Severe tick-borne encephalitis in Slovenia in the years 2001-2005: time for a mass vaccination campaign?

• Published in: Wiener Klinische Wochenschrift 2006-12, Vol.118 (23-24), p.765-768
• Main Authors: Jereb, Matjaz, Karner, Primoz, Muzlovic, Igor, Jurca, Tomaz
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Antibodies, Viral - blood; Cross-Sectional Studies; Encephalitis Viruses, Tick-Borne - immunology; Encephalitis, Tick-Borne - epidemiology; Encephalitis, Tick-Borne - immunology; Encephalitis, Tick-Borne - prevention & control; Female; Humans; Immunoglobulin G - blood; Male; Mass Vaccination; Middle Aged; Retrospective Studies; Risk Factors; Slovenia; Viral Vaccines - administration & dosage; Viral Vaccines - immunology
• ISSN: 0043-5325; 1613-7671
• DOI: 10.1007/s00508-006-0728-5

The aim of this retrospective study was to assess some clinical, epidemiological and laboratory parameters of severe tick-borne encephalitis in Slovenia in the last five years, to compare them with published data, and to estimate need for providing a policy of active immunization. Thirty-three adult patients with a severe course of the disease, admitted to the intensive care unit of the Department of Infectious Diseases, University Medical Centre Ljubljana, Slovenia during a five year period, participated. All the patients had specific serum IgM antibodies against tick-borne encephalitis virus at admissions and IgG antibodies were present in 29 out of 33 patients. Twenty-two patients were admitted because of severe consciousness disturbances, nine suffered from spinal nerve paralysis, in two patients cranial nerve paralysis was observed, and one suffered from generalized tonic-clonic seizures. Ten patients were mechanically ventilated and three died. Leukocytosis in peripheral veins was found in twenty-one patients and nine had a C-reactive protein serum concentration over 50 mg/l. Nineteen patients had a cerebrospinal fluid leukocyte count exceeding 100 x 10(6)/l and a cerebrospinal fluid protein concentration was over the cut-off value of 0.45 g/l in majority. The findings of the present study confirmed some previous reports about clinical, epidemiological and laboratory characteristics of patients with severe tick-borne encephalitis. We have found that tick-borne encephalitis in Slovenia has a relatively low fatality rate. However, the severe course with long-lasting sequelae of the disease justifies vaccination of a risk population in endemic areas.