On Oct. 30, 2023, the California Department of Public Health (CDPH) reported the first locally acquired case of dengue in California was detected in a Pasadena resident; no other locally acquired dengue cases were identified in California.

The potential risk for acquiring dengue virus in Los Angeles County and California was low. The resident did not travel outside the county before illness onset.

From 2018 to 2022, CDPH has documented an average of 124 travel-associated cases of dengue per year among California residents. This is the first documented case of locally acquired dengue in California. Sporadic clusters and locally acquired cases of dengue have occurred in other states including in Arizona, Florida, Hawaii, and Texas. The size of clusters in these states has been relatively small and limited