Analysis of immunological efficacy of influenza virus vaccine during years of 2002～2004 in Lanzhou

In order to observe the immunological efficacy of influenza virus vaccine in between September and November from 2002 to 2004 in Lanzhou,Gansu Province of China,44,52 and 49 healthy persons inoculated the vaccine were evaluated in each period of time respectively.The serum samples were collected before and after vaccination,antibodies were determined by HI(haemagglutination inhibition) test.The result showed that HI antibodies related to four serotypes of influenza virus were increased with different levels during 30～35 days after vaccination.The ratios for protection(≥1∶40) of four subtype virus(H1N1、 H3N2、B2(Victoria),B1(Yamagata)) were 91.72%,91.72%,71.03%,and 59.38%;GMT were 1∶221.76,1∶189.58,1∶71.04,and 1∶43.04;the increasement more than 4 folds for HI antibodies titers were 53.79%(78/145),58.62%(84/145),58.37%(56/96)and 75.51%(37/49) after vaccination respectively.It shows that this vaccine has an excellent immunization efficacy and exerts success in protection.