Fig. 1.

Potential roles of dogs in the transmission of pathogens. Dogs transit between wildlife environments and urban areas, interacting with wild animals and humans. Dogs can transmit pathogens to wild animals (A) and to humans (B, zoonotic diseases). Transmission of pathogens from wild animals to dogs (C) and the subsequent transmission of the pathogen to humans (D) is less likely because the pathogen would need to cross a number of barriers. However, considering the existence of multi-host pathogens, the role of dogs as “spillover bridge” is possible and should not be overlooked. Moreover, dogs can transport pathogen vectors (e.g., ticks) from wild animals to humans, facilitating human infection with pathogens derived from wild animals. Finally, the role of dogs as mediators of reverse-zoonosis (E, pathogen transmission from humans to wild animals) is little studied and should be evaluated in greater detail. See text for references.

This figure was created using Mind the Graph illustrations (available at www.mindthegraph.com).