Average annual coccidioidomycosis incidence rate* by age (N = 2234), Los Angeles County, California, 1995–2011.

<p>Legend. *Average annual incidence rates were calculated by dividing the average annual number of cases for 1995–2003 and 2004–2011 by the U.S. Census population counts for 2000 and 2010, respectively. The period of 1992–1994 was excluded because these were outbreak years. For all age groups, average annual incidence rates increased substantially between 1995–2003 and 2004–2011. The percent increase ranged from 151% to 318%, with age groups ≥65, 0–14, and 15–24 years having the greatest increases. During 1995–2003, incidence rates increased with age until age group 55–64 years. However, during 2004–2011, incidence rates continued to increase in the age group ≥65 years.