With the rising frequency of pathogen spillover worldwide, wildlife disease dynamics have received increased attention. There are many possible pathway a pathogen can invade and spread through a host population, and the assumed transmission model used to capture disease propagation can influence predictions of pathogen net reproductive success (R0), determining the outbreak dynamics. We synthesize a comprehensive overview of these models and overarching implications, using bovine Tuberculosis (Mycobacterium bovis) as a case study. We unify sub-models from the disease ecology literature and clarify the biological motivation behind these models and resulting ecological dynamics. We warn readers of pitfalls regarding the relative orders of the transmission parameters and reiterate that the contact rate determines the transmission model and thus defines key dynamical properties of an outbreak. Transmission in wildlife is linked to ecosystem and human health, and host community structure can mediate pathogen spread. We link these models with disease-biodiversity theories, by considering the role of host diversity in disease transmission, contributing to the debate on the effect of biodiversity and on disease outbreak potential. We decompose the various mechanisms of transmission in a stepwise process, and provide the reader a guide for modelling pathogens in both single-host and multi-host systems.