"We are off to a really bad start in 2014," said state epidemiologist Gil Chavez, of the California Department of Public Health, during a phone call with reporters on Friday.
Chavez delivered his comments as the state health department released a new report summarizing the latest data on this year's pertussis, or whooping cough, epidemic. Of this year's cases thus far, 3,614, or 84%, have occurred in patients 18 or younger. Out of 142 illnesses that required hospitalization, 89, or 63%, were in infants 4 months old or younger.
Three babies in the state have died from pertussis infections in 2014, Chavez said, though two of those will be attributed to 2013's case count because they initially became ill last year.
Because infants less than a year old are at the highest risk of hospitalization and death from pertussis — and because babies generally do not receive pertussis vaccinations until they're 8 weeks old — Chavez said that all pregnant women should receive a dose of the Tdap vaccine during their third trimester.
"Vaccination of pregnant women is the most important thing that can be done to protect infants," he said, because the mothers' antibodies can get passed along to their newborns.
Whooping cough cases peak on a three-to-five-year cycle. Based on historical patterns, Chavez said, it is likely that disease activity will remain high throughout the summer. But he said it was too soon to know if this year would be worse than 2010, the last year pertussis peaked.
That year, more than 9,000 Californians were sickened with the disease.