Pharyngeal Communities and Antimicrobial Resistance in Pangolins in Gabon.

Wildlife can be a reservoir and source of zoonotic pathogens for humans. For instance, pangolins were considered one of the potential animal reservoirs of SARS-CoV-2. The aim of this study was to assess the prevalence of antimicrobial-resistant species (e.g., extended-spectrum ß-lactamase [ESBL]-producing Enterobacterales) and Staphylococcus aureus-related complex and to describe the bacterial community in wild Gabonese pangolins. The pharyngeal colonization of pangolins sold in Gabon (n = 89, 2021 to 2022) was analyzed using culture media selective for ESBL-producing Enterobacterales, S. aureus-related complex, Gram-positive bacteria and nonfermenters. Phylogenetic analyses of ESBL-producing Enterobacterales was done using core-genome multilocus sequence typing (cgMLST) and compared with publicly available genomes. Patterns of cooccurring species were detected by network analysis. Of the 439 bacterial isolates, the majority of species belonged to the genus Pseudomonas (n = 170), followed by Stenotrophomonas (n = 113) and Achromobacter (n = 37). Three Klebsiella pneumoniae isolates and one Escherichia coli isolate were ESBL-producers, which clustered with human isolates from Nigeria (MLST sequence type 1788 [ST1788]) and Gabon (ST38), respectively. Network analysis revealed a frequent cooccurrence of Stenotrophomonas maltophilia with Pseudomonas putida and Pseudomonas aeruginosa. In conclusion, pangolins can be colonized with human-related ESBL-producing K. pneumoniae and E. coli. Unlike in other African wildlife, S. aureus-related complex was not detected in pangolins. IMPORTANCE There is an ongoing debate if pangolins are a relevant reservoir for viruses such as SARS-CoV-2. Here, we wanted to know if African pangolins are colonized with bacteria that are relevant for human health. A wildlife reservoir of antimicrobial resistance would be of medical relevance in regions were consumption of so-called bushmeat is common. In 89 pangolins, we found three ESBL-producing Klebsiella pneumoniae strains and one ESBL-producing Escherichia coli strains, which were closely related to isolates from humans in Africa. This points toward either a transmission between pangolins and humans or a common source from which both humans and pangolins became colonized.

Identification of novel orthonairoviruses from rodents and shrews in Gabon, Central Africa.

In Africa, several emerging zoonotic viruses have been transmitted from small mammals such as rodents and shrews to humans. Although no clinical cases of small mammal-borne viral diseases have been reported in Central Africa, potential zoonotic viruses have been identified in rodents in the region. Therefore, we hypothesized that there may be unrecognized zoonotic viruses circulating in small mammals in Central Africa. Here, we investigated viruses that have been maintained among wild small mammals in Gabon to understand their potential risks to humans. We identified novel orthonairoviruses in 24.6 % of captured rodents and shrews from their kidney total RNA samples. Phylogenetic analysis revealed that the novel viruses, Lamusara virus (LMSV) and Lamgora virus, were closely related to Erve virus, which was previously identified in shrews of the genus Crocidura and has been suspected to cause neuropathogenic diseases in humans. Moreover, we show that the LMSV ovarian tumour domain protease, one of the virulence determination factors of orthonairoviruses, suppressed interferon signalling in human cells, suggesting the possible human pathogenicity of this virus. Taken together, our study demonstrates the presence of novel orthonairoviruses that may pose unrecognized risks of viral disease transmission in Gabon.

Identification of potential novel hosts and the risk of infection with lymphocytic choriomeningitis virus in humans in Gabon, Central Africa.

OBJECTIVES: Lymphocytic choriomeningitis virus (LCMV), a human pathogenic arenavirus, is distributed worldwide. However, no human cases have been reported in Africa. This study aimed to investigate the current situation and potential risks of LCMV infection in Gabon, Central Africa. METHODS: A total of 492 human samples were screened to detect LCMV genome RNA and anti-LCMV IgG antibodies using reverse transcription-quantitative PCR and enzyme-linked immunosorbent assay (ELISA), respectively. ELISA-positive samples were further examined using a neutralization assay. Viral RNAs and antibodies were also analyzed in 326 animal samples, including rodents, shrews, and bushmeat. RESULTS: While no LCMV RNA was detected in human samples, the overall seroprevalence was 21.5% and was significantly higher in male and adult populations. The neutralization assay identified seven samples with neutralizing activity. LCMV RNA was detected in one species of rodent (Lophuromys sikapusi) and a porcupine, and anti-LCMV IgG antibodies were detected in four rodents and three shrews. CONCLUSIONS: This study determined for the first time the seroprevalence of LCMV in Gabon, and revealed that local rodents, shrews, and porcupines in areas surrounding semi-urban cities posed an infection risk. Hence, LCMV infection should be considered a significant public health concern in Africa.

Identification and molecular characterization of novel primate bocaparvoviruses from wild western lowland gorillas of Moukalaba-Doudou National Park, Gabon.

Bocaparvoviruses have been studied extensively owing to their ability to cause respiratory illness or gastroenteritis in humans. Some bocaparvoviruses have been detected in non-human primates (gorillas and chimpanzees), but the diversity and evolution of these viruses are not fully understood. In this study, we collected 107 fecal samples from wild western lowland gorillas in Moukalaba-Doudou National Park in Gabon to investigate the presence of bocaparvoviruses. Using a combination of pan-bocaparvovirus PCR and individual identification by microsatellite genotyping, we found that two samples from two apparently healthy infant gorillas were positive for bocaparvovirus. Sequencing and phylogenetic analyses revealed that the two gorilla bocaparvovirus strains are nearly identical and are closely related to viruses in the species Primate bocaparvovirus 2 (with 86.0% nucleotide identity to a human bocavirus 2 isolate). To our knowledge, this is the first report showing the presence of a non-human primate bocaparovirus within Primate bocaparvovirus 2. Our findings provide novel insights into the diversity and evolution of bocaparvoviruses and highlight the importance of surveying these viruses for the safe management of gorilla-based ecotourism.

Male genetic structure and paternity in western lowland gorillas (Gorilla gorilla gorilla).

The male dispersal patterns of western lowland gorillas (WLGs, Gorilla gorilla gorilla) are not well understood. To determine whether most silverbacks stay close to their relatives, we analyzed autosomal and Y-chromosomal microsatellites (STRs) in wild WLGs at Moukalaba, Gabon. We obtained STR genotypes for 38 individuals, including eight silverbacks and 12 adult females in an approximately 40 km(2) area. Among them, 20 individuals were members of one identified group (Group Gentil; GG), including one silverback and six adult females. The silverback sired all 13 of the offspring in GG and no Y-STR polymorphism within GG was found, as expected in a one-male group structure. Over all silverbacks sampled, Y-STR diversity was high considering the limited sampling area, and silverbacks with similar Y-STR haplotypes were not always located in nearby areas. Although the misclassification rate of kinship estimates in this study was not negligible, there were no kin dyads among all silverbacks sampled. These results suggest that silverbacks born in the same group do not stay close to each other after maturation. The Y-STR diversity in this study was similar to that of a previous study conducted in an area that was approximately 150 times larger than our study area. Similarity of WLG Y-STR diversity between studies at different sampling scales suggests that male gene flow may not be geographically limited. These results suggest that WLG males normally disperse from their natal areas after maturation, at least, in Moukalaba.

Concurrent chikungunya and dengue virus infections during simultaneous outbreaks, Gabon, 2007.

An outbreak of febrile illness occurred in Gabon in 2007, with 20,000 suspected cases. Chikungunya or dengue-2 virus infections were identified in 321 patients; 8 patients had documented co-infections. Aedes albopictus was identified as the principal vector for the transmission of both viruses.