Vector-Borne & Zoonotic Reports

The Maricopa County Department of Public Health (MCDPH), Office of Epidemiology, and the Maricopa County Department of Environmental Services (MCESD), Office of Vector Control, collaborate to educate and protect the residents of Maricopa County against mosquito-borne illness.

Mosquito-Borne Diseases in Maricopa County 2022

Confirmed and Probable Cases & Deaths as of 05/12/2022

Locally Acquired

*The number of WNV cases currently under review and pending classification is 5. This number is not reflected in the number of current cases above.
^‡ Seven cases were reported in 2022 but occurred or had incubation periods in 2021

Travel-Related**

All data are provisional, based on date reported to Public Health.
Maricopa County weekly counts may vary slightly from state reporting due to differences in data reporting.

Current Year = 2022
Last Year = 2021

Disease Statistic Notes 

^{** Travel-related cases are those in which residents brought the disease in from other places or passed on the disease during birth as the result of infection acquired during travel.
† Unspecified Flavivirus Opens a New Window.  indicates an infection that could not be attributed to a single mosquito-borne disease.}

West Nile Virus End of Year Reports
The WNV end of year report provides information such as the annual number of WNV cases in Maricopa County, WNV activity by month, WNV rates per city, and number of mosquito pools by month.

• Latest End of Year Final Report (PDF)
• View All the End of Year Final Reports

Other Mosquito-Related Diseases
Other county reports for mosquito-borne illness are generated on an as needed basis.  

• West Nile and St. Louis Encephalitis Virus End of Year Report (2017)
• St. Louis Encephalitis Virus End of Year Report (2015)

Mosquito-Borne Disease End of Year Reports
The end of year report provides information related to all local and travel-acquired mosquito-borne illness cases in Maricopa County. Data includes types/frequency of symptoms, locations of disease transmission, and characteristics of human infections. 
End of Year Final Report (PDF) 

Mosquito Sampling Statistics
Maricopa County Environmental Services Department (MCDES) Vector Control has an extensive mosquito trapping and testing program that enables staff to identify areas where there is a lot of mosquito activity and to detect mosquito-borne diseases. View the Mosquito-Borne Disease Statistics page for details.

 For more data not found here, you also can visit the ADHS Mosquito-Borne Illness page.