一本教会你“做对”题的6级阅读书 day3 passage1
Passage 1 The H1N1 Pandemic: Is A Second Wave Possible? 046
H1N1会卷土重来？ 《时代周刊》2009-12-10
[00:00]The H1N1 Pandemic: Is a Second Wave Possible?
[00:07]Since early November, cases of H1N1 have continued to decline nationwide,
[00:15]and scientists keeping track of the numbers say that as pandemics go,
[00:21]2009 H1N1 may turn out to be a mild one — at least for the time being.
[00:30]The question now on health officials' minds is:
[00:33]Will there be a second wave of cases in the new year?
[00:38]The answer depends on whom you ask.
[00:41]"We took an informal poll of about a dozen of some of the world's leading experts in influenza,
[00:48]" Dr. Thomas Frieden, director of the Centers for Disease Control and Prevention (CDC),
[00:55]told reporters recently. "About half of them said,
[00:59]Yes, we think it's likely that we'll have another surge in cases.
[01:04]About half said, No, we think it's not likely. And one said, Flip a coin."
[01:10]It is an accurate reflection of how unpredictable the influenza virus can be.
[01:18]Although flu activity has been declining for the third week in a row,
[01:23]health officials warn that there are still four to five months left
[01:29]in the official influenza season, plenty of time for the virus
[01:33]to make its rounds and find new hosts. "The story of pandemics,
[01:37]and the story of H1N1 in general, is the story of persistent uncertainty
[01:46]where we never quite know what we are going to get or when,
[01:51]" says Dr. Irwin Redlener, director of the National Center for Disaster Preparedness
[01:57]at the Columbia University Mailman School of Public Health.
[02:04]How severe the current H1N1 pandemic seems depends on what you use as a measuring stick.
[02:12]Compared with previous pandemics, like the 1918 Spanish flu, which killed 20 million people
[02:20]and infected up to 40% of the world's population,
[02:25]or even the far less deadly 1957 and 1968 outbreak with a strain of H1N1
[02:32]influenza similar to the 2009 strain, things don't seem as bad this time around.
[02:40]Fewer people are getting severely ill when infected, and fewer have died
[02:46]or required hospitalization from the flu than in previous pandemics.
[02:50]Marc Lipsitch, an epidemiologist at the Harvard School of Public Health,
[02:56]and his colleagues studied the course of the 2009 H1N1 pandemic last spring in two cities
[03:04]— New York and Minneapolis — and determined that 0.048% of people
[03:11]who developed symptoms of H1N1 died, and 1.44% required hospitalization.
[03:22]Based on that data, published in PLoS Medicine, Lipsitch anticipates far fewer deaths
[03:30]from 2009 H1N1 than was initially believed. By the end of the flu season in the spring of 2010,
[03:40]Lipsitch predicts, anywhere from 6,000 to 45,000 people will have died from H1N1 in the U.S.,
[03:49]with the number most likely to end up between 10,000 and 15,000.
[03:55]Those estimates are far below the death of the 1957 flu, which killed 69,800 people in the U.S.,
[04:05]according to government figures, and smaller also
[04:10]than the early predictions for the 2009 H1N1 flu deaths, which ranged from 30,000 to 90,000.
[04:18]It is not clear, however, that past pandemics are an appropriate measuring stick
[04:25]for evaluating the current flu or that the new predictions are based on complete data.
[04:31]The eventual deaths of 2009 H1N1 may be less grim than the outcomes of previous pandemics,
[04:39]but it should be noted that 90 years ago, and even 40 years ago,
[04:44]health officials lacked the antiviral therapies and nationwide vaccination capabilities
[04:51]that are available today. That may have contributed to pandemics having a more devastating
[04:59]effect on the health of past populations.
[05:02]The new estimates are also less alarming than those provided — also by Lipsitch —
[05:09]to the President's Council of Advisers on Science and Technology last summer
[05:14]near the start of the pandemic. At the time, researchers had only patchy data
[05:20]on the number of people infected by, and seeking treatment for, the new flu.
[05:26]The initially depressing prediction of the impact of H1N1 — with up to 50% of the U.S.
[05:33]population being infected in the fall and winter of 2009, resulting in as many as 90,000 deaths
[05:40]was based on modeling of previous pandemics.
[05:44]Fortunately, the worst case scene did not occur. "The worst case consistent
[05:52]with the data we have now is a lot milder than the worst case consistent with the data
[05:58]we had in the summer or spring," Lipsitch says.
[06:02]Still, Lipsitch and other health officials acknowledge that the 2009 H1N1 pandemic is not over.
[06:11]What worries health officials most is that as both seasonal and H1N1 flu viruses circulate
[06:21]among the population, the two strains could recombine into a more deadly and aggressive version
[06:26]that could cause more widespread illness and even death. How viruses behave
[06:33]once they setttle into a host is completely unpredictable,
[06:38]but scientists know that in a lab dish, seasonal and H1N1 flu strains mix and match readily.
[06:47]"I'm thinking we may have avoided a bullet here if in fact we don't get a more severe wave coming
[06:55]on the heels of the current wave," says Redlener. "But we'll see what happens."
[07:02]A second wave could still prove more deadly than the seasonal flu, especially for young children.
[07:10]To date, 189 children have died of influenza in the U.S.,
[07:17]the majority of them related to H1N1 infection, and that number is already higher
[07:24]than the total number of child deaths attributed to flu in 2008.
[07:30]Lipsitch says that if current trends hold, H1N1 may end up causing as many influenza deaths,
[07:39]if not more, than the seasonal flu, which kills about 36,000 Americans each year.
[07:45]Instead of hitting the elderly the hardest, though,
[07:51]most of the deaths may be among young children and infants.
[07:57]According to the most recent CDC estimates, released by health officials Thursday,
[08:04]about 10,000 Americans have died from H1N1 and 50 million — or one-sixth of the population —
[08:14]have been infected. The CDC says also that about 200,000 people have been sick
[08:22]enough to require hospitalization, and that most of them were adults under age 65.
[08:30]The new figures cover the first seven months of the pandemic, from April through mid-November,
[08:36]and represent a large increase over the previous estimates, which included data through mid-October
[08:44]and said H1N1 had killed 4,000 and infected 22 million.
[08:52]But experts said the jump was not surprising,
[08:55]given that the current wave of disease was peaking in early November.
[09:02]The looming concern over another winter wave of flu is all the more reason, says Lipsitch,
[09:09]to continue aggressive antiflu efforts, from washing your hands to covering your cough
[09:15]and getting vaccinated. In some states, including New York, there is now enough vaccine
[09:24]to vaccinate everyone over six months old, and not just those in priority groups.
[09:30]"We would expect that prior exposure to a similar strain in the form of a vaccine will provide
[09:37]some priming for future exposures, even if the virus changes a bit," says Lipsitch. In other words,
[09:47]the more people who are vaccinated this year, the less likely the H1N1 virus,
[09:54]which will probably still be around next year, will take hold and spread.
