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By RANDOLPH E. SCHMID
WASHINGTON (AP) -- The federal government is getting ready to test a bird flu vaccine and stockpiling both vaccine and antiviral drugs as the threat grows that a deadly strain of avian influenza will begin spreading from Asia.
Two million doses of vaccine are being stored in bulk form for possible emergency use and to test whether it maintains its potency, officials said Wednesday.
United Nations officials warned that the Asian bird flu outbreak poses the "gravest possible danger" of becoming a global pandemic.
Dr. Julie Gerberding, director of the federal Centers for Disease Control and Prevention, told the National Press Club this week that "it is a worrisome situation," though she also said the United States "is not immediately on the brink of an avian flu epidemic."
The flu has affected poultry in eight Asian countries, with 45 human deaths among people who caught the illness, a strain of flu known as H5N1.
So far, humans appear to have caught this flu from chickens and other poultry, and the virus is not known to have spread from person to person.
What health authorities most fear is that the virus will mutate into a form that can pass easily from one human to another. That's when a global threat would be most likely.
The deadly flu of 1918, which killed from 20 million to 50 million people worldwide, didn't appear suddenly but mutated gradually into the deadlier form, Gerberding explained.
"That's why it's important to have flu vaccine and antivirals, to be ready to react when it starts to emerge," she said.
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World health officials meeting in Vietnam say current conditions could lead to a global epidemic and ask the West to provide aid.
By Charles Piller and Thomas H. Maugh II, Times Staff Writers
HO CHI MINH CITY, Vietnam — As Vietnam reported 27 new outbreaks of bird flu, public health officials meeting here called for a massive transformation in poultry farming throughout Southeast Asia to stem the epidemic.
The biggest challenge will be to reform the practices of millions of subsistence farmers who share living space with their chickens, ducks and other animals.
Scientists said such conditions created a hothouse for mutations in the flu virus that eventually could enable it to pass easily between people, a precondition for a possible pandemic.
American officials, meanwhile, said they were nearing the start of a large clinical trial of an experimental avian flu vaccine that could help suppress the virus if it spread beyond Southeast Asia.
The "backyard farmers" of Vietnam, which has borne the brunt of the latest outbreak, raise about 90% of the country's poultry, Cao Duc Phat, the nation's agriculture minister, said at a news conference during a three-day meeting convened by the World Health Organization.
Among other recommendations, officials urged that chickens and other fowl be kept out of homes, that different species of birds be segregated on farms and in markets to limit spread of the virus, and that domestic fowl be kept penned up to prevent them from mingling with the wild ducks that are thought to be a natural reservoir for the virus, formally known as H5N1.
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Editorial Note: This widespread AP story was probably the first time 98 per cent of the US population heard of this development.
WASHINGTON (AP) -- A bird flu virus may mutate to a human form that becomes as deadly as the ones that killed millions during three influenza pandemics of the 20th century.
Dr. Julie L. Gerberding, head of the Centers for Disease Control and Prevention, said Monday that scientists believe it is highly likely that the virus that has swept through bird populations in Asia will evolve into a pathogen deadly for humans.
"We are expecting more human cases over the next few weeks because this is high season for avian influenza in that part of the world," Gerberding said in remarks at the national meeting of the American Association for the Advancement of Science.
Although cases of human-to-human transmission have been rare, "our assessment is that this is a very high threat" based on the known history of the flu virus, she said.
In Asia, there have already been a number of deaths among people who caught the flu from chickens or ducks. The mortality rate is very high -- about 72 percent of identified patients, said Gerberding. There also have been documented cases of this strain of flu being transferred from person-to-person, but the outbreak was not sustained, she said.
The avian flu now spreading in Asia is part of what is called the H1 family of flu viruses. It is a pathogen that is notorious in human history.
"Each time we see a new H1 antigen emerge, we experience a pandemic of influenza," said Gerberding. In 1918, H1 appeared and millions died worldwide. In 1957, the Asian flu was an H2, and the Hong Kong flu in 1968 was a H3.
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Helen Pearson
Bolstering support for the field remains a thorny problem.
An analysis of studies in 40 countries around the globe proves a long-standing assumption: that the more a person knows about science, the more he or she tends to support scientific endeavours.
The issue is a fundamental one for scientists and science teachers. They often assume that improving people's scientific literacy will boost support for research, encourage young people to choose science careers and clear up damaging misconceptions about miracle cures or pseudoscience.
In fact, studies that have tested the link between a person's level of scientific knowledge and attitudes towards the field have generated mixed results. "It's been a very vexed question," says sociologist Nick Allum of the University of Surrey in Guildford, UK.
To try and resolve the issue, Allum and his colleagues pulled together the results of nearly 200 surveys carried out between 1998 and 2003 in countries from Australia to Bulgaria. These studies assessed, for example, whether participants knew certain scientific facts and whether they supported developments in genetically modified food or nanotechnology.
Causal concerns
To some extent, the results confirm the belief widely held by science advocates: the more people know about science, the more favourably they tend to view it, regardless of other factors such as age, nationality and formal level of education. Allum presented his results at the meeting of the American Association for the Advancement of Science in Washington DC last week.
But now this question is cleared up, researchers must begin to tackle more pressing questions, Allum says. "The argument should move on."
His finding cannot, for example, show whether better science education will bump up general support for the field. This is because researchers have yet to figure out whether people who learn more about science then tend to like it or, conversely, whether people who already like and support science are simply inclined to learn further facts.
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By ANDREW POLLACK
IRVINE, Calif. - Hans S. Keirstead might be the Pied Piper of stem cells - and not just because he makes rats walk. He also helped lure Californians to the polls last fall to approve spending $3 billion of the state's money on embryonic stem cell research over the next decade. But he has critics who worry that he may be leading their new field too far, too soon into uncharted territory.
Dr. Keirstead, an assistant professor at the University of California campus here, has been making paralyzed rats walk again, using a treatment based on human embryonic stem cells. Next year he and his corporate partner, Geron, plan to try treating people who have recent spinal cord injuries, in what would almost certainly be the first human trial of any therapy derived from such cells.
"You've got a patient community out there that is in desperate need," Dr. Keirstead said in an interview. "If the treatment is safe, let's get it out there and try it."
And to those who argue that it is too soon to test his technique on humans, he has an answer. "There will always be people who say slow down, slow down," he said. "I guarantee you none of them have relatives in wheelchairs."
With his gung-ho attitude, the good looks of a surfer and a compelling story to tell, Dr. Keirstead, 37, emerged as one of the leading scientific voices behind the movement that persuaded California voters last November to approve a measure to sidestep federal funding restrictions on stem cell research. His supporters included people with spinal cord injuries, most notably Christopher Reeve, the wheelchair-bound actor who taped a campaign ad citing Dr. Keirstead's research just before he died in October.
But for all of Dr. Keirstead's fans and backers, a number of researchers in California and elsewhere say the scientific validity of his work has not been proved and the technique might not be ready for testing in people. A failure in the first high-profile human test could dash some of the hope spawned by the passage of the California ballot measure.
"A lot of things make rats better," said Jerry Silver, a neuroscientist at Case Western Reserve University, who argued that Dr. Keirstead should test his treatment in dogs or monkeys first. "You can't announce you are going into humans because you've gotten good results in rats."
Mark H. Tuszynski, a professor and director of the center for neural repair at the University of California, San Diego, echoed that view. "I think the jury is still out," he said, "on whether this is a useful approach." Dr. Tuszynski, co-founder of a company trying to use gene therapy to treat neurological diseases, said he would prefer to see "more compelling evidence" from Dr. Keirstead's work before human testing.
The new California stem cell research board that was set up after passage of last fall's ballot measure, Proposition 71, is still organizing itself and figuring out how to begin awarding public grants to scientists. But Dr. Keirstead has been able to speed forward, fueled by money from Geron, a California biotechnology company, which is eager to demonstrate to investors that practical use of stem cells is not a distant dream.
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Constance Holden
Researchers in Wisconsin have cleared a critical hurdle on the path to treating disease with human embryonic stem (HES) cells. Their newly developed cell culture method eliminates the need for mouse-related components. Scientists call the work a big step toward abolishing contamination and ensuring that the cells will not be rejected when transplanted into a human patient.
The recipe for maintaining HES cells in the lab usually calls for non-human ingredients, including mouse feeder cells or mouse-conditioned growth medium. These components help keep the cells undifferentiated and able to be transformed into almost any bodily tissue. In the past few years, several groups have announced success in growing stem cells in media free of mouse factors. But none of them has sustained the cells over time, says developmental biologist Ren-He Xu of the WiCell Research Institute in Madison, Wisconsin. A group in Singapore has claimed success using human feeder cells, but Xu says human cells comprise an "unknown mixture" of compounds, some of which could be pathogenic.
Xu's team, which includes James Thomson (who first successfully derived HES cells), has now gotten rid of what is regarded as the primary contaminant: the mouse-conditioned medium. The team found that high doses of a synthetic human molecule known as fibroblast growth factor 2 (FGF2) can itself sustain stem cells in an undifferentiated state. FGF2 works by inhibiting the activity of bone morphogenetic protein (BMP), a molecule that promotes stem cell differentiation. That means researchers no longer have to rely on mouse components for this function, says Xu, whose team reports its findings in the March issue of Nature Methods.
The study is "a major step forward," says Ajit Varki, professor of medicine at the University of California, San Diego. He warns, however, that much work lies ahead. His group found that a serum component of the cell medium, which is derived from cows, was "the major source of contamination" for HES cells.
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SEOUL, South Korea It's 10.30 on Friday night, and scientists and doctors prepare to enter a veterinary hospital operating room at Seoul National University.
CNN has been invited by one of South Korea's leading cloning experts, Dr. Hwang Woo-Suk, to witness a rare event in genetic science, the birth of "humanized" pigs.
These genetically modified animals' organs have been tailor-made so that the size of them will allow them to be transplanted into humans.
Pig heart valves are widely used to patch up human hearts but one of the biggest problems in using the entire organ is ensuring the human body doesn't reject it.
The process to deliver the tailor-made piglets takes less than five minutes.
As the impregnated pig is sedated, her entire uterus is removed and placed in a sanitary incubator so that the baby pigs will be germ-free as soon as they are born.
The clean environment is important in order to prevent pig diseases being transferred to human organs.
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