RESUMO
The specific features of the etiology of influenza in children and adults at the period of the simultaneous circulation of two subtypes of influenza virus A, according to the results in the hemagglutination-inhibition reaction in 261,490 influenza and ARD patients hospitalized in St. Petersburg in the course of 32 years, were analyzed. The results of serological diagnostics was shown to correspond to the data of the identification of influenza viruses in Russia and all over the world. At the period of epidemics diseases caused by the main infective agents of the epidemics were detected in 11.0% - 51.0% of cases and by concomitant infective agents, in 0.6% - 12.4% of cases. After the reappearance of influenza virus A(H1N1) in circulation higher frequency of mixed forms of infection and the presence of competition between the subtypes of influenza virus A was noted. In young children a decrease in differences in the proportion of influenza cases, caused by the main and concomitant infective agents, as well as between the detection of influenza in epidemic and in summer periods, was registered.
Assuntos
Anticorpos Antivirais/sangue , Vírus da Influenza A/imunologia , Vírus da Influenza B/imunologia , Influenza Humana/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Comorbidade , Hospitais Urbanos , Humanos , Lactente , Recém-Nascido , Vírus da Influenza A Subtipo H1N1/imunologia , Federação Russa/epidemiologia , Estações do Ano , Estudos Soroepidemiológicos , População UrbanaRESUMO
During three seasons at the period of 1992-1996 immunization of elderly persons, living in homes for old people, against influenza with inactivated influenza vaccine (IIV) was carried out. Altogether 856 persons were immunized intranasally, 581 persons constituting the control group. For comparison, 4,825 healthy young adults aged 18-24 years were immunized under similar conditions. The study revealed that the intranasal immunization of elderly persons with IIV, made in two administrations, was safe and stimulated sufficient humoral and secretory immunity: the level of seroconversions was 24.3-41.0% to type A(H1N1) influenza virus, 29.6-50.7% to type A(H3N2) influenza virus, 39.3-59.6% to type B influenza virus; the level of diagnostic IgA conversions was 31-38%. Immunization produced a pronounced prophylactic effect (the effectiveness index 1.6-1.7), as well as decreased the total mortality level by half. The tactics of the immunization of persons from high risk groups against influenza in medical practice is discussed.