are you tired of hurricanes, wildfires and the threat of nuclear war?
Posted by
x (aka dmuck)
Oct 19 '17, 12:51
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if so, can i interest you in a possible pandemic?
"The Centers for Disease Control and Prevention (CDC) keeps a Most Wanted list for flu viruses. The agency evaluates every potentially dangerous strain, and gives them two scores out of 10—one reflecting how likely they are to trigger a pandemic, and another that measures how bad that pandemic would be. At the top of the list, with scores of 6.5 for emergence and 7.5 for impact, is H7N9.
Influenza viruses come in many flavors—H5N1, H1N1, H3N2, and so on. The H and N refer to two proteins on their surface, and the numbers refer to the versions of those proteins that a particular virus carries. H1N1 was responsible for both the catastrophic pandemic of 1918 that killed millions of people, and the most recent (and much milder) one from 2009. H5N1 is the bird-flu subtype that has been worrying scientists for almost two decades. But H7N9? Until recently, it had flown under the radar.
H7 viruses infect birds, and only very rarely jump into humans. H7N9 in particular had never been known to infect humans at all before 2013, when it caused an unexpected epidemic in China. It was billed as low-pathogenic (or “low-path”) because it only caused mild disease in chickens. But in humans, the story was different: Of the 135 people infected, around a quarter died.
Every year since, there’s been a new epidemic, and the current one is the worst. H7N9 has evolved, acquiring mutations that allow other flu strains to reproduce more effectively in both birds and mammals. It has started killing birds. In one year, H7N9’s highly pathogenic (“high-path”) strains have caused as many human infections as the previous four epidemics put together. As of September 20, there have been 1,589 laboratory-confirmed cases, and 39 percent of those people have died. “It was a matter of time,” says the flu expert Yoshihiro Kawaoka, from the University of Wisconsin-Madison. “It wasn’t surprising to see this change.”
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