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.
Leonova
Galina N
GN
Research Institute of Epidemiology and Microbiology, Siberian Branch of Russian Academy of Medical Sciences, Vladivostok, 690087, ul. Selskaya 1, Russia. galinaleon@mail.primorye.ru
Pavlenko
Elena V
EV
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