First, unlike smallpox, polio viruses can survive for long periods outside a host for instance in sewage.

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Take, for instance, the host of other celebrity endorsers including Lady Gaga, Diddy and LeBron James.

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The Yankees, for instance, will host the Los Angeles Dodgers for the first time in the regular season next month a matchup with a little more buildup than this (not very much) anticipated White Sox-Mets showdown.

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We have emerging partnerships with a whole host of nations -- for instance, he'll be doing the ASEAN meeting.

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Down the line, Foursquare hopes building up a base of active users will give it options for bringing in revenue, for instance by charging merchants to host discounts or sharing revenue with AmEx or another credit-card company.

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An alien bug that causes diarrhoea, for instance, is as much an enemy of the microbiome as of the host.

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This fall, for instance, the Boulder Theater, near the University of Colorado, will host the Psychedelic Furs, Aimee Mann, and Dinosaur Jr.

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Ratings-troubled CNN, for instance, could surely use the help of the once top-rated MSNBC host as it looks to reinvent itself under new management.

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For instance, Sydney is the first Olympics in which NBC is in competition with the host city to find advertisers for their respective Web sites.

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