Federal health agency says flu season in California worst since 2009

With 405 reports of severe influenza cases -- deaths, or hospitalizations requiring intensive care -- 2013-2014 is shaping up to be the most severe since 2009’s swine flu pandemic, according to a new report from the U.S. Centers for Disease Control and Prevention.

Writing as part of a package of flu-related studies in the agency’s Morbidity and Mortality Weekly Report on Thursday, researchers from the CDC and the California Department of Public Health offered new details about the impact of this year’s flu on people under the age of 65.

Looking at the period between Sept. 29 and Jan. 18, the team found that local health authorities in California reported 94 deaths and 311 ICU admissions for people with influenza. More than a quarter of these severe cases -- 103 -- started suffering flu symptoms during the week ending Jan. 11.

The team didn’t have complete information for every patient, but available data supported several things health authorities had already surmised about this season’s flu. All of the deaths and almost all of the illnesses were caused by infection with the H1N1 swine flu strain. It’s striking adults particularly hard: of the 405 severe cases, 266, or two-thirds, were in people between the ages of 41 and 64. Only 39 cases were in children under the age of 18, including three deaths.

Among all the patients who died, researchers had vaccination histories for 28 people: only six had gotten immunized. The team had information about underlying conditions in 80 of the patients who died. Of these, 74 suffered from conditions -- such as diabetes, obesity or lung problems -- that put them at high risk of getting flu complications.

The CDC report did not include flu deaths or cases reported by healthcare authorities after Jan. 18. As of Friday, California had confirmed 243 deaths for the season, and reported that 41 more confirmations were likely. Los Angeles County, which counts flu casualties differently, reported 52 deaths on the same day.

Among those deaths was that of a pregnant South Bay woman and her fetus.

“This sad event demonstrates that serious complications can occur with flu infection in pregnant women,” said Jonathan E. Fielding, the county’s director of public health and health officer. “It is critical that all pregnant and postpartum women get vaccinated to protect themselves against the flu.”

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