Locally Acquired Dengue Infections Reported in Arizona

A new report in Morbidity and Mortality Weekly Report (MMWR) explores how health and environmental agencies in Maricopa County, Arizona, responded to an outbreak of locally acquired dengue virus (DENV) in November 2022. The outbreak consisted of two DENV infections and ended Jan. 4, 2023, after 45 days without additional locally acquired cases.

Dengue is caused by a group of four related viruses spread by Aedes species (Ae. aegypti or Ae. albopictus) mosquito. In the United States, most DENV cases result from travel to endemic areas, but locally transmitted outbreaks have occurred in Florida (2020), Hawaii (2015) and Texas (2013).

In the report, the authors describe the actions of the Maricopa County Environmental Services Department and Maricopa County Department of Public Health to confirm and control the outbreak. This included canvassing and interviewing residents who lived near patients with confirmed DENV cases, launching a health care provider education program and conducting environmental assessments to locate mosquito breeding sites.

Additional information about DENV is available on AABB’s dengue viruses fact sheet.