A recent study published in the Spanish flu epidemic of 1918 February 5, 2004, in Science Express confirmed the online version of Science magazine suggests that our fears worse when it started in birds. The 1918 flu epidemic killed an estimated 20 million to 40 million people around the world, including at least 500,000 in the United States. The research was the result of a long-term collaboration between the late Don Wiley, a Howard Hughes MedicalInstitute researcher at Harvard University and Sir John Skehel of the Medical Research Council's National Institute for Medical Research in London.
The results are finally revealed the mechanism by which the murderess influenza infects human cells and was responsible for the deaths of many millions of young people to develop as many of the elderly population, a certain immunity to viruses similar earlier in their lives . The Spanish flu virus is now extinct, but researchersits viral DNA sequences were investigated by examining biopsies from infected tissue from the bodies of American soldiers died in the pandemic and Intuit woman whose body was preserved in permafrost in Alaska. The scientists used X-ray crystallography the three-dimensional structure of the surface haemagglutinin of the 1918 virus' (HA) protein, a molecule that is known to start to reveal the early stages of infection. The protein binds to receptors on the cell surface and causesHuman cells in the pores open, allowing the virus to pass.
The HA protein product for human and avian viruses bind normally to various types of cell receptors, which makes it very difficult to infect avian strains to humans and vice versa. The document showed that the molecule could still resemble the HA binding site bird flu, but infect humans, the researchers found that two pages of hemagglutinin receptor site in slightly different positions in1918 hemagglutinin, in comparison with the Hong Kong-protein, that bind to an antigen in the human receptor-positive way. This means that even during the 1918 pandemic, the avian influenza HA protein mutant seems, so that the deadly virus to bind efficiently to human cells, while maintaining the basic characteristics of the avian influenza virus from which emerged.
While some scientists have long argued that the Spanish flu had nothing to do with birds, many othersI suspect that it was a bird flu virus had mutated in some way and "jumped" from birds to humans. The report's findings are important because a strain of bird flu, H5N1, as is known, has recently spread like wildfire throughout Asia and has already killed 12 people. The hemagglutinin of the 1918 virus was H1, the Asian flu, which began in 1957 H2, and the strain in Hong Kong, which began in 1968, designated H3.
It is understood that many scientiststhe view that the potential pandemic in humans has become, if not stopped quickly. The WHO, UNFAO, and the World Organisation for Animal Health have jointly today an urgent appeal for funds for the new avian influenza, which they say could quickly into an "efficient and dangerous human pathogen", which is dedicated development. Many Asian countries have used mass culling of infected farms to be the best way to control the spread of pandemic influenza. This radical programinfluenced by a widespread feeling that health authorities in Asia quickly enough last year to the SARS virus, a hitherto unknown human pathogens that contain eventually killed 800 people, has failed. Apart from being highly contagious, influenza viruses have the ability to rapidly mutate by exchanging genes with each other, so if someone brings a new human flu virus catches the bird flu, the two strains in the body of a patient to combine, creating a new, highlycontagious and fatal human plague. And 'well known that the two influenza pandemics of 1957 and 1968 by mixing human and animal viruses, to form hybrids have been created.
Fortunately, as with the 1997 outbreak in Hong Kong, almost all patients who appear to have been infected with the H5N1 virus has infected through direct contact with infected birds. I am aware of the growing concern about two sisters who died of disease in Vietnam last month, which probably started fromhis brother. There were also concerns over five-year-old girl, 7 December 2003 the disease had approached chickens played, but his two young cousins, who were less than a week later in hospital, had only played in their vicinity . The WHO said that the current outbreak of H5N1 in birds started in South Korea in December, but many feel the outbreak probably began a few months before the farms of southern China, where ducks are often housed together with pigs andPeople.
There is no doubt that earthquakes in California, another global influenza pandemic is "inevitable and possibly imminent", but the world is a different place than the bad conditions that existed at the end of World War II. For starters there is now a global disease surveillance to warn us if H5N1 has begun to show evidence of direct person to person. We have better anti-viral drugs and treatments that are available for the many millions that have beensuccumbed to the pandemic during the past century. At best we can tell, that seems to present the transmission of the H5N1 virus from person to person can be inefficient, because every day on our television screens of workers, only instead of masks, gloves to kill the birds have been seen dead bodies in barrels .
Another study led by Ian Wilson of the Scripps Research Institute in La Jolla, California, was conducted recently published in Science, has confirmed that birds were the source of strain 1918. AlthoughNo cases of bird flu infecting humans, until an outbreak of H5N1 in poultry in Hong Kong in 1997, is now thought that all the worst flu outbreaks in the last century, including the Asian flu in 1968 and 1957 's Hong Kong flu birds from primary school.
Most of us remember that in 1997, six people have died after contact with infected birds and shoot down a decision in Hong Kong's entire poultry population of about 1.5 million birds in just three days. Rejectingthe influenza virus more opportunities to infect humans, it can act quickly to avert a pandemic. So let's just hope that we stop this epidemic of H5N1 in its present location, before being in another world problem.
Centers for Disease Control background on pandemics
An influenza pandemic is a worldwide epidemic of influenza and occurs when a new influenza virus emerges, spreads and causes disease worldwide. The influence of the pastPandemics have caused high levels of illness, death, social disruption and economic losses. There were three pandemics in the 20 st Century. All of them spread worldwide within 1 year of being detected. They are:
1918-19 "Spanish flu" [A (H1N1)] caused the highest number of known flu deaths: more than 500,000 people in the United States have died, and 20 to 50 million people died worldwide. Many people died in the first days after infection and diedof complications soon after. Almost half of those killed were healthy young adults.
1957-58 "Asian flu" [A (H2N2)] caused about 70,000 deaths in the United States. First identified in China in late February 1957, the Asian flu spread to the U.S. in June 1957.
1968-69, "Hong Kong flu" [A (H3N2)] caused about 34,000 deaths in the United States. This virus was diagnosed in Hong Kong in early 1968 and released in the U.S.by the end of the year. Type A (H3N2) viruses still circulate.
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