Three Davis County residents died from West Nile virus in 2025, according to the Davis County Health Department's annual communicable disease report.

The county recorded seven West Nile cases last year, the highest total since 2021. Of four West Nile deaths reported statewide in Utah, three were Davis County residents, the report said.

The report, prepared by the Division of Communicable Disease and Epidemiology (CD/Epi) under Director Sarah Willardson, also documented the county's first confirmed measles cases in at least 25 years.

West Nile spike

West Nile virus, or WNV, infection rates in Davis County have climbed steadily since 2022, the report said. The seven cases in 2025 represented a sharp jump from three cases in 2024 and two in 2023.

Most infections go undetected. The report noted that up to 80% of WNV infections cause mild symptoms or none at all. Less than 1% of infected people develop severe neurological disease such as meningitis or encephalitis. Older residents and those with weakened immune systems face higher risk.

The health department described a "somewhat cyclical pattern" of West Nile activity over the past 11 years and said that if past trends hold, the elevated numbers could decrease in coming years.

The report did not identify which cities within Davis County recorded the cases or deaths.

Measles returns after 25-year gap

Davis County confirmed three measles cases in November 2025, tied to the nationwide outbreak that began in Texas in January of that year. Utah's first case appeared in June 2025. The county had not recorded a confirmed measles case in at least 25 years.

Health investigators tracked 76 contacts linked to the three cases and identified four public locations where exposure may have occurred. Another 42 county residents with measles-like symptoms tested negative.

CD/Epi provided post-exposure treatment to 11 people, including two who received measles immune globulin. The majority of Utah's outbreak cases occurred in southwestern Utah, and Davis County's measles rate remained below the state average, the report said.

Other findings

The report documented five disease outbreaks at long-term care facilities in 2025, affecting 118 people total. One involved invasive Group A Streptococcus at a medical care facility. Investigators traced the likely source to contract clinical providers who worked at multiple facilities along the Wasatch Front.

Three rabies-positive bats were found in Davis County in 2025, a typical annual count for the county. The department investigated 140 animal bite cases and recommended rabies post-exposure treatment for 114 of them.

Residents with questions can contact the Davis County Health Department at (801) 525-5200 or [email protected].