The analysis presented here will focus on deriving new estimators for individual and household reproduction numbers, denoted R (t ) and R * (t ) respectively. The individual reproduction number R (t ) is defined roughly as the average number of people someone infected at time t can infect over their entire infectious lifespan; as I will show below, there are several ways of defining this more precisely. The household reproduction number R * (t ) is defined here as the average number of households a household infected at time t can infect [3, 6] . The individual reproduction number R (t ) rightly plays a privileged role in epidemiology, as it is a meaningful measure within any contact network. However, of the possible summary measures of epidemic progress, it is not necessarily the most useful. For example, for an emerging directly transmitted pathogen, such as pandemic influenza virus, public health interventions may target the household rather than the individual, enforcing household quarantine as well as offering antivirals to the household to limit transmission within the household. In such a situation, the household reproduction number R * (t ) is more directly related to the parameters which characterize the intervention, and is thus a better measure of the effect of these interventions. These quantities (R (t ) and R * (t )) share the two essential properties of reproduction numbers, namely that they increase when infectiousness increases and decrease when infectiousness decreases (monotonicity), and that they mark a threshold that separates exponentially growing epidemics (when R (t ).1 or equivalently R * (t ).1) from exponentially declining epidemics (when R (t ),1 or equivalently R * (t ),1) [3, 6] .