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California suffers its worst pertussis outbreak in 63 years, with close to 8,000 people possibly infected in 2010, according to a Dec. 15 report from the California Department of Public Health. Also known as whooping cough, pertussis is caused by a bacterium called Bordetella pertussis. This year, it proves especially deadly to infants, 10 of whom perish from it. State officials urge increased vaccination against the disease.
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