[Demonstration of the tick-borne encephalitis virus by an immunoenzyme method during a study of its persistence and the chronicity of the process in experimental animals]. / Indikatsiia virusa kleshchevogo éntsefalita immunofermentnym metodom v khode izucheniia persistentsii i khronizatsii protsessa u éksperimental'nykh zhivotnykh.

The studies carried out by the authors indicated the advantages of the enzyme-immunoassay (EIA) for the detection of the persisting tick-borne encephalitis (TBE) virus and in verification of the chronic course of TBE as compared with HA test, HI test and biologic neutralization test. This method detected TBE virus in the brain of most animals developing the disease within 30-300 days postinoculation. In mice developing no disease the persisting virus was detected both directly in the organs and after preliminary amplification in a sensitive biological model and by the tissue explant method. The EIA was particularly effective in the study of persistence at later intervals (100-300 days), when the hemagglutinating and infective activities of the virus declined. The method is more informative, specific and less labor-consuming.

[Immune complex formation during the passive immunization of mice infected with the tick-borne encephalitis virus]. / Obrazovanie immunnykh kompleksov pri passivnoi immunizatsii myshei, zarazhennykh virusom kleshchevogo éntsefalita.

The results of investigations, indicating that the development of the infectious process in experimental encephalitis is accompanied by the formation of immune complexes circulating in the blood and localized in the brain tissue, are presented. The intravenous injections of a homologous serum preparation into intact animals induces the appearance of a rather low level of circulating immune complexes, which precedes the elimination of antibodies. The intravenous injection of a specific serum preparation two days after the infection of the animals with tick-borne encephalitis virus is accompanied by the formation of immune complexes; the course of infection is not aggravated.

[Results of using the ELISA method in studying tick-borne encephalitis and rabies]. / Rezul'taty ispol'zovaniia metoda ELISA pri izuchenii kleshchevogo éntsefalita i beshenstva.

The results of using the indirect variant of ELISA for the study of serum samples from humans and white mice for the presence of antibodies to tick-borne encephalitis virus and rabies virus are presented. The high sensitivity and specificity of this method have been confirmed.

[Possible use of a concentrated vaccine against tick-borne encephalitis for immunizing donors to obtain specific immunoglobulin]. / O vozmozhnosti primeneniia kontsentrirovannoi vaktsiny protiv kleshchevogo éntsefalita dlia immunizatsii donorov s tsel'iu polucheniia spetsificheskogo immunoglobulina.

The immunization of donors with dried, purified, inactivated and concentrated cell-culture tick-borne encephalitis vaccine, produced at the Institute of Poliomyelitis and Viral Encephalitides in Moscow, has been carried out with the aim of obtaining immune raw material for the production of specific donor immunoglobulin. The high immunogenic potency and low reactogenicity of the vaccine, introduced in 2 injections at an interval of 6 months, have been confirmed. Immunization in 2 injections has proved to be as effective as that achieved by 3 injections. The expediency of the immunization of regularly bled donors has been established: hemagglutinin titers in these donors have been found to be significantly higher than in a group of persons never bled before. The optimum time for taking blood has been determined: 3 weeks for regularly bled donors and 2 weeks for donors bled for the first time. Blood may be taken again 2 months after the first bleeding without booster immunization and 2 weeks after the third injection of the vaccine.