Ogilvy et al.
Meningoencephalitis caused by tick-borne encephalitis virus in a returning traveler, United States, 2023. AIM Clin Cases. 2025;4:e241242. doi:10.7326/aimcc.2024.1242
A case of tick-borne encephalitis (TBE) has been reported in a traveler returning to the United States. The individual had spent time in Moscow—where TBE virus has been detected in city parks (see Snapshot Week 33/2029)—and visited friends and relatives in Western Siberia, where he engaged in outdoor activities including forest hiking.
The patient experienced malaise and fatigue during the return flight. After a three-day asymptomatic period, he developed fever, headache, neck pain, and subsequently aphasia and meningoencephalitis. TBE was suspected and later confirmed through a plaque reduction neutralization test. Fifteen months after the initial illness, the patient continued to report fatigue and difficulties with attention.
In the United States, TBE is likely underdiagnosed due to limited clinical awareness and the absence of widely available commercial testing. The authors highlight that the Advisory Committee on Immunization Practices recommends TBE vaccination for travelers visiting endemic areas who are likely to engage in activities with a high risk of tick exposure.