阅读理解
It was just a footnote compared with the more infectious disaster that killed millions more people in 1918, but the 1957 influenza pandemic that sickened some 25 to 30 percent of the American population was a medical watershed for the clues that it offered about how a new strain of influenza could spread. Americans first got a whiff of the so-called Asian flu when Maurice Hilleman, a physician at Walter Reed Hospital in Washington, D.C., read about an unusually large number of people—some 250,000—who had come down with flu-like symptoms in Hong Kong. Concerned, he immediately requested samples from American servicemen in Asia and within days had his answer. The genetic structure of this strain was like nothing immunologists had ever seen before. When the virus finally hit America: "It went like a house on fire," recalls D. A Henderson, then the chief of the United States Epidemic Intelligence Service. Worsened by school openings that fall, the flu spread so rapidly from a few counties in Louisiana that just eight weeks later it had heavily infected more than half the counties in nearly all 50 states. Although it wasn't particularly potent, the 1957 strain killed about 80,000 Americans. The victims were predominantly the very old and the very young, although the infection occasionally killed otherwise healthy adults as well. Pharmaceutical companies worked furiously to produce a vaccine, ultimately distributing some 40 million doses. But "they were just a little bit too late," says Arnold Monto, an influenza specialist at the University of Michigan. "They only had significant doses available when the pandemic was peaking." Earlier, scarcities raised questions about who deserved the vaccine first. A set of official rules gave priority to military personnel and necessary civic workers, but that didn't stop members of the San Francisco 49ers football team from getting vaccinated before police and firemen. Despite some manufacturing improvements, experts say the same shortages could occur with a pandemic today. And that concern has caused preparedness officials to plan for community interventions such as school closings and isolation of sick people. But Henderson says, "It won't work. And you don't need a better example than '57. When you go from just a few scattered outbreaks in the end of August to the whole country infected in eight weeks, at a time when people didn't travel as much as they do today and cities were not as densely populated, what do you think we're going to see today?" Better, he says, to have good vaccines and to ensure that the medical system can handle the extra load.
单选题11.The word "footnote"(Line 1, Paragraph 1)means that the influenza in 1957