FOLLOW-UP STUDIES OF TICK-BORNE ENCEPHALITIS (ECOLOGICAL, EPIDEMIOLOGICAL AND EXPERIMENTAL LABORATORY STUDIES.
Final technical rept. Apr 67-Mar 68,
VIENNA UNIV (AUSTRIA) HYGIENE INST
Pagination or Media Count:
TBE virus was isolated from ticks collected in Upper Austria, Lower Austria and Northern Moravia. From 278 sera of small mammals 12 had antibodies. The role of shrews in the virus cycle cannot be greater than that of mice. Game has a high incidence of antibodies. Roe deer is the best indicator for the virus in nature. Hemagglutination inhibition studies with phospholipids substantiated that polyphosphoinositides act as receptor for TBE virus. A plaque method was elaborated for the assay of West Nile virus used as a model for TBE virus. Lipids inhibit the adsorption of the virus onto chick cells regardless of the pH. Studies were commenced to obtain protective antibodies against receptors of TBE virus. After experimental infection, roe calf and foxes developed neutralizing antibodies but not viremia. In nymphs infected as larvae on viremic Apodemus flavicollis virus reappeared after a long eclipse. An unusually low incidence of TBE was recorded in Austria. Hyperimmunoglobulin 0.1 mlkg given in phase 1 of TBE failed to protect against overt disease. The agent of hemorrhagic fever in Germany is not related to the hemorrhagic fever viruses of the TBE complex, yet it resembles in some ways arboviruses. Author