Avian flu in perspectiveNovember 28, 2005Saint Louis University influenza researcher comments in Nov. 24 issue ST. LOUIS - An article by Robert Belshe, M.D., of Saint Louis University School of Medicine in this week's New England Journal of Medicine reviews recent "spectacular achievements of contemporary molecular biology" that hold great importance as the world prepares for a possible flu pandemic. These achievements, including a recent genetic sequencing and recreation of the virus from the 1918 flu pandemic, "may enable us to track viruses years before they develop the capacity to replicate with high efficiency in humans," Belshe writes. The new knowledge of the genetic sequences of influenza viruses that predate the 1918 epidemic will be "extremely helpful in determining the events that may lead to the adaptation of avian viruses to humans before the occurrence of pandemic influenza." And as the virus continues to adapt, scientists now know what to look for. Belshe said scientists should conduct worldwide surveillance to monitor this adaptation process. "It gives us some reassurance that by continuing to monitor the current virus in birds, we can get a sense as to when it'll be an efficient virus," Belshe says. "We may have some time to develop new vaccines and better therapies." Belshe reviews recent articles in Science and Nature as part of his perspective article "The Origins of Pandemic Influenza â€" Lessons from the 1918 Virus." The lead author of the research in Nature was Jeffery Taubenberger, M.D., Ph.D., of the U.S. Armed Forces Institute of Pathology, and the research in Science was led by Terrence Tumpey, Ph.D., of the Centers for Disease Control and Prevention. "These recent research findings involving avian flu are startling, and they tell us that there are at least two mechanisms by which a pandemic influenza epidemic could emerge," Belshe says. "This research provides critically important insight into the origin of pandemic influenza." Both mechanisms described in the articles were observed during worldwide pandemics of the 20th century. Scientists now conclude that the prospect of a new worldwide pandemic during the 21st century could involve either of two possibilities: - A direct spread of an entirely avian virus from birds to humans. This is what happened during the 1918 Spanish flu, the deadliest of last century's three pandemics. - A "reassortment" virus that mixes bird flu with already circulating human influenza strains to create a new strain. This was the case during the 1968 Hong Kong flu pandemic and the 1957 Asia flu pandemic. (Most of the flu strains of today are genetically related to the 1968 outbreak, which as a reassortment virus is genetically related to both the 1957 and 1918 viruses.) Belshe said the question of the moment involves which mechanism a future pandemic could involve. "Are we going to see an event like 1918, an avian virus adapting to man, or will it be an event like 1957 or 1968, where an avian virus contributes some genetic material by mixing in with a current strain of the human virus?" Belshe says. "We don't know what will happen or when it will happen, but we know it will happen." And although it can't be said for sure whether the current avian flu virus can adapt readily to the point where human-to-human transmission is possible, the recent research findings do provide some clues as to what genetic changes are necessary for such an event to occur. In fact, several additional genetic changes must occur in the currently circulating bird flu viruses before these viruses will begin to spread efficiently from person to person and this can be monitored closely by scientists. "Taubenberger estimated that based upon the rate of evolution, the 1918 epidemic had circulated in man since 1900," Belshe says. "So it took a while to become highly efficient as a pandemic virus.\\\ Saint Louis University |
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| Related Flu Pandemic Current Events and Flu Pandemic News Articles Sneezing in times of a flu pandemic The swine flu (H1N1) pandemic has received extensive media coverage this year. The World Health Organization, in addition to providing frequent updates about cases of infection and death tolls, recommends hyper vigilance in daily hygiene such as frequent hand washing or sneezing into the crook of our arms. Lessons from flu seasons past Pregnant women who catch the flu are at serious risk for flu-related complications, including death, and that risk far outweighs the risk of possible side effects from injectable vaccines containing killed virus, according to an extensive review of published research and data from previous flu seasons. Older Patients with Dementia at Increased Risk for Flu Mortality An epidemiological study on pneumonia and influenza (P&I) in adults age 65 and over reports that patients with dementia are diagnosed with flu less frequently, have shorter hospital stays, and have a fifty percent higher rate of death than those without dementia. Triple-Combo Drug Shows Promise Against Antiviral-Resistant Swine Flu, UAB Researcher Says An experimental drug cocktail that includes three prescriptions now widely available offers the best hope in developing a single agent to treat drug-resistant H1N1 swine flu, says a virology researcher in the University of Alabama Birmingham (UAB) Division of Pediatric Infectious Diseases. Medical ethics experts identify, address key issues in H1N1 pandemic The anticipated onset of a second wave of the H1N1 influenza pandemic could present a host of thorny medical ethics issues best considered well in advance, according to the University of Toronto Joint Centre for Bioethics, which today released nine papers for public discussion. Texas A&M researcher shows possible link between 1918 El Niño and flu pandemic Research conducted at Texas A&M University casts doubts on the notion that El Niño has been getting stronger because of global warming and raises interesting questions about the relationship between El Niño and a severe flu pandemic 91 years ago. 'Dung of the devil' plant roots point to new swine flu drugs Scientists in China have discovered that roots of a plant used a century ago during the great Spanish influenza pandemic contains substances with powerful effects in laboratory experiments in killing the H1N1 swine flu virus that now threatens the world. NIAID scientists study past flu pandemics for clues to future course of 2009 H1N1 virus A commonly held belief that severe influenza pandemics are preceded by a milder wave of illness arose because some accounts of the devastating flu pandemic of 1918-19 suggested that it may have followed such a pattern. Avian influenza strain primes brain for Parkinson's disease At least one strain of the H5N1 avian influenza virus leaves survivors at significantly increased risk for Parkinson's disease and possibly other neurological problems later in life. Flu mortality formula is potentially misleading, say scientists A standard calculation used in forecasting potential numbers of deaths during the swine flu pandemic risks misleading healthcare planners by being open to both over- and under-estimation of the true figures. More Flu Pandemic Current Events and Flu Pandemic News Articles |
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