Oxford, September 22, 2025 – Growing numbers of West Nile virus infection cases, fueled by climate change, are sparking fears among citizens and healthcare providers in Europe. A Clinical Insight in the European Journal of Internal Medicine , published by Elsevier, aims to raise awareness and equip medical professionals with the knowledge needed to recognize and manage this emerging disease to avoid further spread and serious health consequences, especially for vulnerable individuals.
"Climate change is affecting our health by allowing disease-carrying insects to spread into new areas. We are now seeing a growing number of illnesses like West Nile virus infection in places they were not found before, including in Europe. Since the number of West Nile virus cases is on the rise, it is now more important than ever to increase our knowledge to recognize, diagnose, and treat this emerging disease," says lead author Emanuele Durante-Mangoni, MD, PhD, University of Campania 'L. Vanvitelli,' and AORN Ospedali dei Colli, Naples, Italy.
The West Nile virus is a mosquito-borne virus that can attack the nervous system and brain. It was first identified in 1937 west of the Nile River in what is now Uganda. It is a highly variable virus for which no human vaccine is currently available. However, identification of the disease can facilitate identifying areas of spread where dedicated interventions, largely mosquito eradication, can be performed in an attempt to avoid further spread and related morbidity.
Dr. Durante-Mangoni explains, "The insect gets infected after biting birds that carry the virus. Seasonality is also linked to bird migration patterns, another natural phenomenon affected by climate change. After West Nile virus infection, most humans show no symptoms (80%) or develop mild symptoms of a viral illness, typically characterized by the abrupt onset of fever. It is also associated with headache, malaise, anorexia, myalgia, eye pain, diarrhea, and vomiting. In some at-risk individuals, such as the elderly, those who are frail, or have other health issues, the disease can progress to a more serious form, often involving the brain, and can possibly have severe or even fatal consequences."
The authors' goal is to help prepare the scientific community to deal with the expected increase in the incidence of West Nile virus cases by outlining the virology, clinical presentation, diagnostic approach, and the current suggested management of this emerging disease. They advise that efforts should concentrate on:
- Working towards developing a vaccine for human use that can protect those at higher risk of complications and/or progression.
- Trying to identify an antiviral agent that can block the virus at an early stage, before neurological involvement occurs.
"Clinicians need to become skilled enough to identify the illness and make a rapid and accurate diagnosis and also be aware of endemic/epidemic areas of West Nile virus diffusion, to speed up the diagnostic path in frail and immunocompromised patients who remain at risk for an ominous outcome," emphasizes Dr. Durante-Mangoni. "The ultimate strategy would be vaccination of subjects at risk. Despite efforts, as yet no vaccine has reached an advanced stage of clinical development, but there is hope for the future."
