[Reactivity and immunologic activity of polyvalent split influenza vaccine in children].

In a group of 144 children (six months to 15 years) three doses vaccine were administered. The latter contains the main strains of the influenza type A and strain type B. From the clinical evaluation ensued that this vaccine in children is areactogenic even after repeated doses. The morbidity was followed up for 18 months and during this period in the immunized communities no case of influenza was recorded. The antibody levels were assessed by the haemagglutination-inhibition test (HIT) and the enzyme test (NIT) The assessed HI titres were high after the second and third dose, in particular as regard subtype H3N2 and H1N1. The titres against subtype H2N2 and type B were markedly lower. Antibodies against neuraminidase were highest against subtype N1 and type B, lowest against N2. The dynamics of the formation of antineuraminidase antibodies was similar as that of haemagglutination-inhibition antibodies. Based on these results the vaccine is evaluated as very satisfactory and after approval by the Ministry of Health and Social Affairs this vaccine will be used for a field trial in 1-2 thousand children where above all the protective effect of the vaccine will be investigated. This vaccine is intended for children, with the aim to induce complex immunity against influenza.