basic reproduction number
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basic reproduction numberA metric used in epidemiology, which corresponds to the mean number of new cases of infection linked to a person infected shortly after the pathogen was introduced into a population with no pre-existing immunity, in absence of interventions to control the infection. The basic reproduction number is a dimensionless parameter which encapsulates the biological details of different transmission mechanisms.
For microparasites, Ro is defined as the average number of secondary cases of infection to which one primary case gives rise throughout its infectious period if introduced into a defined population consisting solely of susceptible individuals; for macroparasites, Ro is the average number of female offspring (or offspring for hermaphroditic species) produced throughout the lifetime of a mature female parasite, which themselves achieve reproductive maturity in the absence of density-dependent constraints on the parasite establishment, survival or reproduction