[The determination of the interdependence of the infectivity of different groups of birds with the influenza virus by using mathematical modelling].

When studying sera in the hemagglutination-inhibition reaction which has been taken from 772 fowls of 82 species caught in certain regions of the Dnieper in 1981-1987 the antibodies to 29 strains of the influenza virus are revealed, all of them being of human and animal origin. The serological examination has shown the circulation of the influenza virus with hemagglutinin H13 in a wide range of water fowls, the level of antibodies to it being dependent on the species of fowls and season. Using the mathematical simulation it was possible to establish the relation of the influenza virus infection in groups of semisynanthropic and tame fowls to the titre of antibodies determined in the synanthropic species as well as ecological insulation of the so-called "wild fauna".