Pima County confirms first area West Nile virus death of 2025

A Pima County resident has died from the West Nile virus, Pima County Health Department officials confirmed Wednesday. The unidentified person was the first fatality from the mosquito-borne disease this year, officials said.

Pima County said the person was an older adult with “underlying health conditions,” and was one of two West Nile cases confirmed in Pima County this year. One person showed symptoms last year, while the fatal case was the second during the season — which runs from May through October in Arizona.

Health officials warned they have detected the virus in area mosquitos. Those mosquitos are unrelated to the person who died, indicating a potential risk of West Nile for others.

West Nile virus is typically spread through the bite of an infected mosquito, Pima County officials said. Most people infected don’t show symptoms, but about one in five may develop a “flu-like illness with fever, headache, and body aches.” 

“In rare cases—about one in 150—the virus can cause severe complications like encephalitis or meningitis, which may lead to paralysis, long-term disability, or death,” officials warned. “Older adults, people with underlying health conditions, and those with weakened immune systems are at higher risk for severe illness.” 

People who have symptoms following mosquito exposure should contact a healthcare provider, and PCHD asked physicians and other healthcare providers to consider West Nile when diagnosing patients for similar symptoms.

There have been 1,137 cases of West Nile virus confirmed across the U.S. this year in 42 states, according to the Centers for Disease Control and Prevention. In Arizona, there are 52 confirmed cases—almost all in Maricopa County.

Last year, there were 31 cases in the state, according to the Arizona Department of Health Services.

Despite hot and normally dry temperatures, mosquitoes are
active day and night throughout the year, officials said, adding the “best way to protect
yourself and your family is to take measures to prevent mosquito bites” 

Pima County officials recommended people wear “loose-fitting, light-colored clothing” and use insect repellent on exposed skin. 

Officials also recommended residents keep mosquitos from entering the
home. This includes keeping doors and windows closed, and checking
screens for holes and making repairs.

They added people should work to keep mosquitos out of yards by checking for standing water where mosquitos breed, including outdoor pet water, plant containers, spare tires, or other items that can hold water. This also includes leaky pipes and outside faucets, and said residents should move air-conditioning drain hoses frequently. They also said residents should report mosquito breeding problems, including “green pools.”

People can report “green pools” to Pima County and can get help on how to manage mosquitos in floodplains and ponds by calling mosquito control at 520-724-7908.