What’s the risk? Identifying potential human pathogens within grey-headed flying foxes faeces

Abstract

Pteropus poliocephalus (grey-headed flying foxes) are recognised vectors for a range of potentially fatal human pathogens. However, to date research has primarily focused on viral disease carriage, overlooking bacterial pathogens, which also represent a significant human disease risk. The current study applied 16S rRNA amplicon sequencing, community analysis and a multi-tiered database OTU picking approach to identify faecal-derived zoonotic bacteria within two colonies of P. poliocephalus from Victoria, Australia. Our data show that sequences associated with Enterobacteriaceae (62.8% ± 24.7%), Pasteurellaceae (19.9% ± 25.7%) and Moraxellaceae (9.4% ± 11.8%) dominate flying fox faeces. Further colony specific differences in bacterial faecal colonisation patterns were also identified. In total, 34 potential pathogens, representing 15 genera, were identified. However, species level definition was only possible for Clostridium perfringens, which likely represents a low infectious risk due to the low proportion observed within the faeces and high infectious dose required for transmission. In contrast, sequences associated with other pathogenic species clusters such as Haemophilus haemolyticus-H. influenzae and Salmonella bongori-S. enterica, were present at high proportions in the faeces, and due to their relatively low infectious doses and modes of transmissions, represent a greater potential human disease risk. These analyses of the microbial community composition of Pteropus poliocephalus have significantly advanced our understanding of the potential bacterial disease risk associated with flying foxes and should direct future epidemiological and quantitative microbial risk assessments to further define the health risks presented by these animals.

A One Health investigation of Salmonella enterica serovar Wangata in north-eastern New South Wales, Australia, 2016–2017

“…Whilst bats/flying foxes are known vectors for viral pathogens in Australia, their carriage of bacterial pathogens is less well understood. In a recent study in Melbourne, Australia, Salmonella was isolated from two flying fox colonies and a daily load of 4 × 10 6 organisms was estimated [22]. However, this study was only able to identify S. enterica species and was unable to calculate the risk to human health.…”

Is the gut microbiota bacterial abundance and composition associated with intestinal epithelial injury, systemic inflammatory profile, and gastrointestinal symptoms in response to exertional-heat stress?

“…Extracted genomic DNA was delivered to Micromon Next Generation Sequencing Facility (Monash University, Clayton, Australia) for PCR amplification of the 500bp region of the 16S rRNA gene using established methods, but with additional modifications to enhance amplification, as previously described. 26,27 The assembled reads were analysed using the QIIME2 (v.2019.1) open-reference operational taxonomic units picking workflow for taxonomic identity assignment. Reads were imported into QIIME2 with quality assessment, filtering, barcode trimming, and chimera detection were performed using the DADA2 pipeline.…”

MR1-Restricted T Cells with MAIT-like Characteristics Are Functionally Conserved in the Pteropid Bat Pteropus alecto

“…The reason why pteropodid bats have hMAIT cell-like MR1T cell population beyond the putative selection and co-evolution with MR1 (Boudinot et al, 2016) is unclear. Previous studies show that frugivorous bats, including pteropodid bats, harbor large numbers of bacteria in their gastrointestinal tract dominated by large families of gram-negative bacteria, including Enterobacteriaceae, Moraxellaceae, and Pasteurellaceae (Buckles, 2015;Claudio et al, 2018;Heard et al, 1997;Henry et al, 2018). Members of these gramnegative families are capable in riboflavin biosynthesis (Constantinides et al, 2019;Gutierrez-Preciado et al, 2015;Schmaler et al, 2018;Tastan et al, 2018), a prerequisite for the production of the riboflavinrelated metabolites driving MAIT cell development, expansion and activation (Constantinides et al, 2019;Legoux et al, 2019;Schmaler et al, 2018;Tastan et al, 2018).…”