Study on immunological effect and adverse reaction of influenza A (H1N1) vaccine and seasonal influenza vaccine in a military unit

Objective To understand the antibody levels and adverse reaction (ADR) of healthy people before and after vaccinating pandemic influenza A H1N1 (pH1N1) vaccine and seasonal influenza vaccine(SIV),and then evaluate the immunogenicity and safety of pH1N1 vaccine and SIV.Methods A total of 760 subjects who met the requirements were randomly individed into 2 groups:the pH1N1 vaccine recipients group (VH group,n =460) and the SIV recipients group (VS group,n =300).The ADR after immunization of 2 groups were recorded and analyzed respectively.The sera antibody levels were separately detected before and after immunization with two vaccines by the hemagglutinafion inhibition (HI) test.Results The total ADR rate of 760 cases was 7.50％(57 cases),including 29 cases (6.30％) in VH group and 28 cases (9.33％) in VS group.ADR rate had no significant difference between 2 groups (x2 =2.40,P＞0.05).No serious ADR was observed.Twenty one days after vaccination,anti-pH1N1-positive seroconversion rate was 95.65％,GMRT was estimated as 1∶424.4(95％ CI:325.07-523.76) in VH group; in VS group,the GMRT of anti-seasonal influenza virus increased to 1 ∶ 183.8(95％ CI:71.32-296.28).Conclusions The pH1N1 vaccine shows good safety and immunogenicity.It is suit for the crowd without contraindications of vaccination universally. Key words: Influenza A virus, H1N1 subtype;  Vaccines;  Adverse reaction;  Micro-hemagglutination-inhibition; Antibody positive seroconversion rate