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    Avian Bird Flu

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    Awaiting Lengthy Lab Confirmation of Bird Flu Risks Treatment Delays, Studies Find

    Monday 27th of November 2006 09:49:00 PM

    November 26, 2006

    Awaiting Lengthy Lab Confirmation of Bird Flu Risks Treatment Delays, Studies Find

    By DONALD G. McNEIL Jr.



    Because detecting Avian flu with standard tests is so difficult and time-consuming, waiting for laboratory confirmation of an outbreak would cause dangerous treatment delays, according to new studies of two flu outbreaks.



    The studies, published Thursday in The New England Journal of Medicine, were of family clusters of flu cases in Turkey and Indonesia.



    Rapid tests on nose and throat swabs failed every time, and in Turkey, so did all follow-up tests known as Elisas. The only tests that consistently worked were polymerase chain reaction tests, or PCRs, which can be done only in advanced laboratories and take several hours.



    ?It?ll be a disaster if we have to use PCRs for everybody,? said Dr. Anne Moscona, a professor of pediatrics and immunology at Weill Cornell Medical College. ?It just isn?t available at a whole lot of places.?



    If the A(H5N1) flu mutates into a pandemic strain, rapid tests ?will be really key,? she said.



    The studies followed clusters in three families in Indonesia in 2005 and in what appears to have been one extended family near Dogubayazit, in eastern Turkey, in January. Case clusters particularly worry public health authorities because they raise the possibility that the flu is mutating to spread faster between people.



    In the Indonesian cases, the authors, from Indonesia, the World Health Organization and the Centers for Disease Control and Prevention in Atlanta, concluded that human-to-human transmission had probably taken place in two of the three family clusters. In one case, a 38-year-old government auditor appeared to have caught the flu from his 8-year-old daughter or her 1-year-old sister. All three died; his wife and two sons did not get sick. No one in the family had any known contact with poultry, wild birds, animals or sick people, so the source was a mystery.



    ?But you can?t always tell what a young child has done,? said Dr. Tim Uyeki, a Centers for Disease Control flu specialist and an author of the study. ?There?s no magical test, and you don?t always get a perfect explanation.?



    The Dogubayazit cluster was a cause célèbre for some Internet flu-watchers following Turkish news reports in January. They contended that widespread human-to-human transmission seemed to be taking place, and that it may have begun at a banquet attended in late December by members of two related families named Ozcan and Kocyigit. The Turkish government and the World Health Organization did not link the cases or families and tentatively blamed birds for all transmission.



    The studies showed how wide a net was cast: 290 people were tested at one hospital because they either had flu symptoms or contact with dying birds, or both. All were given the antiviral drug oseltamivir, which is also sold as Tamiflu, and about half were hospitalized. That accorded with health organization recommendations: widespread testing and use of antivirals, both to save lives and to snuff out any suspected outbreak of a mutant strain.



    Only 10 came up positive on PCR tests, and 8 of those were confirmed by a World Health Organization laboratory. All were children; four died. The studies confirmed suspicions that the families were linked; 7 of the 8 children were related or lived near each other. The December banquet was not mentioned.



    It was impossible to tell whether the other argument made by the Internet flu-watchers was correct: that poor testing and the oseltamivir had disguised the extent of the outbreak. But the lead author, Dr. Ahmet Faik Oner, a professor of medicine at Yuzuncu Yil University in Turkey, said in a telephone interview that he believed that there had been no human-to-human transmission because all the children had been in close contact with poultry within seven or fewer days before they fell ill and none of their parents or the hospital staff members that treated them had become sick.



    Dr. Uyeki declined to comment on the Turkey outbreak, but said both studies lent support to the theory that some people were genetically more susceptible to the flu.


    From Research This Blog Entry

    Junk medicine: pandemic flu

    Monday 27th of November 2006 09:40:00 PM

    The Times

    November 25, 2006

    Body&Soul

    Junk medicine: pandemic flu
    Mark Henderson
    Take risks to save lives

    The H5N1 bird flu virus is changing. It emerged last week that it has acquired two mutations that suit it better to infecting human cells. It has not triggered a pandemic yet, and may never do, but these are the sort of developments we would see if the worst- case scenario were unfolding.

    Britain is among the countries that are best prepared for this. The Government?s contingency plans have won international praise, and the decision to stockpile 14.6 million doses of the antiviral agent Tamiflu means that a first line of defence is in place.

    The lack of room for complacency, though, was highlighted by this week?s report from the Royal Society and the Academy of Medical Sciences. It found that while the Tamiflu order is a necessary measure, it is not sufficient. There is a good case for buying a lot more, so it can be used preventively. And supplies of a second antiviral, Relenza, are also needed, as there are signs that H5N1 could become resistant to Tamiflu. An alternative weapon is essential.

    Another way of protecting against a pandemic, of course, is vaccination. But as the report cautioned, this is fraught with difficulty. Production capacity is limited by demand for seasonal flu jabs, currently about 350 million a year. It would be difficult to cover more than a small fraction of the world?s 6.5 billion people.

    On top of that, an effective vaccine can be designed only once the precise pandemic strain is known. Safety testing, regulatory approval and manufacturing mean a delay of seven to nine months before anyone can be immunised. Millions would be dead before the first injection is given.

    The first problem will probably be impossible to solve. It is impractical for industry or governments to build vaccine factories and mothball them. The priority should be research into adjuvants, additives that get more response from vaccines at lower doses.

    The second issue also looks intractable. But as Professor Nick White, a flu specialist at the Wellcome Trust, pointed out in the Natural History Museum?s annual science lecture, that is true only up to a point. Some manufacturing delays are inevitable, but weeks or even months might be saved by cutting corners on research.

    Under normal circumstances, it is right and proper that vaccines are assessed rigorously and produced to the highest standards to prevent side effects. A pandemic, though, is not a normal circumstance. Professor White argued persuasively that trading off a little more risk for speed might be a bargain worth making. ?Have we become too risk-averse to move quickly?? he asked. ?We need to think as a society about underwriting scientists to run risks.? A saving of a month would not allow a vaccine to be used in the first phase of a pandemic, but it might make all the difference against its second wave. The vaccine might itself cause deaths, but this must be set against lives saved by speed. The balance of risks and benefits is not yet clear, but this is certainly a debate worth having.

    It is not one that has much engaged the Government so far. As Professor White said, it would get fuller consideration if ministers were to accept another of the Royal Society?s recommendations: the appointment of an expert scientist as ?flu czar?.

    The Chief Medical Officer and the Chief Scientific Adviser have done fine work on pandemic preparedness, but both have significant other responsibilities. They cannot be expected either to be influenza specialists or to give the issue the time it warrants. The UK is fortunate in that many of the world?s leading authorities on pandemic flu are based here: Professor Neil Ferguson of Imperial College London and Sir John Skehel of the National Institute for Medical Research are two of them.

    It is critical that their voices are heard at the highest level. Mark Henderson is Science Editor of The Times

    Copyright 2006 Times Newspapers Ltd.


    From Research This Blog Entry

    Three years into H5N1 outbreak, new research highlights how little is known

    Thursday 23rd of November 2006 11:11:00 PM

    Three years into H5N1 outbreak, new research highlights how little is known

    Published: Wednesday, November 22, 2006 | 8:14 PM ET

    Canadian Press: HELEN BRANSWELL



    (CP) - Three years into the outbreak of the H5N1 avian flu virus, two international teams of researchers scored major scientific credibility points Wednesday when the New England Journal of Medicine published their articles on the diagnosis and treatment of a mere 16 H5N1 patients.



    With the official World Health Organization case count hovering near 260 human cases and 153 deaths from 10 countries, it might seem that the problems Turkish doctors experienced diagnosing eight patients in January or the investigation of three clusters of Indonesian patients last year wouldn't rate publication in the world's most prestigious medical journal.



    But in fact, there is so little clinical and epidemiological information about H5N1 disease in the scientific literature that experts are eagerly welcoming the addition.



    "Boy, it would just be nice to have more of this information out there," Dr. Keiji Fukuda, who heads the WHO's global influenza program, said in an interview from Geneva.



    "It's tough. It's not easy getting this information."



    A deputy editor of the journal agreed the information charting the virus in people is sparse.



    "The number of documented human cases of H5N1 and the number of deaths attributed to it - well-characterized - is still a relatively small number," Dr. Lindsey Baden explained.



    "We as a scientific and public health community need to have well-characterized the known human cases so that appropriate lessons can be learned."



    Potential lessons from these papers include the observation by the Turkish researchers - from Yuzuncu Yil University in Van - that laboratories inexperienced with testing for H5N1 may have trouble confirming infections. They urged doctors in areas where there are H5N1 outbreaks in poultry to repeat sample taking and testing if initial tests come up negative for patients manifesting an H5N1-like disease.



    The Indonesian paper points to the need to follow up with contacts of H5N1 patients. Three of the eight patients reported in the article experienced only mild disease and only came to light when investigators looked for illness in hospitalized cases.



    The article noted limited human-to-human transmission may have occurred in two of the three clusters.



    Both papers noted that diarrhea was rare among their H5N1 patients - a departure from the case description already in the medical literature. That may be due to the fact that the Turkish and Indonesian cases were caused by a different subgroup of viruses (called a clade) than cases outlined in earlier reports. But one of the authors of the Indonesia paper cautioned against drawing too many conclusions on too few patients.



    "It would be interesting to look at clade 2 (infections) versus clade 1 (cases)," said Dr. Tim Uyeki of the U.S. Centers for Disease Control.



    "But right now, it's not quite fair to do that. . . . There's a need for more epidemiological and clinical data on H5N1 patients."



    The WHO is hoping to fill those knowledge gaps more efficiently in the future.



    Scientists working with Fukuda are devising a checklist of basic information they hope attending doctors will collect for each future case of H5N1 infection - recording when people got sick, what symptoms they experienced, what their blood testing showed, which drugs they received and when, how patients responded, and which survived.



    "Because there's no place that's having - fortunately - large numbers of cases, the only way to try to do this in a meaningful way is to collect as many of the cases from the different countries as possible," Dr. Frederick Hayden, a WHO scientist involved in the project, explained in a recent interview.



    Collecting and sharing standardized information is the only way to start teasing out answers to the myriad questions that continue to puzzle scientists. With so many people exposed to this virus, why do so few get sick? Why do so many clusters of cases among blood relatives occur? Why do children make up such a disproportionate number of the total cases?



    When considering the slow accumulation of H5N1 data, it's tempting to contrast it against the world's most recent emerging infectious disease experience - SARS.



    But Dr. Malik Peiris - a leading SARS and influenza expert from the University of Hong Kong and an author of the Indonesian paper - cautioned that the analogy isn't a good one.



    SARS exploded, triggering major outbreaks in places like Hong Kong, Taiwan, Hanoi and Toronto. The large volume of cases in teaching hospitals steeped in a tradition of research led to the rapid unravelling of an impressive number of SARS mysteries.



    By comparison, H5N1 cases have occurred in random fashion in remote locales - villages in Cambodia, Indonesia, Vietnam, Azerbaijan, even war-torn Iraq.



    "Here the cases are so dispersed," Peiris said. "There are so many clinicians involved, so many people involved, I think it makes it very difficult to pull these cases together from many different hospitals into one single analysis."



    An infectious diseases expert not involved with the papers noted that it's not surprising so many questions remain about H5N1, given the enormous number of mysteries that remain unanswered about seasonal influenza.



    "There are many, many questions with regard to influenza that have really only been recognized as important issues over the past 36 months," said Dr. Michael Osterholm, director of the University of Minnesota's Center for Infectious Diseases Research and Policy.



    "We want to basically have this breadth of information (about H5N1) that's far and wide, and how do you do it when you're dealing with a disease that's only had 250-some cases documented from beginning to end right now?"



    Even with a standardized form for data collection, accumulating information about the disease will remain challenging if cases continue to occur here and there in remote parts of the globe.



    "Those very painstakingly developed studies and systems require people to come in - and that's a complete haphazard thing," Fukuda said.



    © The Canadian Press, 2006


    From Research This Blog Entry

    Severe Flu Pandemic May Cost U.S. $623 Billion, World Bank Says

    Thursday 23rd of November 2006 11:06:00 PM

    Severe Flu Pandemic May Cost U.S. $623 Billion, World Bank Says



    By Jason Gale



    Nov. 23 (Bloomberg) -- A severe influenza pandemic would cost the U.S. $623 billion, or about 60 times more than an average flu season, and ``constitute a major global recession,'' the World Bank said.



    Economists at the Washington-based World Bank estimated a contagion capable of killing more than 1 percent of people worldwide could cause losses of $1.5 trillion to $1.8 trillion globally. The spread of the H5N1 avian influenza strain has put the world closer to another pandemic than at any time since 1968, when the last of the previous century's three major outbreaks occurred, according to the World Health Organization.



    The Bank, which funds projects to alleviate poverty, is working with countries to improve hospitals and laboratories to bolster disease surveillance and management of avian flu. Human fatalities from the H5N1 strain of the virus this year have surpassed the previous two years combined, providing more chances for the virus to mutate into a lethal pandemic form.



    ``Even with such efforts, an eventual human pandemic at some unknown point in the future is virtually inevitable,'' the Bank said in an e-mailed report today. ``Because such a pandemic would spread very quickly, substantial efforts need to be put into place to develop effective strategies and contingency plans that could be enacted at short notice.''



    The H5N1 virus is known to have infected 258 people in 10 countries in the past three years, killing 153 of them, the WHO said on Nov. 13. Millions could die if H5N1 becomes as easily transmissible between people as season flu.



    Seasonal flu causes the deaths of as many as 500,000 people annually. In the U.S., the disease results in about 36,000 deaths and more than 200,000 hospitalizations each year, costing more than $10 billion, the White House said in a statement last year.



    Egyptian Patient



    Egypt reported a suspected new human case in the central city of Sohag, the Al-Ghomhuria newspaper reported today, without saying where it got the information. A 25-year-old woman was transferred to the hospital for treatment, the newspaper said.



    A pandemic can start when a novel influenza A-type virus, to which almost no one has natural immunity, emerges and begins spreading. Experts believe that a pandemic in 1918, which may have killed as many as 50 million people, began when an avian flu virus jumped to people from birds.



    Disease trackers are monitoring for signs the virus is becoming adept at infecting humans, not just birds. The H5N1 strain was first detected in a farmed goose a decade ago in Guangdong, the same province of China where severe acute respiratory syndrome, or SARS, was reported in 2003.



    SARS Experience



    During SARS, air travel to Hong Kong plunged by as much as 75 percent during the worst four months of the epidemic and retail sales fell by an average of 9 percent, the World Bank said in its report, ``Evaluating the Economic Consequences of Avian Influenza,'' by Andrew Burns, Dominique van der Mensbrugghe and Hans Timmer.



    The World Bank's economic modeling for a flu pandemic assumed a 20 percent decline on an annualized basis in air travel and other mass transportation, as well as in services such as restaurant dining, tourism and non-essential retail shopping. Pandemics are typically experienced in at least two waves, with infections peaking in winter, the authors said.



    That could cause the world economy to shrink by 3.1 percent, while gross domestic product could be cut by as much as 4.4 percent in Latin America and the Caribbean, the study said.



    ``Developing countries would be hardest hit because higher population densities and poverty accentuate the economic impacts in some countries,'' the authors said.



    The world economy may contract by 4.8 percent during the first year of a ``severe'' pandemic, 2 percent in a ``moderate'' outbreak and less than 1 percent in the event of a ``mild'' pandemic.



    `Purely Illustrative'



    ``Given the tremendous uncertainties surrounding the possibility and eventual nature of a pandemic inflation, these simulations must be viewed as purely illustrative,'' the World Bank said. ``They provide a sense of the overall magnitude of potential costs. Actual costs, both in terms of human lives and economic losses, are likely to be very different.''



    Poultry farmers in infected countries have already suffered because of outbreaks. The World Bank in January estimated the cost at $10 billion in Asia alone. The virus has since been found in wild birds and domestic poultry in at least 38 countries in Asia, Africa, the Middle East and Europe.



    South Korean health inspectors are testing poultry for H5N1 on a farm where 6,000 birds died this week in the southwest of the Korean peninsula, the agricultural ministry said in a briefing today.



    In Somalia, dozens of bird carcasses have been found in Elbaraf, 55 kilometers (34 miles) north of the town of Johwar, raising fears of an H5N1 outbreak in the Horn of Africa, Reuters reported today, citing Ali Hamud, a local veterinarian.



    To contact the reporter on this story: Jason Gale in Singapore at j.gale@bloomberg.net

    Last Updated: November 23, 2006 08:14 EST


    From Research This Blog Entry

    Outbreaks Show Bird Flu Virus Is Changing

    Wednesday 22nd of November 2006 11:52:00 PM

    Outbreaks Show Bird Flu Virus Is Changing

    11.22.06, 12:00 AM ET



    WEDNESDAY, Nov. 22 (HealthDay News) -- Detailed data on clustered human cases of avian flu have experts agreeing that the H5N1 virus is evolving -- but in what direction?



    "The virus is always changing, and the mutations that make it more compatible with human transmission may occur at any time," warn Drs. Robert Webster and Elena Govorkova, both virologists at St Jude's Children's Research Hospital in Memphis, Tenn.



    Their commentary accompanies reports from Indonesia and Turkey, both published in the Nov. 23 issue of the New England Journal of Medicine.



    However, another expert believes that, so far, H5N1 has given no indication it is mutating toward human-to-human transmission.



    "It's far from a certainty," said Dr. Marc Siegel, a clinical associate professor of medicine at New York University School of Medicine, and author of Bird Flu: Everything You Need to Know About the Next Pandemic. "The virus could move closer to human-to-human transmission, and it could move farther away. I don't think that you can conclude from these articles in the NEJM that the thing is becoming easier to transmit."



    The two studies' most basic data is not new. They focus on three clusters of H5N1 infection in Indonesia in mid-to-late 2005, involving four deaths, and an eight-patient cluster treated in the first weeks of 2006 at a hospital in far-eastern Turkey. Four of the Turkish patients died.



    Details published in the journal do point to some intriguing trends, however.



    As noted in other cases, almost all infections were linked to close handling of domestic fowl. More troubling was the fact that the Turkish group, led by Dr. Ahmet Oner, of Yuzuncu Yil University, in Van, found it very difficult to diagnose H5N1 in humans at its earliest stages.



    Two standard tests turned up negative for the virus, and only a high-tech "polymerase-chain-reaction assay" confirmed H5N1 as the culprit. Infection also "causes a wide spectrum of illnesses in humans," the study authors wrote, with symptoms varying widely among patients.



    In the Indonesian report, led by epidemiologist Dr. Timothy Uyeki of the U.S. Centers for Disease Control and Prevention, researchers found that H5N1 affected some patients more severely than others, suggesting that there are genetic factors influencing patient vulnerability. They also noted that certain drugs, such as oseltamivir (Tamiflu), could help fight the predominant Indonesian strain, but these drugs are only effective when given a day or two after infection. That's probably too early for most patients, however.



    "In the countries that have reported human H5N1 cases, patients generally do not seek medical care early in their illness," Uyeki explained. "They usually present for medical care when their illness is advanced, e.g., they have pneumonia, and therefore they are not able to receive early oseltamivir treatment."



    In their commentary, Webster and Govorkova noted that the number of documented human cases of H5N1 infection is rising worldwide. A total of 251 cases have been recorded globally since 1997, they said, and "by mid-August, 97 humans had been infected in 2006 -- the same number as in all of 2005."



    No definite case of human-to-human transmission has yet been reported, suggesting that "the current H5N1 virus is apparently not well 'fitted' to replication in humans," the two experts wrote. However, "the intermittent spread to humans will continue, and the virus will continue to evolve," they added. "Clearly, we must prepare for the possibility of an influenza epidemic."



    Siegel believes this kind of language can be misleading.



    "We don't know enough about H5N1, and the science hasn't evolved to the point where we can predict when an epizoonotic problem -- a disease that has killed a lot of birds -- is going to start killing a lot of humans," he said.



    And, while reports do suggest a rise in human cases over time, Siegel noted that, prior to 1997, no one was keeping close tabs on the epidemiology of H5N1. "I think there may have been previous clusters that might have gone unreported because of a lack of attention -- they may have been misdiagnosed as other kinds of flu," he explained.



    Underreporting of prior outbreaks means it also impossible to say that the avian flu is mutating in any one direction, Siegel said. "There's just no way of telling from these clusters that this virus is evolving in the direction of easier transmission -- we can't tell if these clusters are anything new, or if there was a precedent for them," he said.



    Finally, he said, H5N1's genetic "leap" to human-to-human transmission -- if it ever happens -- will be much tougher than media reports have let on.



    "I've talked to a top expert at the U.S. National Institutes of Health," Siegel said. "He has tried to manipulate H5N1 to make it transmit more easily human-to-human, and he hasn't been able to do it. He's tried different mutations, including using proteins from the 1918 Spanish flu."



    While that doesn't mean the right combination of random mutations won't happen in the natural world, it suggests that a bird flu pandemic is a possibility -- but not a certainty. "There's no sense of 'imminence' here," Siegel said.



    All of the experts agreed that more needs to be done to curb the spread of the virus among birds, however.



    "H5N1 viruses are a 'moving target' and are evolving globally," Uyeki said. "Therefore, what is needed is ongoing, expanded surveillance of highly pathogenic avian influenza A (H5N1) viruses in animals (including poultry and wild birds) and humans in many countries."



    Webster and Govorkova noted that countries that have implemented tough, bird-focused interventions did reduce the threat. But with winter approaching, they worry that H5N1 will finally make its way from Eurasia to the Americas via migrating flocks.



    However, Siegel said, vaccinating every bird in the United States does not make sense right now. That's because the virus would simply go "underground," infecting fowl but not producing outward symptoms.



    "You want to vaccinate susceptible populations, and then control outbreaks by killing affected birds," Siegel said.



    But he also stressed that, "here, in the U.S., we as yet have no birds that have this virus. We don't even have a problem yet, except for fear."



    More information



    There's more on bird flu at the U.S. Centers for Disease Control and Prevention.


    From Research This Blog Entry

    UNH gets $1.55M for avian flu study

    Wednesday 22nd of November 2006 11:48:00 PM

    11-23-2006



    UNH gets $1.55M for avian flu study





    DURHAM -- An international, interdisciplinary team of researchers led by professor Xiangming Xiao of the University of New Hampshire is taking a scientific approach in an attempt to understand the ecology of the avian influenza, develop better methods of predicting its spread and provide an accurate early warning system.



    Xiao and colleagues were recently awarded $1.55 million for a four-year project funded by the U.S. National Institutes for Health as part of the Ecology of Infectious Diseases Program jointly sponsored with the U.S. National Science Foundation. The EID program supports research projects that develop quantitative analysis and modeling capacity for better understanding the relationship between manmade environmental change and the transmission of infectious agents.



    The UNH project will use environmental remote sensing data from Earth-observing satellites in combination with research in epidemiology, ornithology and agriculture to provide a better picture of how the Highly Pathogenic Avian Influenza survives and gets transmitted among poultry and wild birds. The work focuses on China, where outbreaks of the virus have been prominent.



    Xiao, of the UNH Institute for the Study of Earth, Oceans and Space Complex Systems Research Center, is the principal investigator for a team that includes scientists from the United Nations Food and Agriculture Organization and research institutes in Belgium and China. Research scientist Rob Braswell is a co-investigator.



    The ecology of the avian influenza involves a complex web of factors, including environmental settings, agricultural practices of rice production and harvesting, poultry production involving huge populations of free-grazing ducks and the migratory behavior of wild bird populations. Depending on how all of these risk factors intermingle over time, the virus can be spread through the environment by infected wild birds or domestic poultry.



    "The strength of our group, and of this proposal, is that over the last few years we've been able to pull a lot of information out of satellite observations that can help unravel the complex risk factors involved in avian flu ecology," said Xiao.



    For example, using imagery from satellites, the team can map and track the times when crops are planted and harvested and monitor activity in wetlands. Used in conjunction with other data of the environment, bird migration and poultry production, dynamic maps of "hot spots" and "hot times" for viral transmission can be developed and will aid the public, researchers, business and decision-makers in preparing for a potential pandemic crisis.



    This page has been printed from the following URL:

    http://www.seacoastonline.com/news/11222006/nhnews-ph-dur-unh.bird.flu.htm l



    Copyright 1999 - 2004 Seacoast Newspapers, a division of Ottaway Newspapers Inc., all rights reserved.


    From Research This Blog Entry

    What is bird flu?

    Tuesday 21st of November 2006 08:50:00 PM

    What is bird flu?



    Last Updated: 12:01am GMT 21/11/2006



    What is bird flu?



    Avian influenza or 'bird flu' is a contagious disease of birds, caused by influenza A viruses that can cause a range of symptoms, from mild illness and low mortality to a highly contagious disease with a near 100% fatality rate. The bird flu virus currently affecting poultry and some people in Asia and other areas is the highly pathogenic H5N1 strain of the virus.



    How is it spread?



    As the virus can remain viable in contaminated droppings for long periods, it can be spread among birds, and from birds to other animals, through ingestion or inhalation. All bird species are thought to be susceptible to avian influenza. Migratory birds such as wild ducks and geese can carry the viruses, often without any symptoms, and show the greatest resistance to infection. Domestic poultry flocks, however, are particularly vulnerable to epidemics of a rapid, severe and fatal form of the disease.



    What kind of virus is it?



    There are many different subtypes of influenza A virus. The most virulent are called highly pathogenic avian influenza and can reach epidemic levels among birds. Of these, subtype H5, and more particularly subtype H5N1, pose the greatest concern for human health. According to the World Health Organization (WHO), there is mounting evidence that the H5N1 strain has a unique capacity to jump the species barrier and cause severe disease, with high mortality, in people.



    How did the current outbreak start?



    The outbreak of avian influenza of most concern - H5N1 - began in poultry in South Korea in mid-December 2003, and has affected birds in many countries in Asia, Europe, Middle East and Africa. It involves a variant of the same virus subtype as that associated with the 1997 Hong Kong outbreak.



    How can bird flu infect people?



    H5N1 is able to infect people although it does not do this easily. In human populations, where domestic pigs and wild and domestic birds live in close proximity with people, the mingling and exchange of human and animal viruses can more easily occur. Those who have become infected have had close direct contact with infected birds.



    What symptoms does it cause?



    Human infection with avian influenza viruses usually causes conjunctivitis (eye infection) and mild flu-like symptoms, with one notable exception, the highly pathogenic H5N1 virus which can be deadly. The first documented cases in people appeared in Hong Kong in 1997, when 18 people infected with an H5N1 virus strain were admitted to hospital, six of whom died. As of 15 November 2006, 258 reported cases of H5N1 infection in people have occurred in ten countries, Thailand, Vietnam, Cambodia, Indonesia, China, Turkey, Iraq, Azerbaijan, Egypt, and Djibouti. One hundred and fifty-three of these have been fatal.



    Risk of a human influenza pandemic



    "We do not know what the virus is that will cause pandemic 'flu. What we do know is that Mother Nature has the recipe book and its just a matter of time before she starts cooking,." said Sir Liam Donaldson, Chief Medical Officer. "Wherever in the world a flu pandemic starts, perhaps with its epicentre in the Far East, we must assume we will be unable to prevent it reaching the UK. When it does, its impact will be severe in the number of illnesses and the disruption to everyday life."



    What is a pandemic, and what causes it?



    We are used to epidemics of 'ordinary' flu, which occur seasonally, every year, around the world. An epidemic is a widespread outbreak of disease occurring in a single community, population or region. A pandemic, on the other hand, occurs on a much greater scale, spreading around the world and affecting many hundreds of thousands of people across many countries.



    Three influenza pandemics occurred in the last century - 1918 to 1919 (Spanish flu), 1957 to 1958 (Asian flu) and 1968 to 1969 (Hong Kong flu). All affected large numbers of the population, causing many deaths and huge economic and social disruption. In the case of the 1918 outbreak, around 50 million people are thought to have died.



    What are the most important signals that a pandemic is about to start?



    The most important warning signal comes when clusters of patients with clinical symptoms of a new influenza, closely related in time and place, are detected, as this suggests human-to-human transmission is taking place. For similar reasons, the detection of cases in health workers caring for H5N1 patients would suggest human-to-human transmission.



    Why are they worried about H5N1?



    The H5N1 virus is one of 16 different known subtypes of influenza virus. Experts fear that the H5N1 subtype could trigger the next pandemic for several reasons. Firstly, it has already demonstrated an ability to infect people and kill - one of the key characteristics of a pandemic strain. Secondly, the virus has the ability to mutate and acquire genes from viruses infecting other species. Experts are concerned that the virus could either: adapt, giving it greater affinity for humans, or; exchange genes with a human flu virus, thereby producing a completely new virus strain capable of spreading easily between people, and causing a pandemic. Alternatively the pandemic could arise from a strain of influenza A unrelated to H5N1.



    Why is this influenza virus called H5N1?



    Subtypes of influenza virus are named according to two specific proteins, hemagglutinin and neuraminidase, on the surface of the virus. Hemagglutinin allows the virus to "stick" to a cell and initiate infection, while neuraminidase enables newly formed viruses to exit the host cell. Currently, there are 16 known variants of hemagglutinin protein and 9 known variants of neuraminidase proteins. This particular subtype of influenza virus has hemagglutinin type 5 and neuraminidase type 1, so it is known as H5N1.



    If there was a flu pandemic, what could I do?



    You can reduce, but not eliminate, the risk of catching or spreading influenza during a pandemic by: covering your nose and mouth when coughing or sneezing, using a tissue when possible; disposing of dirty tissues promptly and carefully ? bag and bin them; avoiding non-essential travel and large crowds whenever possible; maintaining good basic hygiene, for example washing your hands frequently with soap and water to reduce the spread of the virus from your hands to your face, or to other people; cleaning hard surfaces (e.g. kitchen worktops, door handles) frequently, using a normal cleaning product; making sure your children follow this advice.



    Are drugs effective in treating avian influenza in humans?



    The recently circulating H5N1 strains are susceptible to two antiviral drugs ?oseltamivir (sold as Tamiflu) and zanamivir (sold as Relenza). However, these medicines need to be started early enough?usually within the first two days of infection?to be effective. Many of the recently circulating H5N1 influenza viruses have been shown to be resistant to two older, inexpensive antiviral drugs, rimantadine and amantadine. Scientists are studying how the H5N1 viruses became resistant to these older drugs and watching for any signs of resistance to the newer drugs.



    What is the status of vaccine development and production?



    Vaccines effective against a pandemic virus are not yet available. Vaccines are produced each year for seasonal influenza but will not protect against pandemic influenza. Although a vaccine against the H5N1 virus is under development in several countries, no vaccine is ready for commercial production and no vaccines are expected to be widely available until several months after the start of a pandemic.



    Some clinical trials are now under way to test whether experimental vaccines will be fully protective and to determine whether different formulations can economize on the amount of antigen required, thus boosting production capacity. Because the vaccine needs to closely match the pandemic virus, large-scale commercial production will not start until the new virus has emerged and a pandemic has been declared. Current global production capacity falls far short of the demand expected during a pandemic.



    Is the world adequately prepared?



    No. Despite the advance warning the world is ill-prepared to defend itself during a pandemic. The World Health Organisation has urged all countries to develop preparedness plans, but only around 40 have done so. WHO has further urged countries with adequate resources to stockpile antiviral drugs nationally for use at the start of a pandemic. Around 30 countries are purchasing large quantities of these drugs, but the manufacturer has no capacity to fill these orders immediately. On present trends, most developing countries will have no access to vaccines and antiviral drugs throughout the duration of a pandemic.



    Sources: Department of Health, National Institutes of Health, World Health Organisation



    Information appearing on telegraph.co.uk is the copyright of Telegraph Media Group Limited and must not be reproduced in any medium without licence. For the full copyright statement see Copyright


    From Research This Blog Entry

    Britain vulnerable to drug-resistant bird flu

    Monday 20th of November 2006 11:17:00 PM

    Britain vulnerable to drug-resistant bird flu

    By Roger Highfield, Science Editor
    Last Updated: 2:07am GMT 21/11/2006

    # The report: Pandemic influenza: science to policy
    # Q&A: What is bird flu?

    The nation has been left vulnerable to a global bird flu pandemic because the stockpile of anti virus drugs is deficient, leading doctors and scientists have warned.

    Only a few days after MPs criticised the way politicians abused scientific research, a report warns that the Government is not making best and timely use of independent scientific advice in preparing for an influenza pandemic, when an avian strain of influenza develops the means to spread among people and kill millions worldwide.

    The report by the Royal Society and the Academy of Medical Sciences, published today, recommends that the Department of Health urgently revisits its decision to stockpile only one antiviral drug ? Tamiflu ? in light of emerging scientific evidence that the avian flu virus known as H5N1, can develop resistance to this drug.

    The Government has ordered 14.6 million courses of Tamiflu, which could cover one quarter of the population.

    Leaving aside issues of how to use Tamiflu effectively, how much drug will be required to treat infections, and whether it should also be used to prevent infections, Prof Neil Ferguson, from Imperial College London, said that the emergence of a Tamiflu-resistant pandemic strain is a "nightmare scenario" for which the UK needs to be prepared.

    Stocking the alternative - inhaled - antiviral Relenza, alongside Tamiflu, which is taken in tablet form, could provide an important second line of defence in the event of a pandemic, as in other countries, because "not all viruses that are resistant to Tamiflu are resistant to Relenza," said Sir John Skehel, chair of the report's working group.

    "The Government was right to order Tamiflu in early 2005," he said. "However, we are concerned that it is not updating its plans as the landscape of what we know about influenza changes.

    This shortcoming illustrates how "we are concerned that decisions are being made, as the UK prepares for a possible pandemic, that fail to take account of expert advice," he said.

    The Department of Health ordered two pandemic vaccines on the basis of preliminary data and no human or animal trial data, according to the report, which calls on samples to be made available to scientists for testing as soon as possible and for more openness: "The working group found difficulty in penetrating the barrier of confidentiality that surrounds the industry and its relationship with the Department of Health."

    The report recommends the appointment of a leading influenza specialist as a high-level independent adviser to government, a Flu Czar, to feed the latest scientific information from academic researchers, industry and government departments into the ministerial committee which is responsible for preparing for a pandemic.

    The report also calls on the Department of Health to bring together academic researchers and those in pharmaceutical companies to develop and improve vaccines ? which will be a fundamental tool to control the scale of an influenza pandemic.

    The report highlights that it would not be possible to manufacture enough influenza vaccines globally in a pandemic. However, limited supplies can "go-further" if combined with compounds known as "adjuvants" which increase vaccine effectiveness.

    Improving vaccine performance with these compounds will help overcome the challenges of producing sufficient H5N1 vaccine against the particular virus that may hit the UK. "Encouraging researchers and drug manufacturers to share information would speed up the development of adjuvants and vaccines to make the UK more responsive during a pandemic," the report says.

    And it says that the Government should consider "population priming" where, even without an exact match in virus strain, it may be possible to provide broad immunity by vaccinating with a pre-pandemic influenza vaccine.

    So far this year, there have been 75 deaths caused by the H5N1 virus, compared with 42 last year, and there are still widespread concerns that it could mutate or combine to make a superflu capable of causing a global pandemic.

    Prof Lindsey Davies, the Department of Health's Director of Pandemic Influenza Preparedness, said: "We are already addressing many of the report's recommendations in our ongoing pandemic preparedness planning."

    Information appearing on telegraph.co.uk is the copyright of Telegraph Media Group Limited and must not be reproduced in any medium without licence. For the full copyright statement see Copyright


    From Research This Blog Entry

    Bird Flu Vaccine Has Short Shelf Life

    Saturday 18th of November 2006 06:31:00 PM

    NOVEMBER 18, 2006 | SAN DIEGO, CA

    KFMB STATIONS: News 8 | 100.7 JACK FM | 760 KFMB



    Bird Flu Vaccine Has Short Shelf Life



    Last Updated:

    11-18-06 at 2:24PM



    WASHINGTON -- Some of the first doses of bird flu vaccine in the nation's stockpile are growing weaker with age. If the shots are needed anytime soon, there will be enough for a million fewer people than previously thought.



    More up-to-date vaccine is being brewed to supplement the supply, which today has enough full-strength shots to vaccinate about 3 million people, according to an update issued this week by Health and Human Services Secretary Mike Leavitt.



    Last summer, HHS officials were estimating that the stockpile had enough vaccine for 4 million people.



    All vaccines lose potency if they spend enough time sitting on the shelf unused. Sure enough, routine testing uncovered that that has begun to happen with some of the first-brewed vaccine against the deadly Asian bird flu known as H5N1, HHS spokesman Bill Hall said Friday.



    The government is stockpiling antiflu medications and a small amount of H5N1 vaccine in case the bird flu or some other super-strain sparks the next influenza pandemic. Here's the rub: If such a super-flu began circulating, it would take several months to begin brewing vaccine that was an exact genetic match. But the hope is that if H5N1 were the culprit, health workers and certain other people at high risk might get some protection from shots made against earlier strains of that virus.



    The first batches in the nation's stockpile were brewed using an H5N1 strain that circulated in 2004. Now, manufacturers are brewing vaccine using a newer strain that circulated in Indonesia last year. With that updated version, HHS expects to have enough shots for another 5 million people sometime next year.



    Meanwhile, the older shots' loss of strength is gradual, raising the question of whether some subpotent doses might be able to be used if absolutely necessary, Hall noted. "It doesn't go from 100 percent to zero," he said.



    Copyright © 2006 Midwest Television


    From Research This Blog Entry

    OSHA Updates Avian Flu Guidance

    Saturday 18th of November 2006 06:27:00 PM

    OSHA Updates Avian Flu Guidance

    November, 16 2006

    Updated guidance from OSHA for occupational exposure to the H5N1 virus ? avian flu ? focuses on good hygiene, including use of gloves and hand washing, as well as respiratory protection for those who work with infected animals or individuals.



    By Josh Cable



    "We encourage employers and employees who are most likely to be exposed to avian flu to take the appropriate precautions," OSHA Administrator Ed Foulke Jr. said. "This guidance offers them practical tips, such as hand washing and the use of proper protective equipment, for preventing illness."



    The new document ? OSHA Guidance Update on Protecting Employees from Avian Flu Viruses ? updates guidance on avian flu issued by OSHA in 2004.



    The update provides separate recommendations for poultry employees and those who handle other animals, and for laboratory employees, health care personnel, food handlers, travelers and U.S. employees stationed abroad.



    The guidance also includes links to helpful Web sites with additional information, and a list of technical articles and resources, including a history on flu pandemics, symptoms and outcomes of various strains of the avian flu, a summary of the bird importation regulations and details on the transmission of the virus.



    Avian Flu Could Be the Next Flu Pandemic



    Wild birds, particularly waterfowl, are natural hosts of avian flu viruses and often show no symptoms; however, some of the viruses can cause high mortality in poultry, including the H5N1 virus.



    Some strains of avian flu viruses carried by these wild birds can infect domestic fowl and in turn can infect humans, causing fever, cough, sore throat, eye infections and muscle pain. Avian flu can also lead to pneumonia, acute respiratory distress, and other severe and life-threatening complications. The most common route of transmission to humans is by contact with contaminated poultry.



    The federal government is providing funding, advice, support and up-to-date information to help Americans prepare for and prevent the spread of avian flu in this country. The world's public health community is concerned that a new avian flu subtype may acquire the capability of human-to-human transmission, and become an agent for the next flu pandemic.



    Increasing concern over the possibility of a pandemic has led the World Health Organization to develop a Global Influenza Preparedness Plan, and the White House to issue its National Strategy for Pandemic Influenza.



    OSHA Guidance Available on Agency's Web site



    OSHA Guidance Update on Protecting Employees from Avian Flu Viruses, as well as other important information on the topic, is available in English and Spanish by visiting the In Focus section on the home page of OSHA's Web site or by clicking here.



    For more information on federal activities on avian flu and pandemic flu, visit http://www.pandemicflu.gov.



    Occupational Hazards | Copyright © 2006 Penton Media, Inc. All Rights Reserved.


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