by Viewzone's Dan Eden
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Update: May 24, 2006
Human-To-Human Transmission Of Bird Flu Has
Been Confirmed In Indonesia (APA).
This Mutated Form Of The Virus Is The Danger Science Expected
(APA) -- The spread of the bird flu virus from human to human can claim millions of lives. According to pessimistic forecasts of the UN experts, the spread of the virus from human to human may lead to the death of at least 150 million people. Russian head sanitary inspector Gennadi Inishenko predicts 50 million and Russian Emergencies Ministry predicts 27 million might die from this virus.
The possibility of spread of the H5N1 virus from human to human was confirmed in Indonesia. The virus has been found on three children, who stayed in the same room with the infected woman.
The World Health Organization has investigated the death of six of seven members of a family, who contracted the deadly virus in Indonesia. It was confirmed that the 10-year-old child contracted the virus from his aunt and it spread to the father and other members of the family. The WHO is now conducting a large-scale investigation into the case of human-to-human transmission of bird flu.
The Health Ministry spokesman Samaye Mammadova told APA that no emergency sanitary regime is due to be held in Azerbaijan related to the investigation of new mutated form of the bird flu virus. She said precautions are being implemented.
The H5N1 virus has already killed more than 120 people worldwide since 2003. It has also devastated poultry stocks.
What's all the excitement about?
It isn't a mystery and it's not a conspiracy - but what exactly is the truth about Bird Flu? It has many Viewzone readers scared but is it really an impending catastrophe?
Once again, we'll try to deliver the facts in some down to earth language. And once again, YOU can decide if it's time to stockpile food and water or move the family to the countryside.
A flu virus that infects humans is called a "Human Influenza Virus." So the Bird Flu is actually both an Avian Flu Virus and a Human Influenza Virus. It is caused by a virus that typically "lives" in birds intestines, technically called the "H5N1 virus." I say "lives" with some hesitation because there is some doubt about whether or not a virus is a "living" thing.
A "living" organism is usually something like a plant or animal which takes in food, has a metabolism, excretes wastes and reproduces. A virus is different. It really has no internal organs and does not move or eat food. In fact, it only reproduces - and it doesn't even do that by itself. If you looked at a virus you would see that it is only a single or double strand of either DNA or RNA, -- a large molecule -- encapsulated in a shell of protein. The Bird Flu virus (H5N1) happens to be a single stranded-RNA type.
Influenza is another name for the flu, which you have probably had at some time in your life. Viruses that cause influenza in animals are called "Type A" viruses. There are many different subtypes of Type A viruses. These subtypes differ because of changes in certain proteins on the shell of the virus, specifically the proteins called hemagglutinin [HA] and neuraminidase [NA]. There are 16 known HA subtypes and 9 known NA subtypes of influenza A viruses. Many different combinations of HA and NA proteins are possible. Each combination represents a different subtype. All known subtypes of Type A viruses can be found in birds. Some only make the birds mildly sick and others can be fatal. The Bird Flu virus that concerns the world population today is called H5N1 because of the particular combination of hemagglutinin (HA type 5) and neuraminidase (NA type 1) that makes up the protein shell.
The shell is important because that is how a virus infects, or gets inside a cell, whether it is a chicken or duck cell or a human cell. Scientists call it the "lock and key" mechanism. Animal cell walls contain proteins that react when they are in contact with the virus shell proteins.Only certain protein molecules can react with other protein molecules and create openings, exposing the inner contents of the host cell wall to contaminants from the outside. This is how the single strand of RNA inside the H5N1 virus gets in to a bird cell. It's the reason that this virus can infect a bird and be essentially harmless to, say, a plant or a dog or an elephant.
Remember, the virus doesn't move. It doesn't "swim" of "fly" or "stalk" the host cell. In that sense it is not really "alive" -- and so it cannot technically be "killed." It merely comes in contact with it's host cell and the molecular structure of its protein shell does the rest. Once the cell wall has been "unlocked" and the virus RNA has entered the host, more chemical reactions automatically take place. The virus RNA molecule uses the cell contents to manufacture duplicate copies of itself along with more HA-5 and NA-1 protein molecules to encapsulate them. The process continues unfailingly until the cell contents are either depleted or until the cell literally explodes, distributing more copies of the virus to infect neighboring cells.
Pretty scary - right? But remember that viruses are part of our environment. We have all been infected by them, from chickenpox when we were a child to last year's flu or bad cold. Usually they are not lethal. So why is bird flu different?
50 percent mortality!
Bird Flu was first identified in Italy more than 100 years ago in poultry populations and is known to infect birds worldwide. Fifteen subtypes of influenza virus are known to infect birds, thus providing an extensive reservoir of influenza viruses potentially circulating in bird populations. To date, all outbreaks of the highly pathogenic form have been caused by influenza A viruses of subtypes HA-5 and HA-7.
Today, poultry are bred in large, dense populations that can spread the virus quickly to an entire population. We have also altered the chicken's genes, selecting them to mature quicker and to develop unusually large breasts. The so-called "broiler chickens" have been genetically altered so much that they would die before reaching natural maturity. But they are slaughtered and marketed before their grotesque anatomy proves fatal. These alterations to the natural design usually result in certain vulnerabilities to specific diseases and that may be the reason for the current ourbreaks of Avian Flu.
In 2003, outbreaks of H5N1 Bird Flu occurred among poultry in eight countries in Asia (Cambodia, China, Indonesia, Japan, Laos, South Korea, Thailand, and Vietnam). At that time, more than 100 million birds in the affected countries either died from the disease or were killed in order to try to control the outbreaks. The concern initially was that the disease could severely impact the economies of poultry farmers and impact the region's poultry food supply. Chickens are, in Asia, one of the main sources of meat.
By March 2004, the outbreak was reported to be under control.
Virtually all of the chickens in Vietnam and Thailand were killed within a two week period and many other countries followed suit.
Since late June 2004, however, new outbreaks of influenza H5N1 among poultry were reported in the same countries and in several other countries in Asia. Despite thorough attempts to eradicate the disease in poultry, these outbreaks are currently ongoing.
Recently, H5N1 infection also has been reported among poultry in Turkey, Romania, and Ukraine. Outbreaks of H5N1 have been reported among wild migratory birds in China, Croatia, Mongolia, and Romania. This latest trend suggests that the global spread of H5N1 seems unstoppable and inevitable.
H5N1 virus does not usually infect people, but more than 140 human cases have been reported by the World Health Organization since January 2004. Most of these cases have occurred as a result of people having direct or close contact with infected poultry or contaminated surfaces; however, a few cases of human-to-human spread of H5N1 have occurred, and that is the real concern of World health officials.
At first, only birds got sick from H5N1. Some were only mildly affected with ruffled feathers and lower egg production, but others soon died within a few days. This seems to show that the virus was mutating and changing into a more lethal form. Eventually poultry farmers and people who handled poultry got sick, probably from bird blood, feces or saliva. Humans infected with H5N1 became violently ill and about fifty-percent died!
You might think the prospect of never eating chicken again would save the world from this disease, but you would be dead wrong.
Darwinism and Destruction
Darwin's theory of evolution shows that organisms change over time to adapt to their environment and to survive. Survival is defined as living long enough to reproduce and continue the existence of the particular species.
An organism that kills its host in the process of reproducing itself gradually diminishes its own survival. Eventually there are no more hosts to infect and it becomes extinct. Thus, many scientists think that the H5N1 virus will eventually evolve into a less lethal entity. That's the good news. The bad news is that the virus will choose humans as its preferred host. They predict that the mortality among humans infected with the disease will drop from fifty percent to about fifteen percent or less.
The prime example of this is the great influenza pandemic of 1918 - 1919, which caused an estimated 40 to 50 million deaths worldwide, followed by pandemics in 1957 -1958 and 1968 - 1969.
The 1918 "Spanish" flu pandemic is estimated to have infected up to one billion people - half the world's population at the time.
The virus killed more people than any other single outbreak of disease, surpassing even the Black Death of the Middle Ages.
Although it probably originated in the Far East, it was dubbed "Spanish" flu because the press in Spain - not being involved in World War I - were the first to report extensively on its impact.
The virus caused three waves of disease. The second of these, between September and December 1918, resulting in the heaviest loss of life.
It is thought that the virus may have played a role in ending World War I as soldiers were too sick to fight, and by that stage more men on both sides died of flu than were killed by weapons.
Although most people who were infected with the virus recovered within a week following bed rest, some died within 24 hours of infection.
If you look at the 1918 flu, you see that the virus did not have a kill rate anywhere near 50 percent. It was more like 1.5 to 2 percent. But this virus was good at spreading from one host to another, which is what made it extremely dangerous. Consider the potential today with the improvements in air travel and tourism and the potential for global infection is enormous.
There is evidence that this mutation to a less lethal form has already begun with H5N1. Dr. Tim Uyeki, a medical epidemiologist at the Centers for Disease Control and Prevention, reported that,
"Among market poultry workers," he says, "about 10 percent had antibodies to H5N1 virus, suggesting that they had been infected. But these were people who never were identified as severe cases, had never been hospitalized."
Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, says public health officials are preparing for the worst. But in this case, that means a mortality rate closer to 2 percent than 50 percent.
But Dr. Frederick Hayden of the University of Virginia urges caution.
"This virus so far has not shown any diminution in virulence for birds or for mammalian hosts," Hayden says. "If anything, we're seeing evidence of increased pathogenicity."
No human-to-human transmission... yet.
Earlier this year, World Health Organization officials thought a human-contagious outbreak actually was happening in Thai Binh province, a couple of hours southeast of Hanoi. It started with a 21-year-old man named Nguyen Sy Tuan. He helped his parents slaughter chickens. Then he fell ill. His 14-year-old sister became sick, too.
Tuan's mother and aunt took him to the Thai Thuy District Hospital. A nurse named Nguyen Duc Thinh helped him to his bed and took care of him through the night.
"First, because we didn't have an X-ray, I was just thinking it was fever, high fever. We were thinking of pneumonia," he says.
It wasn't pneumonia. It was bird flu. Then a few days later, something alarming happened. Nurse Tinh fell ill himself, with high fever and difficulty breathing.
"I thought I might die," he said. "I was in crisis. I am frightened at that time. Spiritually, yes, I'm afraid."
Experts feared that the crisis had begun -- that the virus had learned to spread from person to person.
But no more cases occurred in Thai Thuy. Investigators say the nurse might have been exposed to sick poultry. But the possibility of human-to-human transmission galvanized officials here. Now they know they have to watch for signs of flu not just in birds but in people.
Several cases in Turkey in January 2006 have had officials fearing that the virus has mutated to a human-to-human form, but the evidence is not yet conclusive. And so the global health community waits in fear to learn if the deadly mutation has happened yet. It's not really a case of "if" -- but "when."
What about a vaccine?
You might think that, in this 21st Century, we could develop a vaccine to protect humans against the H5N1 virus. It certainly seems feasible, but there are a few major problem unique to this virus.
Harold Slevin, from Solvay Pharmaceuticals, says his company's current reliance on millions of chicken eggs for vaccine manufacture makes him nervous.
At that point, a pandemic could already have spread around the world. Even then, there wouldn't be enough vaccine to go around, unless there's a new way to make vaccines -- and the capacity to make billions of doses in a hurry.
Solvay Pharmaceuticals has developed a new way to produce flu vaccines. This relies on a line of immortal cells, harvested from a cocker spaniel's kidney way back in 1958 and kept alive ever since. This approach is called cell-based technology.
Harold Slevin explains the process:
Gary Nabel, who runs one of the nation's premier vaccine labs at the National Institutes of Health, in Bethesda, Md., says,
What about the cell-based vaccines? They're not even being manufactured in any kind of large scale. Why? It's an economic issue. The pharmaceutical companies that manufacture these vaccines don't want to get burned by holding a bunch of inventory for a vaccine nobody needs. Of course, there's a chance the bird flu virus might be a big dud. If you're a vaccine manufacturer, you don't want to manufacture 100 million dollars worth of product just on the off-chance that some nation might need it and buy it from you.
There is an anti-viral pharmaceutical drug, Tamiflu, that has shown some effectiveness in treating H5N1 after it is contracted, but there is no guarantee that the evolving virus will be affected by this medication. Many of these anti-viral drugs are also expensive and supplies are limited. The US has only enough supplies of Tamiflu to treat healthcare workers and other "essential" personnel, but discussions about stockpiles of a larger supply have been on-going. Even with these efforts there is little guarantee that a mutation of H5N1 would respond to treatment by Tamiflu and so the inevitability of the global pandemic seems unstoppable.
Breakthrough in Bird Flu Vaccine
Washington - A new bird flu vaccine made using cleaner technology took just a month to make and completely protected chickens from the deadly H5N1 virus, US researchers reported on Thursday.
The team at the University of Pittsburgh is now putting together a plan to test the vaccine in humans.
"This is a very potent vaccine," Dr. Andrea Gambotto of the University of Pittsburgh School of Medicine, who led the study, said in a phone interview.
"It took roughly about 30 days to make the vaccine from when we received the sequence information from CDC in Atlanta."
Current influenza vaccines for both chickens and humans take months to make and are grown in chicken eggs. Production is uncertain and the vaccines do not provide perfect protection.
Experts agree the way to go is cell-based production - growing the vaccine in batches of human cells grown in the lab instead of in eggs.
Several shortages of vaccine for the seasonal flu made this need even more dire. But the spread of the H5N1 virus has made the need for better vaccine technology urgent.
H5N1 affects mostly birds but it has infected more than 150 people and killed more than 80 of them. Experts fear it could acquire the ability to pass from person to person, sparking a pandemic that could kill millions around the globe.
Because no one knows just how H5N1 will mutate, experts say it will not be possible to start making a vaccine against it until the pandemic strain emerges.
Gambotto hopes his team's approach will provide a way to start making such a vaccine quickly.
From Email to a Vaccine
They did not use the actual H5N1 virus - just genetic sequence data from the Centers for Disease Control and Prevention. "We have the technique to go from an e-mail to a virus," Gambotto said.
They artificially generated the DNA coding for the hemagglutinin gene - which controls a protein found on the surface of all influenza viruses and provides the "H" in a virus's name.
"We generated the portion that we think was important for immunity," Gambotto said. "We never manipulated the actual H5N1 virus ourselves, so it is safe to generate this kind of vaccine."
They then spliced this artificial DNA into a human adenovirus, a common cold virus.
Tests in mice and chickens showed it provided partial protection when given nasally, and 100 percent protection against H5N1 when injected, they report in the February 15 issue of the Journal of Virology.
And it produced what is known as a dual immunological response - the body generated both antibodies to neutralize the virus, and T-cells, a kind of immune cell that also attacks viruses.
"That means there is a lot of chance of getting cross-reactivity," Gambotto said. In other words, the vaccine may work against mutated versions of the flu virus, something current vaccines cannot do. This is why the flu vaccine now must be reformulated every year.
Gambotto also hopes the nasal vaccine might work better in people than it did in animals, because the vaccine uses a live human adenovirus.
His team is working with the US Food and Drug Administration to get approval to move ahead with human trials.
The university has the technology to make and test its own vaccines. "Eventually we will need to partner with a company for large-scale production of vaccine," Gambotto said.
Blame 'Big Chicken'
By Wendy Orent
Chicken never has been cheaper. A whole one can be bought for little more than the price of a cup of coffee from Starbucks. But the industrial farming methods that make ever-cheaper chicken possible also may have created the lethal strain of bird flu virus, H5N1, that threatens to set off a global pandemic.
According to University of Ottawa flu virologist Earl Brown, lethal bird flu is entirely man-made, first evolving in commercially produced poultry in Italy in 1878. The highly pathogenic H5N1 is descended from a strain that first appeared in Scotland in 1959.
People have been living with backyard flocks of poultry since the dawn of civilization. But it wasn't until poultry production became modernized and birds were raised in much larger numbers and concentrations that a virulent bird flu evolved. Somehow, the virus that arose in Scotland found its way to China, where, as H5N1, it has been raging for more than a decade.
Industrial poultry-raising moved from the West to Asia in the last few decades and has begun to supplant backyard flocks there.
Poultry may represent a family's greatest wealth. The birds often are not eaten until they die of old age or illness. The cost of the virus to people who have raised birds for months or years is incalculable and the compensation risible: In Thailand, farmers have been offered one-third of their birds' value since the outbreak of bird flu.
Some researchers still blame migratory birds for the relentless spread of the bird flu virus. But Martin Williams, a conservationist and bird expert in Hong Kong, contends that wild birds are more often victims than carriers.
Researchers concede that the global poultry trade, much of which is illicit, plays a far larger role in spreading the virus.
The Nigerian government traced its outbreak to the illegal importation of day-old chicks. Illegal trading in fighting cocks brought the virus from Thailand to Malaysia in fall 2005. And it is probable that H5N1 first spread from Qinghai to Russia and Kazakhstan last summer through the sale of contaminated poultry.
But an increasingly hysterical world targets migratory birds.
In early February, a flock of geese, too cold and tired to fly, rested on the frozen waters of the Danube Delta in Romania. A group of 15 men set upon them, tossed some into the air, tore off others' heads and used still-living birds as soccer balls. They said they did this because they feared the bird flu would enter their village through the geese. Many conservationists worry that what happened in Romania is a foreshadowing of the mass destruction of wild birds.
Meanwhile, deadly H5N1 is washing up on the shores of Europe.
Brown, the virologist, says the commercial poultry industry, which caused the catastrophe in the first place, stands to benefit most. The conglomerates will more and more dominate the poultry-rearing business. Some experts insist that will be better for us.
For instance, epidemiologist Michael Osterholm at the University of Minnesota contends that the "single greatest risk to the amplification of the H5N1 virus, should it arrive in the U.S. through migratory birds, will be in free-range birds ... often sold as a healthier food, which is a great ruse on the American public."
The truly great ruse is that industrial poultry farms are the best way to produce chickens -- that they are keeping the world safe from backyard poultry and migratory birds. But what's going to be on our tables isn't the biggest problem.
The real tragedy is what's happened in Asia to people who can't afford cheap, industrial chicken. And the real victims of industrially produced, lethal H5N1 have been wild birds, an ancient way of life and the poor of the Earth, for whom a backyard flock has always represented a measure of autonomy and a bulwark against starvation.
Wendy Orent is the author of "Plague: The Mysterious Past and Terrifying Future of the World's Most Dangerous Disease."
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"Bird Flu", also called "Avian (Latin for "bird") Flu Virus" is a disease that has been known to infects birds and currently has infected some humans. 
One of the problems facing the Asian countries is the tradition of keeping chickens and ducks in free range farms surrounding small villages and residential areas. Another problem is that countries, like Cambodia, have minimal authority to enforce culling of poultry in remote villages. Police and health workers are usually concentrated in urban areas, where the poultry is sold, but have insignificant influence over family farms where chickens and ducks mingle freely with pigs and dogs and humans.
The H5N1 virus isn't a perfect creation. When it uses the internal contents of a host cell to make duplicates of it's RNA and protein it often makes mistakes -- it's sloppy. Sometimes it uses parts of the hosts RNA or DNA. Other times it will invade a cell that has already been infected with a different virus and incorporates some of that material in is reproductions. In the past, this mixing of genetic material has taken place inside pigs, which usually live alongside ducks, geese and chickens in rural areas. The incorporation of pig genetics in copies of the virus is extremely dangerous since the pig genes closely resembles human genetic material. Many diseases that infect piugs can also infect humans. These subtle changes and mutations can make the virus unpredictable and deadly.
First, most vaccines are manufactured using - yes - chicken eggs! This 50-year old technology is not very nimble. With governments and global health organizations taking the threat of a flu pandemic seriously, a big push is on to develop new and faster ways to make flu vaccines.
The genetically engineered vaccine appears to fulfill the promise of modern influenza vaccine technology being pushed by public health experts who want to improve the slow, old-fashioned methods now used to fight the flu.