GPT and Decreased total leukocyte count: In conclusion, febrile illness caused by TBEV infection is characterized clinically by the presence of malaise or fatigue (98%), fever (97%), headache (86%), and myalgias (54%) and in laboratory tests by leukopenia (88%), thrombocytopenia (59%), and abnormal liver results (63% of patients had >1 abnormal liver test, usually elevated AST and ALT) but normal inflammatory markers.