Study on tendency of antibodies levels of influenza A(H1N1) vaccine inoculated population in Jiangsu Province

Objective To investigate the developing tendency of antibodies levels of the type A(H1N1) influenza vaccine inoculated people.Methods Observation objects were randomly selected from people vaccinated with influenza A(H1N1) vaccine,and their antibody titers were tested with Hemagglutination inhibition(HI) assays before immunization,1 month and 3 month after it respectively.Antibody positive rates of influenza A(H1N1) virus and their Geometric mean titer(GMT) of HI antibody were estimated.Results The seropositive rates at these 3 time spots(before the vaccination,1 month and 3 month after it) were 13.64%(9.58%~18.61%),83.63%(78.15%~88.20%),77.06%(71.09%~82.32%) and GMT were 9.36(8.30~10.56),122.53(100.29~149.70),96.07(77.85~118.54) respectively.The antibody positive rates' level and GMT were significantly higher than that of preimmunization,while differences between 1 and 3 month post-immunization antibody levels and GMT had no statistical significance.Conclusions The influenza A(H1N1) split-virion vaccine used in the present study could induce a high and persistent antibody level.