Tick-borne encephalitis: literature review

Justina Jermolajevaitė1, Danielė Jukonienė1, Laura Saudargaitė1

1Lithuanian University of Health Sciences, Medical Academy, Faculty of Medicine


Tick-borne encephalitis (TBE) is a human viral infectious disease, which is caused by tick-borne encephalitis virus (TBEV) and transmitted by ticks. TBE is widespread among Middle, North and Eastern European countries, although the ticks, which transmit the disease can be found from Western Europe to Japan. In Eastern Europe the main TBE transmitter is Ixodes ricinus tick. The mortality rate at the moment ranges from 0,5 – 4%. TBE course of the disease can be monophasic or biphasic, but in Europe the widespread type is biphasic. The first phase is followed by fever, headache, muscle pain, nausea and the second phase is characterized by fever and signs and symptoms of CNS inflammation. According to which anatomical CNS site is affected there are three main clinical TBE forms: meningitis, encephalitis or meningoencephalomyelitis. The most common form of TBE is meningitis. The diagnostic of TBE is based on clinical and laboratory findings. TBE is confirmed when there are clinical symptoms of meningitis, encephalitis or meningoencephalomyelitis with cerebrospinal fluid (CSF) pleocytosis (>5×106 cells/l) and the presence of specific TBEV serum immunoglobulin M (IgM) and IgG antibodies, CSF IgM antibodies or TBEV IgG seroconversion. PCR method to detect TBEV can be used only during the first phase when the virus can be found in the blood. MRI of the brain and spinal cord has low sensitivity and low specificity, so it shouldn’t be used routinely, except the cases to differentiate cerebral oedema. The treatment is symptomatic and includes antipyretics, non-narcotic analgesics, antiemetics, CNS depressants and if needed – anticonvulsants for seizures. If cerebral edema occurs – osmotherapy with mannitol should be administered. The person who underwent TBEV gets lifelong immunity for this disease. Vaccination against TBE is the most effective mean to prevent this disease its efficacy according to research is 95-97%. Vaccination is recommended for all age groups above 1 year in highly endemic areas.

Keywords: ticks, tick-borne encephalitis, tick-borne encephalitis vaccine.