Mosquito & Vector-Borne Diseases

Even here in the dry climate of Maricopa County, mosquitoes are a problem. Mosquitoes are small insects that breed in standing water and the female mosquitoes need blood to lay eggs. Sometimes mosquitoes carry germs (e.g., viruses and parasites) that can be spread to a person when the mosquito bites them. Preventing mosquitoes from breeding and avoiding mosquito bites are the best ways to avoid getting these diseases.

To learn more about each mosquito-borne disease, find its name below. 
Mosquito

Mosquito-Borne Diseases in Maricopa County 2020

Confirmed and Probable Cases & Deaths as of 4/2/2020

Locally Acquired

DiseaseCurrent Year CasesCurrent Year DeathsCases Same Date Last YearDeaths Same Date Last Year2019 Total Number of Cases
St. Louis Encephalitis (SLE)00007
West Nile Virus (WNV)1010155
Unspecified Flavivirus (SLE/WNV)00
001

Travel-Related*

DiseaseCurrent Year CasesCurrent Year DeathsCases Same Date Last YearDeaths Same Date Last Year2019 Total Number of Cases
Chikungunya
10
001
Dengue30
0013
Zika00
000
Unspecified Flavivirus (Dengue/Zika)00
0
00

All data are provisional, based on date reported to Public Health.

Current Year = 2020
Last Year = 2019

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 indicates an infection that could not be attributed to a single mosquito-borne disease.

Find annual summary numbers of mosquito-borne diseases in Maricopa County, including the number of human deaths attributed to them .

Additional mosquito-borne disease data may be found on the Arizona Department of Health Services’ Mosquito-Borne Disease webpage.

DISEASES