Background Most TBE virus infections remain asymptomatic; but when the infection is symptomatic, the disease can manifest with fever and can often involve the central nervous system (CNS) which leads to tick-borne encephalitis. When an individual is infected by a European subtype of TBE virus, the illness mostly results in a biphasic course. After an initial phase which usually lasts not longer than a week and which corresponds to viremia, typical symptoms are fever, fatigue, malaise and headache, the illness improves for a few days, and then the second phase starts with CNS involvement. However, TBE virus infection can also result in an isolated initial phase of TBE, the abortive form of TBE, also called summer flu, and without involvement of the CNS. A TBE virus infection without CNS involvement is believed to be favorable. A Slovenian team of experts has analyzed in detail the clinical and laboratory characteristics of febrile illness in patients in whom TBE virus infection was established by the presence of viral RNA in the blood.
By Michael Bröker Editor, TBE News
