Characterization of neutralizing antibodies to Far Eastern of tick-borne encephalitis virus subtype and the antibody avidity for four tick-borne encephalitis vaccines in human.
We assessed the humoral immunity of 290 vaccinated persons against tick-borne encephalitis (TBE). During the first year and 2 years after the primary three vaccinations the antibodies to the Far Eastern subtype tick-borne encephalitis virus strain P-73 were detected by neutralization test after immunization with FSME-Immune Inject vaccine (Baxter Vaccine AG, Austria) in 88.2% and 78.1% vaccinated persons, respectively; with Encepur((R)) Adult vaccine (Novartis Vaccines, Germany), in 100% and 100%; with the vaccine of the Chumakov Institute of Poliomyelitis and Viral Encephalitides RAMSci (Russia), in 100% and 94.1%; with EnceVir vaccine (Russia), in 88.2% and 83.9%; and after combined vaccination, in 100% and 92.7%. The dynamics of the decrease in IgG avidity index correlated with the changes of antibody titers determined by neutralization test. After the primary vaccination course, the titers of virus-neutralizing antibodies were high (6.3-7.4 log(2)) when the avidity index of IgG antibodies were 31% and more; thus, this level can be considered immunologically significant. Two years after the primary vaccination course, the IgG avidity indexes of 60% and more can be regarded as significant on the background of the GMT decrease of virus-neutralizing antibodies. These results allow us to recommend all four vaccines for mass vaccination and an assay of IgG avidity, along with neutralization test, for a more adequate assessment of the level of postvaccination immune response.
Research Institute of Epidemiology and Microbiology, Siberian Branch of Russian Academy of Medical Sciences, Vladivostok, 690087, ul. Selskaya 1, Russia. galinaleon@mail.primorye.ru
Galina N
GN
Leonova
Elena V
EV
Pavlenko
D000914:Antibodies, Viral / Q000097:blood / Q000276:immunology*; D000915:Antibody Affinity / Q000276:immunology*; D004669:Encephalitis Viruses, Tick-Borne / Q000276:immunology*; D004675:Encephalitis, Tick-Borne / Q000276:immunology*; D005202:Asia, Eastern; D006801:Humans; D007118:Immunoassay; D009500:Neutralization Tests; D017186:Titrimetry; D014765:Viral Vaccines / Q000276:immunology*
D000914:Antibodies, Viral; D014765:Viral Vaccines