Microbiological Ecological Surveillance of Zoonotic Pathogens from Hamadryas Baboons in Southwestern Saudi Arabia

Abstract

This study investigates parasitic and bacterial pathogens present in Hamadryas baboons (Papio hamadryas) and humans in southwestern Saudi Arabia. Fecal samples were collected from Hamadryas baboons (n = 999) from three city peripheries and humans from city centers (n = 1998) and peripheries (n = 1998) of southwestern and eastern Saudi cities. Parasitic examinations and bacterial cultures were conducted on these samples. Key findings include the identification of various parasitic and bacterial pathogens, with notable prevalences of Staphylococcus aureus (71.37% in baboons, 71.51% in humans), Blastocystis hominis (42.24% in baboons, 17.85% in humans), Cryptosporidium spp. (40.14% in baboons, 12.6% in humans), hookworms (37.44% in baboons, 18.57% in humans), Strongyloides spp. (37.34% in baboons, 17.39% in humans), Enterobius vermicularis (36.34% in baboons, 11.18% in humans), and Campylobacter spp. (29.73% in baboons, 1.86% in humans). Additionally, the prevalences of these microorganisms in human populations coexisting with baboons in southwestern city peripheries were 75.47%, 25.22%, 23.62%, 26.33%, 22.22%, 15.11%, and 3.8%, respectively. To further characterize bacterial isolates, 16S rRNA gene sequencing was used, suggesting potential zoonotic and anthroponotic cycles. The results highlight significant pathogen prevalence among both baboons and human populations in proximity to baboon habitats, indicating a potential public health risk. However, shared environmental sources, such as contaminated water, were not thoroughly assessed and could play a role in pathogen transmission. The study's focus on 18 different parasitic and bacterial pathogens allowed for the targeting of prevalent and indicative markers of zoonotic and anthroponotic transmission. In conclusion, these baseline data are crucial for the design of advanced studies to further investigate the zoonotic and anthroponotic transmission dynamics and the environmental factors influencing pathogen prevalence.

Keywords: Papio hamadryas; anthroponosis; pathogen coproprevalence; zoonosis; zoonotic infections.

Figure 1

Map and flow chart for sample source and abbreviations indicating cities’ geographical locations where coprosamples were collected (not to scale). Legend: Samples collected included 1998 human coprosamples from the southwestern city periphery (SCP) and southwestern city center (SCC), with 333 samples from each location. Additionally, 999 Papio hamadryas (PH) coprosamples were collected from the southwestern city periphery, with 333 samples from each location. Another set of 1998 human coprosamples was collected from the eastern city periphery (ECP) and eastern city center (ECC), with 333 samples from each location.