The California Department of Public Health (CDPHi) Influenza
Surveillance Program is a collaborative effort between CDPH, the
CDC, Kaiser Permanente, California local health jurisdictions and
participating sentinel providers and laboratories.
Annual influenza epidemics follow a winter seasonal pattern in
the United States with typical activity peaking during late
December to early February. CDPH obtains and analyzes clinical,
pharmacy and laboratory data year-round in an effort to determine
the timing and impact of influenza activity and to determine how
well circulating strains of the virus match those used in the
current influenza vaccines.
The most current weekly report on influenza and other respiratory
disease activity can be found below, under “Hot Topics &