Clinical case of West Nile fever: difficulties of early diagnosis in neuroinvasive forms

Background. West Nile virus disease ranks as the most leading natural-focal zoonotic diseases in Russia, predominantly in the south of the country, peaking during the summer and autumn months. The first cases of West Nile fever were reported in the Astrakhan region (isolated cases have been observed since 1967, followed by a widespread occurrence since 1997 (8 cases in 1997 and 95 cases in 1999). Subsequently, the disease has spread to the Volgograd (380 cases – since 1999), Rostov (5 cases since 2000), and Ulyanovsk (a single case in 2006) regions. The past 20 years have witnessed a significant expansion of the infection into new regions, with cases reported in the Saratov, Samara, Lipetsk, and Belgorod regions, including some areas of Siberia. In 2010, West Nile fever was first reported in the Chelyabinsk region, the Republics of Kalmykia and Tatarstan, Krasnodar, and Voronezh regions. The same year, outbreaks of West Nile fever were reported in the Volgograd, Rostov, and Voronezh region. Between 2010 and 2024, a total of 2,728 cases of West Nile fever have been recorded in Russia to date. We present a clinical case of a neuroinvasive form of West Nile fever, a combination of encephalitis and acute flaccid paralysis in a 60-year-old man. Most cases of West Nile fever are asymptomatic or mild, and a small proportion of infected people may develop severe neurological forms that can lead to irreversible consequences and death. The mortality rate in the neuroinvasive form of West Nile fever reaches 20%. Difficulties in the diagnosis of neuroinvasive forms in West Nile fever are associated with the non-specificity of the initial symptoms.

Objective. To analyze and describe a clinical case of a patient with a neuroinvasive form caused by West Nile virus. Medical education of doctors on the problem of neuroinvasive forms of West Nile fever.

Materials and methods. The analysis of the inpatient patient's medical history was carried out: clinical symptoms, laboratory parameters, instrumental research data, as well as the dynamics of the patient's condition against the background of therapy.

Results. The clinical picture of the neuroinvasive form of West Nile fever, a combination of encephalitis and acute flaccid paralysis, which caused difficulties in diagnosis and timely administration of drug therapy, is described.

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