Clinical Microbiology and Antimicrobial Chemotherapy. 2008; 10(1):70-84
In the present article the possible causes of discrepancies in the literature data on the efficacy of postexposure prophylaxis of tick-borne encephalitis (TBE) are reviewed. The influence of amount of viral antigen, viral load in the ticks, age of the patients, amount of antibodies in the immunoglobulin preparation and time of its administration on the rate of development of clinical and inapparent infections is analyzed. In total 24934 ticks, removed from the people; 1100 serum samples from 533 tick-bitten persons were included in the study. Efficacy of immunoglobulin preparations with the antibody titer 1:20, 1:80, 1:160 and 1:320 were estimated according to the number of clinically and laboratory proved cases of TBE among non-vaccinated tick-bitten persons. In total the immunoglobulin efficacy were analyzed for 1892 persons (345 children, 1547 - adults). Control group consisted of 51 persons who did not receive immunoglobulin prophylaxis. With the elevation of the tick viral load, the rare of clinical encephalitis significantly increasing. Efficacy of immunoglobulin prophylaxis were significantly (p<0.001) decreasing with the increasing of the viral infectious dose and decreasing of the age of the “bitten person”. Influence of the specific activity of immunoglobulin and time of its use on the development of clinical encephalitis was obvious only in high infectious dose, especially in children. Repeated use of immunoglobulin appear to be not favorable at least in children. Efficacy of immunoglobulin in real practice can significantly vary depending on such factors as infecting dose and characteristics of the microorganism.