Circulation of pathogens between wild great apes and humans attracts attention, apes might be reservoirs for diseases of man, and, reciprocally, human pathogens can have devastating effects on ape populations. Despite the long-term health monitoring of wild great apes at many sites, strongylid nematodes have been little studied so far. Our research on strongylid nematodes in gorillas and chimpanzees had uncovered the diversity of hookworms in studied hosts and provided molecular evidence that Necator species of great apes can infect humans and vice versa. The overall goal of proposed project is to study molecular diversity of hookworms in material from great apes and humans from model filed sites in Central African Republic, Cameroon and Guinea Bissau. We will (i) explore the interspecific and intraspecific variability of Necator spp. from wild apes and humans using next-generation sequencing (NGS), (ii) investigate the mixed infections, (iii) characterize the transmission patterns and factors responsible for the occurrence of primate originating Necator haplotypes/species in humans.