The genus Strongyloides includes over fifty species, three of which are capable of infecting humans. Strongyloidiasis affects an estimated 600 million people worldwide, with a global distribution and foci of infection in tropical and subtropical regions. Strongyloides infections are also commonly reported in free-living and captive non-human primates (NHP). Strongyloides stercoralis has a cosmopolitan distribution and infects primarily humans, dogs, and captive NHP, whereas S. fuelleborni infects wild NHP in Africa and Asia and occasionally infects humans. Because of the close phylogenetic relationship between humans and NHP, especially great apes, pathogens are easily transmitted between them. More than 60 % of infectious agents known to be pathogenic to humans have an animal origin (are zoonotic), and the origin of many human pathogens is in NHP. Nevertheless, the transmission of parasites, including Strongyloides, under natural conditions is poorly studied. Therefore, the initial objective of this study is to investigate the occurrence of Strongyloides in various sympatric primates and humans in Cantanhez National Park (CNP) in Guinea-Bissau. There are over one hundred villages within the CNT, and the population living in the CNP has increased by 150 % in the last 60 years. For this reason, people live in close proximity to wildlife and come into contact with the NHP. The student will use previously collected biobank samples from humans (n=76) and several sympatric primates (Papio papio: n=50, Chlorocebus sabaeus: n=25, Colobus polykomos: n=40, Piliocolobus badius: n=29, Cercopithecus petaurista: n=53 and Pan troglodytes verus: n=139) living in CNP. Student will detect Strongyloides spp. in the investigated host species using an already developed qPCR protocol based on the 18S rRNA gene for the detection and quantification of Strongyloides at genus level. Students will be familiarised with basic molecular methods (e.g., DNA isolation, PCR, qPCR) and evaluate the prevalence of Strongyloides in humans and sympatric NHP. In addition, Strongyloides-positive samples will be selected and used for following master's study using more sophisticated methods such as high-throughput sequencing to determine the exact Strongyloides species and assess possible transmission between humans and NHP.