Vertically Transmitted Diseases

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Infectious diseases are transmitted through various different mechanisms including person to person interactions, by insect vectors and via vertical transmission from a parent to an unborn offspring. The population dynamics of such disease transmission can be very complicated and the development of rational strategies for controlling and preventing the spread of these diseases requires careful modelling and analysis. The book describes current methods for formulating models and analyzing the dynamics of the propagation of diseases which include vertical transmission as one of the mechanisms for their spread. Generic models that describe broad classes of diseases as well as models that are tailored to the dynamics of a specific infection are formulated and analyzed. The effects of incubation periods, maturation delays, and age-structure, interactions between disease transmission and demographic changes, poulation crowding, spatial spread, chaotic dynamic behaviour, seasonal periodicities and discrete time interval events are studies within the context of specific disease transmission models. No previous background in disease transmission modelling and analysis is assumed and the required biological concepts and mathematical mwethods are gradually introduced within the context of specifric disease transmission models. Graphs are widely used to illustrate and explain the modelling assumptions and results.