where D s is the duration of the specific contagious stage s and c n is the average number of contacts per person in network n (for close contacts, c n is 8, for casual ones, it is 24). Solving Equation 1 yields β s,n = − ln(1 − E s,n /c n ) D s (2) (2) we draw a random number r from an exponential distribution with mean 1/b s,n , (3) if r is smaller than the duration of the current contagious state D s , we schedule an infection event for the corresponding contact with delay r, otherwise the infection event is discarded. Infection events are stored in an event queue. At the scheduled time, it is checked whether the infection source is still contagious, the prospective victim is still susceptible and the contact between the two has not yet been impeded by interventions (e.g. isolation or seclusion) (see Table 1 ). The infection only takes place if all of these three conditions are fulfilled.