Swine flu could infect up to half of the U.S.

Epidemic could kill 30,000 to 90,000 By Steve Sternberg • USA TODAY • August 25, 2009 The global flu pandemic expected to return to the United States this fall is likely to infect as much as half of the population, flooding hospitals with nearly 2 million patients and causing 30,000 to 90,000 deaths, according to the first official prediction of the scope of the coming epidemic. The report, released Monday by the White House, was prepared by the President's Council of Advisors on Science and Technology beginning in late June at President Barack Obama's request. It concludes that the expected resurgence of the new form of H1N1 flu, also known as swine flu, "poses a serious health threat to the United States." While this is not the 1918 flu pandemic, it infects younger people more and serious complications do occur," says the panel's co-chairman Eric Lander, director of the Broad Institute of Harvard and MIT, warning that infants and children, pregnant women, older adults, and people with chronic illnesses are at special risk of serious complications. As of Aug. 15, swine flu has caused 7,983 hospitalizations and 522 deaths in the U.S., according to the U.S. Centers for Disease Control and Prevention. But flu experts worry that the number of cases is likely to mount as more children and young people return to school and as colder weather drives more people to congregate indoors. We think it's very likely cases will increase," says David Marens, a flu expert at the National Institute of Allergy and Infectious Diseases. Unlike previous analyses, the White House science advisors drew from experience with past pandemics to attempt to forecast the impact of the 2009-2010 H1N1 flu and use the information to guide the nation's response to the epidemic. The report concludes that the coming flu season will more likely resemble the flu pandemic of 1957, which killed 70,000 people in the USA, or 1968, when 34,000 died. It is unlikely to have the tidal impact of the 1918 flu, which killed more than 500,000 people in the USA and more than 50 million people worldwide. About 36,000 people die annually in the U.S. from seasonal flu strains. Marens says some features of the flu pandemic may help to blunt its impact, especially the fact that it appears to spare the elderly who usually die in the greatest numbers during flu pandemics. Timing may help too, he says. "It came at a time of the year when influenza viruses have trouble getting traction. That bought us a lot of time to figure this out and make a vaccine. And as the virus has spread this summer it hasn't been so bad. These are good things. It doesn't necessarily mean we're out of the woods, but at least they're not bad news." Public health experts have faced the dual challenge of preparing for two parallel flu epidemics ever since swine flu emerged in Mexico in April. The world's five vaccine makers rushed to finish the vaccine for seasonal flu, which is now being distributed, and to begin formulating a pandemic flu vaccine. The federal government has ordered 190 million doses; about 40 million are expected to be available by mid-October. White House science advisors express concerns that, without significantly accelerating flu vaccine production, the first doses of vaccine may become available after the swine flu season peaks in October. They also assert that the influx of patients may tie up hospital emergency rooms and intensive-care units (ICUs). "It's possible that at a time of peak demand from 50 to 100 percent of ICU beds in an area might be used for influenza cases. They're often close to capacity without influenza," Lander says.