Head lice are as likely to infest a clean head as an unwashed one.

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It predates the dinosaur by 150 million years, and today no fewer than 5, 000 species infest the Earth.

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Then there are robbers who infest the roads, and a body of police must be kept up, etc.

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The larvae of these tiny insects infest ripe fruits, making them unsellable.

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"Rodents can infest a whole range of these structures, " Kramer said.

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Bergy bits, growlers and brash ice infest many bays.

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The U.S. Supreme Court did that 30 years ago in the context of federal regulations, finding the chief executive of a 30, 000-employee grocery chain liable for allowing rodents to infest a Baltimore warehouse.

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