TICK-BORNE ENCEPHALITIS (TBE) IN CHILDREN FROM 1980 THROUGH 1999 IN STYRIA/AUSTRIA

W. Zenz, H. Pansi, I. Mutz, M. Cizman, A. Kraigher, A. Berghold, D. Spork

Dept. of Pediatrics., University of Graz, Austria., Dept. of Infectious Diseases, University Medical Center, Ljubljana, Slovenia., Institute for public health of the republic of Slovenia, Slovenia., Institute of Medical Informatics, Statistics and Documentation, University of Graz., Dept. of Pediatrics, Univ. of Graz

Background: The state of Styria has a population of 1,1 million and is a high risk area for TBE, which until 1980 was the most common cause of acute meningoencephalitis in children. In 1981 a vaccination program against TBE for persons older than 6 years was started and extended in 1984 to all children beyond one year of age.

Methods: To determine the incidence of TBE and of long term neurological sequelae in children from 1980 through 1999, to correlate the incidence of TBE to the vaccination rate against TBE, and to compare these data with data from the neighbouring Slovenia.

Results: From January 1980 to December1999 136 cases of TBE in children younger than 16 years were observed in Styria: 1980-1986 6 - 26 /year, 1987-1992 1-5 /year, 1993-1999 0 to 2 /year. 6/136 (4 %) children with TBE developed long term neurological sequelae (hearing loss or epilepsy). The incidence of TBE 1993-1999 was 6,8 - 27,4 /100.000 children/year in Slovenia (vaccination rate in children below 1%) versus 0 - 0,9 /100.000 children/year in Styria (vaccination rate in children over 95%).

Conclusions: These data show that within a distinct area a program of active vaccination against TBE for all children beyond one year of age has - within a six-year-period - resulted in an almost complete disappearance of TBE in this age group while without vaccination the incidence in the neighbouring region remained constant.