LOS ANGELES (AP) - California health officials say a ninth baby in the state has died from whooping cough.
California Department of Public Health spokesman Ken August told the Los Angeles Times Tuesday that the death makes this year's epidemic more deadly than one in 2005.
Officials say the baby lived in San Bernardino County and was less than two months old.
Whooping cough, also called pertussis, is a bacterial infection that causes severe coughing spells. It can be tough to diagnose because early symptoms are mild and resemble a cold. Since whooping cough can progress rapidly in infants, delayed treatment can increase the risk of death.
Some 3,600 whooping cough infections have been reported in California so far this year - a sevenfold jump from the same period last year and the most cases since 1958.
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