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Yiga, F.

Publications and source records attributed to Yiga, F..

2 recordsLinked to original sources

Detection of diverse coronaviruses, paramyxoviruses, and rhabdoviruses from cave-dwelling bats in Eastern Uganda

Bats harbor a diversity of viruses, some of which have the potential to impact human and livestock health. Caves in Eastern Uganda are commonly inhabited by bats in the genera Rhinolophus, Hipposideros, Myonycteris, and others. Human encroachment into these caves for shelter, hunting, mineral harvesting, and tourism poses a risk of exposure to infectious agents these bats may carry, yet little is known about the viruses present in these bats. From 2021 - 2023, 635 unique bats were captured in caves by mist net, with 69 bats resampled over the study for a total of 706 sampling instances. A total of 1,394 oral and rectal swabs were collected non-destructively and screened using molecular techniques for coronaviruses, paramyxoviruses, rhabdoviruses, flaviviruses, and filoviruses. Of these samples, 399 (56.5%) were collected during the rainy season and 307 (43.5%) during the dry season. Coronavirus RNA was detected in 59/706 (8.36%) of samples from Rhinolophus spp. (n = 35), Hipposideros caffer (n = 12), Myonycteris angolensis (n = 6), and Miniopterus spp. (n = 6). Six bats (0.85%) were positive for paramyxoviruses. Finally, (3 H. caffer, 1 M. angolensis, 1 Rhinolophus spp. and 1 Nycteris thebaica) 3 Rhinolophus bats were positive for rhabdoviruses (0.42%, all Rhinolophus spp.). No samples were positive for filovirus or flavivirus RNA. This project has generated novel data on the association of bat species and different viral strains present in these bats, advancing our knowledge of viral ecology and spillover risk at the human/bat interface.

genomics↗

Whole genome sequencing-based characterization of mobile genetic elements in Staphylococcus aureus isolated from patients in Fort Portal Regional Referral Hospital, Western Uganda

BackgroundThe ability of Staphylococcus aureus to evolve through horizontal gene transfer mechanisms aids its success as a versatile pathogen. Mobile genetic elements (MGEs) are linked to potent virulence factors in S. aureus, e.g., the Panton-Valentine leukocidin and toxic shock syndrome toxins, as well as antibiotic resistance genes, e.g., mecA that encodes methicillin resistance. Despite their clinical relevance, molecular surveillance of MGEs in Africa remains limited. Here, we characterize the MGE repertoire of clinically relevant S. aureus isolates from Fort Portal Regional Referral Hospital (FPRRH), western Uganda. MethodsWe assembled a total of 40 genome sequences from previously sequenced S. aureus isolates cultured from patients (skin wounds, urinary tract, and bloodstream infections) at FPRRH during 2017-2019. spaTyper was used to determine the spa genotypes, while the presence of MGEs was screened and annotated for using PlasmidFinder, PHASTEST, Mobile Element Finder, SCCmecFinder, Bakta, MobileOG-db, and IslandViewer tools. ResultsEleven spa types were identified, with spa type t355 predominating. We detected 74 plasmid-derived sequences and 31 insertion sequences. Two SCCmec types, SCCmec type III and SCCmec type IV, were detected, indicating both hospital-associated MRSA (HA-MRSA) and community-associated MRSA (CA-MRSA). Forty-seven intact prophages (all Siphoviridae) were identified, carrying dfrG, sak, and lukPV genes. A total of 191 genomic islands were detected, and these harbored the virulence, immunoevasion, drug, and heavy metal resistance genes, such as nuc, tuf, tst, pvl, tet, blaZ, and mer genes. ConclusionsS. aureus at FPRRH harbors a diverse and functionally rich MGE repertoire, including genomic islands, prophages, insertion sequences, transposons, and plasmids, that contribute to the dissemination of virulence, AMR, and metal resistance determinants. The coexistence of HA-MRSA and CA-MRSA, as seen in other regions of Uganda, underscores the importance of continued genomic surveillance to inform infection control strategies.

genomics↗