus experiences antigenic shift--where the virus gradually mutates over time to evade the immune system--and antigenic drift--where two different strains of influenza combine to form a new subtype with a mixture of the surface antigens of the two original viral strains.

Huh? Say that part about the antigenic shift again?

When two different strains of influenza infect the same cell at the same time, their protein capsids and lipid envelopes are removed, exposing their RNA, which is then transcribed to DNA. The infected cell then produces new viruses that combine antigens; for example, H3N2 and H5N1 can form H5N2 this way. Because our immune systems have trouble recognizing new influenza strains, they can be highly dangerous. Influenza viruses that "shifted" caused the Asian Flu pandemic of 1957, the Hong Kong Flu pandemic of 1968, and the Swine Flu scare of 1976, and the infamous Spanish Flu outbreak of 1918 that killed millions of people worldwide.

posted on Wed, 10/26/2005 - 2:16pm

Liza says:

The vast majority of human avian flu victims are people who had close contact with poultry. And scientists have found the virus in bird droppings, blood, etc., so that makes sense. The bigger mystery, though, is why some people get sick and others don't. Lots and lots of people work in the bird markets of Asia, surrounded by secretions that could be contaminated with the flu virus, and only a very small number of those folks have become ill.

posted on Fri, 10/28/2005 - 1:32pm

Liza says:

Scientists in Japan and the Netherlands published part of the answer in today's issue of Nature and this week's Science. Their research shows that the cells that the avian flu virus binds to are clustered deep in human lungs, while the cells that human flu binds to are in our upper respiratory tracts. That means that avian flu is unlikely to spread by coughs and sneezes, and in order to become a pandemic strain,the virus may have to undergo more mutations than previously thought.

posted on Thu, 03/23/2006 - 5:14pm

Liza says:

A recent news item about an avian flu outbreak in Canada got me thinking: is avian flu here in Minnesota?

Turns out that birds in North America, especially turkeys and waterfowl, experience some strain of avian flu almost every year. And Minnesota, which is the nation's top producer of turkeys, has had some cases of avian flu every year since 1979 (except for 1997). The outbreaks have involved 1,100 flocks of turkeys.

But Minnesota has an avian flu monitoring and control program, and past bouts of bird flu have convinced most poultry producers to move their turkeys and chickens indoors, where they're protected from diseases spread by migratory birds.

None of the Minnesota outbreaks has involved the H5N1 strain of avian influenza that has been headline news lately. Officials in Canada are testing sick ducks and should know which strain of avian influenza they're dealing with as early as today.

posted on Wed, 11/02/2005 - 10:31pm

Liza says:

Here's more about how the US poultry industry is dealing with the threat of H5N1 avian flu.

posted on Mon, 11/14/2005 - 2:24pm

Liza says:

Scientists at Seoul National University in South Korea gave an extract of kimchi, a spicy Korean version of sauerkraut, to 13 chickens infected with avian influenza. A week later, 11 of the chickens started to recover.

Is sauerkraut a magic bullet against the disease? Who knows? A sample of 13 chickens isn't much to work with, and a lot more research needs to be done before a claim like that can be substantiated.

But several TV and radio stations have picked up the story, and one major sauerkraut distributor has seen an 850% spike in sales!

Should sauerkraut have any preventative effect, and should a pandemic develop, Twin Citians will be in good shape: there are at least 115,000 tons of the stuff in Wisconsin alone.

posted on Mon, 11/07/2005 - 10:34pm

Liza says:

Here's more on the sauerkraut story...

posted on Wed, 11/16/2005 - 10:58am

Liza says:

Anyone have any thoughts about how fears of an avian flu pandemic compare to the 1976 swine flu scare?

posted on Thu, 11/10/2005 - 12:10pm

Liza says:

Here's an interesting paper on the swine flu scare by Joel Warner: "The Sky is Falling: An Analysis of the Swine Flu Affair of 1976." He looks at whether or not the measures taken by scientists and politicians were justified, and why the vaccination program was a failure.

Another swine flu site: "1976: Fear of a great plague"

Richard Krause, of the National Institutes of Health, wrote, "The Swine Flu Episode and the Fog of Epidemics."

Washington Post staff writer David Brown wrote: A Shot in the Dark: Swine Flu's Vaccine Lessons."

posted on Mon, 02/13/2006 - 12:05pm

Liza says:

Bird flu in Vietnam is mutating.

Researchers at the Ho Chi Minh Pasteur Institute looked at 24 samples of the H5N1 virus, from both poultry and humans, and saw significant variations in the antigens on the viruses' surfaces. (Antigens are the foreign substances on the virus's envelope that stimulate the body's immune system to produce antibodies.) The changes suggest that the virus is adapting to new hosts. A post on the Institute's website says:

"There has been a mutation allowing the virus to breed effectively on mammal tissue and become highly virulent."

posted on Mon, 11/14/2005 - 2:50pm

Liza says:

British researchers are trying to create a genetically modified line of chickens that will be able to resist all strains of avian influenza.

The UK has been largely anti-GMOs (genetically modified organisms) in the past. But with the alternative being the wholesale slaughter of poultry flocks and a possible human pandemic, people might change their minds...

posted on Mon, 11/14/2005 - 5:50pm

Joe says:

In a bizarre and somewhat alarming move, Indonesia's National Institute of Health for Research and Development ordered that the biggest, most experienced and best-equipped avian influenza laboratory in the country be shut down at the end of this year. See the letter announcing the decision here.
The lab, called NAMRU-2, is run by the United States Navy in Jakarta, and participates in with the World Health Organization's surveillance for emerging diseases in Indonesia. Closing the lab could hamper detection of an outbreak of influenza. Given that a rapid response to the detection of a local influenza outbreak is key to averting a global outbreak, and given the cases of avian flu already diagnosed in Indonesia, I hope that the US and Indonesia can resolve their issues to keep this lab open.

posted on Wed, 12/14/2005 - 11:12am

Jason Shu says:

Bird flu is really deadly!

posted on Thu, 12/22/2005 - 1:40pm

Liza says:

It looks that way right now, but a closer look might reveal a different truth.

Right now, the cases that governments are reporting, and that make the news, are the ones associated with a severe illness or death. But it's possible that a lot of people have been exposed and didn't get critically ill, or even sick at all. To know for sure, you'd have to test large numbers of people for antibodies to the H5N1 virus.

Several such studies have been done in Asian countries, but the results haven't been published yet.

At least one study suggests that mild flu-like symptoms are pretty common among people who work closely with poultry. According to a MedPageToday article,

"The data are consistent with avian flu as a 'relatively mild, febrile, respiratory infection that easily can go undetected,' the researchers concluded, especially if it occurs outside the major cities where good quality health care is available. On the other hand, they noted, the data 'need to be confirmed with population-based seroprevalence studies and with virology studies in patients with acute mild infection. . . .In the absence of serological data, we cannot state the cause of disease,' they wrote. 'The observed results could have resulted from other diseases affecting poultry and humans.'"

Scientists are still trying to figure out just how dangerous and deadly this flu really is.

posted on Mon, 02/13/2006 - 12:11pm

Dralan Fang says:

this sounds like another one of those 'killer bees' threats. so im not so sure about it. im not trying to be ignorant but yeah that's what it sounds like. i mean, look at the health care we have these days.

posted on Wed, 12/28/2005 - 11:29am

Liza says:

Yes, health care has certainly improved.
And maybe the scientific establishment is overreacting, on the theory that it's better to be safe than sorry.
But read the posts near the top of this thread about exactly HOW the 1918 flu killed so many people. And read, too, the disaster preparedness plans that apply to avian flu. Sure, we have better equipment and better drugs, but those won't help us if we don't have enough respirators to breathe for all the people who need them, or the virus mutates faster than we can develop new antivirals and other drugs.

The best weapon against avian flu might be quarantine, but that's never a popular option, and it doesn't work so well if there's a period when an infected person is symptomless but still able to pass on the virus.

posted on Tue, 08/29/2006 - 9:09am

Liza says:

MedPage Today has put together a special end-of-year report, analyzing 2005's avian flu coverage. Pretty interesting.

posted on Thu, 12/29/2005 - 10:29am

Anonymous says:

what if your a vegetarian??? could you still get from other products.. not including meat???

posted on Tue, 01/03/2006 - 1:14pm

Liza says:

All the health agencies say that if the meat is properly cooked and handled, there is no risk of catching avian flu by eating poultry.

If you're a vegetarian, and you avoid contact with both domestic and wild birds (scientists think the virus is shed in their secretions), you should have no risk at all for the current avian flu.

But if the virus mutates, so that it's transmissible from person to person, then avoiding meat won't confer any protection at all.

posted on Tue, 03/28/2006 - 2:27pm

Olivia says:

When do scientists suspect bird flu will come to the u.s.?

posted on Wed, 01/04/2006 - 2:41pm

Liza says:

Scientists say it's possible that the H5N1 virus could spread to Alaska or western Canada as early as this spring. The US is expanding efforts to test migrating wild birds in an attempt to detect the virus's arrival here.

Listen to a story NPR did on this subject.

Government officials are operating under the assumption that someone will find an infected bird in the US by the fall. But as long as it's a bird disease, it's not a cause for panic.

posted on Tue, 03/14/2006 - 3:58pm

Liza says:

Another story on looking for avian flu in Alaska.

posted on Fri, 06/09/2006 - 3:00pm

Anonymous says:

What caused the bird flu?

posted on Thu, 01/12/2006 - 7:54pm

nichole says:

i think even if you are a veggie only eater you would be at the same level of risk for a strain of flu that was passed from person to person. if it comes to that.

posted on Sat, 01/14/2006 - 7:30pm

Laura says:

I do think the Avian bird flu will become an epidemic but with the new technology and new resources that we will find a cure or vaccine in the near future

posted on Sun, 01/15/2006 - 5:13pm

Liza says:

On February 15 NPR's Health Editor, Joe Neel, answered listener questions about the potential for a flu pandemic and the status of vaccines and treatments. Want to read the transcript?

Scientists are testing a vaccine against H5N1 avian flu right now. (This New York Times graphic shows how it works.) But it's a vaccine against the current avian flu. To become pandemic flu, the H5N1 virus will have to mutate, and the vaccine in development right now won't work against it.

On Monday, March 13, Health and Human Services Secretary Mike Leavitt said it will take at least six months to produce a vaccine against bird flu that has mutated to allow human-to-human transmission. Until that vaccine is available, communities will have to rely on traditional public health measures to stop the flu's spread.

posted on Tue, 03/14/2006 - 4:02pm

Anonymous says:

probably

posted on Sun, 01/15/2006 - 5:32pm

Stephanie says:

now that i learned more about it im not so worried about it anymore. but in a way i am!

posted on Sun, 01/15/2006 - 6:06pm

Ebeneezer says:

Ebeneezer Scrooge's thoughts\r\n\r\ni think the avian flu is something that everyone should know about. i am doing it for a science project

posted on Wed, 01/18/2006 - 9:59pm

Joe says:

The H5N1 bird flu virus has spread to Africa and has been confirmed in north-central Nigeria.

posted on Thu, 02/09/2006 - 9:41am

Anonymous says:

What exactly IS the bird flu? How do you catch it, and how do you cure it?

posted on Thu, 02/09/2006 - 11:15am

Liza says:

Here's the Wikipedia entry on avian flu, and the Center for Disease Control's Avian Influenza fact sheet, although there are lots of other resources already linked in the previous posts.

Scientists don't know how you catch it, although they think it may require direct contact with the virus-laden secretions of infected birds. (That may be why doctors are seeing cases among people who work with poultry, although the big mystery is why some people get sick when so many others don't.)

We also don't know how to cure it. There are two antiviral drugs that may help, if they're taken in time, but influenza is a viral disease, and those mostly just have to run their course.

posted on Mon, 02/13/2006 - 12:39pm

Anonymous says:

this isn't the only flu outbreak. there was the pig flu somes years back. we live in a fear base world. they want to sell you something based on your fear. study shows that people buy and consume more when they are scared. world govn't are increasing their gnp as we speak.

posted on Sat, 02/11/2006 - 7:08pm

Liza says:

It's true that this isn't the only flu outbreak since 1918. Read some above posts for more information on the swine flu scare of 1976.

I'm not a conspiracy theorist. I think that someone stands to gain, somehow, from just about any event, but that doesn't mean that the concern of scientists and policy makers over the H5N1 strain of avian flu is some trumped up nonsense to get people scared and buying things.

If we're lucky, the avian flu scare will end up like the swine flu scare, and we'll be able to look back and see where we were wrong and where we overreacted. But, given their incomplete understanding right now, I think that scientists are genuinely concerned.

posted on Mon, 02/13/2006 - 12:33pm

Liza says:

Avian flu hit Turkey hard, with at least 20 infections and 4 deaths (including three children from one family) as of January 20th. Thousands of birds have been slaughtered in an attempt to contain the virus. But amidst all that chaos, scientists also see opportunities to study the H5N1 virus.

The Turkish government has been very receptive to proposed avian flu research, and scientists are considering:

a detailed epidemiological study to try to determine the virus' potential for human-to-human transmission;
a study looking for antibodies among patients' families, poultry workers, health care workers, and residents in affected areas (comparing who's been infected with who has actually gotten sick will help scientists understand just how dangerous the virus really is);
and a study to figure out the risk factors for severe illness among those infected.

Why Turkey?

Well, Turkish doctors seem to take more elaborate patient histories than those in East Asia, and good case histories are important to understanding viral exposure.

Scientists are also particularly interested in the Turkish outbreak because the country experienced a large number of human cases in a short period of time. Is that because it's winter and people brought their animals inside when the weather turned bad? (In rural Turkey, lots of people live in one-room houses with their animals.) Is it because of a genetic mutation in the virus, seen also in China and Vietnam, that allows it to bind more easily to human cells?

And the disease seems to be milder in Turkey than in East Asia. (The death rate of about 25% is half that seen so far in East Asia, and there have been five mild or completely asymptomatic cases.) Are milder cases happening elsewhere and just not being recorded? Or is it because worried Turkish parents, well-versed in the symptoms of avian flu, are taking their children to hospitals right away and getting them antiviral drugs early in the course of the disease? Or are some of these milder cases actually false positives?

Researchers are hoping to tease out the answers to all of these questions.

posted on Thu, 02/16/2006 - 11:01pm

Liza says:

New cases of avian flu (in birds, not people) have been reported in:

Azerbaijan,
Egypt,
France,
Germany,
Greece,
Hungary,
Iraq,
Nigeria,
Russia, and
Slovenia.

Scientists are also testing dead birds found in Bosnia for the H5N1 virus.

That's the bad news.

The good news is that an Australian company, CSL Ltd., has tested small doses of avian flu vaccine in healthy adults and achieved "encouraging" results.

posted on Fri, 02/17/2006 - 5:24pm

Liza says:

The H5N1 flu has spread to 13 new countries in the last three weeks (including those listed in the above post), and a human case popped up in Malaysia, which had been avian flu-free for about a year.

posted on Thu, 02/23/2006 - 11:00pm

Liza says:

The Washington Post says that wild birds may be getting a bad rap when they're blamed for the spread of the H5N1 virus to Nigeria. Some scientists think it's far more likely that the virus arrived in poultry and poultry products--chickens living in giant commercial flocks, not little backyard ones. (Nigeria imports more than a million chicks each year from countries such as Turkey and China.)

posted on Fri, 02/17/2006 - 6:05pm

Buddha says:

It has now arrived in Europe - Germany, France, etc. - via wild bird migrations from Africa. Be worried? Who knows...

posted on Sat, 02/18/2006 - 12:11pm

Anonymous says:

I hope it doesn't hit the U.S.!

posted on Mon, 02/20/2006 - 1:38pm

Liza says:

The guards at the Tower of London are caring for the fortress' fabled ravens inside in an attempt to keep them safe from H5N1 flu spread by wild birds. Legend says that should the ravens ever leave the Tower, the centuries-old castle--and the British monarchy with it--will crumble.

posted on Thu, 02/23/2006 - 11:06pm

Liza says:

Swedish authorities have reported cases of H5N1 flu in wild ducks.

posted on Tue, 02/28/2006 - 5:03pm

Liza says:

The US Center for Disease Control maintains a website ("Avian Influenza: Current Situation") which is frequently updated and lists all the countries with human cases and all the countries with animal cases.

posted on Tue, 03/14/2006 - 4:56pm

Liza says:

In late February, scientists discovered H5N1 virus in a dead cat in Germany. (Read Joe's blog post about the discovery.) It was the first mammalian case of H5N1 flu in Europe. (Later stories said that three domestic cats had been found infected with the virus.)

On March 2, scientists found H5N1 virus in a weasel-like animal called a stone marten. The stone marten was found alive, but obviously ill, on the same German island as the dead cats. Researchers think the stone marten got sick the same way the cats did: by eating infected birds.

Eight other mammal species (in addition to humans, domestic cats, and stone martens) are known to be susceptible to H5N1 avian flu:

palm civet;
cynomolgus macaque;
ferret;
New Zealand white rabbit;
leopard;
tiger
rat;
and pig.

These incidents don't necessarily mean an increased risk of pandemic flu, but scientists are investigating the virus's potential to adapt to mammals (including humans).

posted on Tue, 03/14/2006 - 5:19pm

Liza says:

Ian Wilson and other scientists at The Scripps Research Institute in La Jolla, California, have identified some of the mutations the H5N1 avian flu virus will need if it's to cause a human pandemic. Specifically, they looked at a structure on the surface of all influenza viruses called hemagglutinin (the "H" in H5N1--see the previous post for more).

The researchers dissected and imaged a sample of the virus that killed a 10-year-old Vietnamese boy in 2004. This virus looks a lot like the virus that caused the 1918 epidemic. And it looks less similar to H5N1 virus taken from a duck in Singapore.

The change in the hemagglutinin structure seems to make the virus more able to bind to mammal cells, but it doesn't seem to have full virulence.

A previous study, though, suggested that only two mutations are necessary to change the bird virus into one that sickens people.

The scientists suggest that the test they used, called a glycan array, might be useful in monitoring the virus in birds and as it infects people, letting epidemiologists recognize viral mutations early on and alerting public health officials to the potential for a pandemic.

posted on Thu, 03/16/2006 - 5:07pm

Liza says:

See this post (above) -- scientists have figured out why the avian flu isn't spread easily by coughing or sneezing.

posted on Thu, 03/23/2006 - 5:19pm

Anonymous says:

will the bird flu ever reach the united states?\r\n\r\n\r\n\r\nTori Johnson\r\n\r\nMinnestoa

posted on Sat, 03/25/2006 - 5:42pm

Anonymous says:

the "bird flu" i think will be a problem, but with all of our new medical advances, i think it will be taken care of and i dont think it will get too out of control.

posted on Sun, 03/26/2006 - 7:36pm

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