Bogdanic et al.
The re-emergence of neuroinvasive flaviviruses in Croatia during the 2022 transmission season. Microorganisms. 2024; 12(11):2210. https://doi.org/10.3390/microorganisms12112210
Various flaviviruses are known to circulate in Croatia, including the tick-borne encephalitis (TBE) virus. Most TBE cases have been reported from the northwestern counties of Croatia.
Between April and November 2022, 110 hospitalized patients with suspected neuroinvasive arboviral infections were tested for TBE virus, West Nile virus (WNV), and Usutu virus infections. TBE virus infections were confirmed in 24 patients aged 15–72 years, 22 of which were autochthonously acquired. The majority of patients were at least 61 years old, with most infections detected in May and June. The primary clinical presentation among Croatian patients was meningitis, observed in 63.6% of cases.
A cluster of 13 TBE virus infections was identified in Gorski Kotar, a mountainous region situated between continental and coastal Croatia, also known as “Croatian Switzerland.” This area borders Slovenia, a country with a high incidence of TBE virus infections.
Additionally, WNV infections were detected in both humans and horses, while Usutu virus infections were identified in horses and mosquitoes.