|Abstract: Infectious diseases have been emerging at an increasing rate in both humans and wildlife due to increasing anthropogenic disturbance of natural ecosystems, and are now a well-recognised threat to biodiversity conservation. The threat posed to apes by this encroachment is heightened by the susceptibility of these species to human infectious diseases. A previous study in the vicinity of the Mikongo Conservation Centre (MCC) in Lope National Park, Gabon, identified the zoonotic protozoal pathogens, Cryptosporidium sp. and Giardia sp. in a western lowland gorilla (Gorilla gorilla gorilla) population close to areas of human disturbance. By detecting these parasites and identifying the genetic assemblages present in the local gorilla, human and livestock populations, this project will investigate the use of these protozoa as markers of cross-species disease transmission, and therefore assess the risk of this transmission to these host species.