RNA VIRUS EVOLUTION, POPULATION-DYNAMICS, AND NUTRITIONAL-STATUS

Trace elements exert a strong influence on immune function. Debilitate d humoral and cellular immune responses may impair virus clearance in infected organisms, and favor the generation of virus variants with al tered biological properties. The population size in evolving viral qua sispecies, as well as increased mutagenesis triggered by oxidative str ess, may contribute to altering the outcome of quasispecies evolution in infected hosts. The genetic plasticity of RNA viruses is one of the main obstacles for the control of the diseases they cause and probabl y a major force in the emergence of new viral pathogens. Recent result s suggest links between nutritional deficiencies and the generation of variant viruses, a possibility that is addressed in the present artic le.