North Carolina health officials confirmed two West Nile virus deaths among adults in the central part of the state, where CDC data show 11 human cases this season.
Two adults from central North Carolina have died after contracting West Nile virus, according to the North Carolina Department of Health and Human Services (NCDHHS).¹ The department has not disclosed the counties where the patients lived.¹ The deaths come as CDC data show 11 reported human West Nile virus cases in North Carolina as of October 6, 2026.¹
NCDHHS noted older adults and people with underlying health conditions face the greatest risk for severe illness and death.¹ The mosquitoes most often responsible for transmission are found statewide and are most active between dusk and dawn, according to the department.¹ Most US cases begin between July and September, but about 6% of 2023 cases had onset in October through December.⁴
West Nile virus remains the leading cause of mosquito-borne disease in the contiguous United States.³ The virus causes an average of 2,000 reported disease cases each year, including about 1,200 neuroinvasive cases and roughly 120 deaths, according to CDC investigators.⁴ In 2023, health departments in 46 states and the District of Columbia reported 2,628 cases, 1,891 hospitalizations, and 194 deaths.⁴
Reported totals substantially understate the true burden of infection. CDC investigators estimate 30 to 70 nonneuroinvasive cases occur for every reported neuroinvasive case.⁴ Based on 2023 data, between 53,670 and 125,230 nonneuroinvasive cases likely occurred, but only 839 were reported.⁴
The North Carolina Department of Health and Human Services reported the deaths of two adults from central North Carolina but has not released where they lived.
West Nile virus causes an average of 2,000 reported US disease cases and roughly 120 deaths each year, according to the CDC.
No antiviral therapy or human vaccine exists, and about 10% of patients with neuroinvasive disease die.
Wild birds carry West Nile virus, and mosquitoes transmit it to people after feeding on infected birds; the virus does not spread from person to person.¹ Rare transmission also occurs through blood transfusion and organ transplantation.⁴ The incubation period typically runs 2 to 6 days but can extend to 14 days, and longer in immunocompromised patients.²
About 80% of infections are asymptomatic, and most symptomatic patients develop a febrile illness with headache, myalgia, arthralgia, rash, or gastrointestinal symptoms.² Fewer than 1% of infected people develop neuroinvasive disease, presenting as meningitis, encephalitis, or acute flaccid myelitis.² Neuroinvasive disease develops in about 2% of infected people aged 65 years or older, compared with less than 0.5% of younger people.²
Among patients with neuroinvasive disease, the overall case fatality rate is approximately 10%.² Mortality reaches about 20% in patients aged 70 years or older, compared with about 2% in people younger than 50 years.² Mortality climbs to 30% to 40% among patients with hematologic malignancies, transplant recipients, and patients receiving anti-CD20 monoclonal antibody therapy.²
Survivors often face lasting effects. Between 30% and 40% of hospitalized patients are discharged to long-term care or rehabilitation facilities, and more than half report ongoing symptoms beyond 1 year.² Cancer, diabetes, hypertension, renal disease, and immunosuppression also raise the risk of neuroinvasive disease.²
No medication is approved to treat West Nile virus disease, and clinical management is supportive.³ Several agents have been evaluated or used empirically, but none has shown conclusive benefit.³ Patients with encephalitis require close monitoring for elevated intracranial pressure, seizures, and airway compromise, and patients with acute flaccid myelitis require monitoring for rapid neuromuscular respiratory failure.³
No vaccine is licensed for human use, so prevention depends on community mosquito control, personal protective measures, and screening of blood and organ donors.³ Patients with confirmed infection should not donate blood for 120 days after illness.³ CDC investigators advise clinicians to consider arboviral testing in patients with acute febrile or neurologic illness during mosquito season, and to order West Nile virus testing specifically, since commercial arboviral panels often omit it.⁴
