Host matters: medicinal leech digestive-tract symbionts and their pathogenic potential
Review published in Frontiers in Microbiology (2016)
Abstract
Digestive-tract microbiota exert tremendous influence over host health. Host-symbiont model systems are studied to investigate how symbioses are initiated and maintained, as well as to identify host processes affected by resident microbiota. The medicinal leech, Hirudo verbana, is an excellent model to address such questions owing to a microbiome that is consistently dominated by two species, Aeromonas veronii and Mucinivorans hirudinis, both of which are cultivable and have sequenced genomes. This review outlines current knowledge about the dynamics of the H. verbana microbiome. We discuss in depth the factors required for A. veronii colonization and proliferation in the leech crop and summarize the current understanding of interactions between A. veronii and its annelid host. Lastly, we discuss leech usage in modern medicine and highlight how leech-therapy associated infections, often attributable to Aeromonas spp., are of growing clinical concern due in part to an increased prevalence of fluoroquinolone resistant strains.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Comprehensive review of leech digestive-tract microbiota, focusing on Aeromonas veronii symbiont and its dual symbiont-pathogen potential in human infections.
Why This Matters for Hirudotherapy
This review summarizes current knowledge of the Hirudo verbana digestive-tract microbiome, which is consistently dominated by two cultivable, genome-sequenced species: Aeromonas veronii and Mucinivorans hirudinis. It discusses factors required for A. veronii colonization and proliferation in the leech crop, host-symbiont interactions, and the growing clinical concern of leech-therapy-associated infections—often attributable to Aeromonas spp.—including the increased prevalence of fluoroquinolone-resistant strains. This review is directly relevant to ASH's domain, as it addresses the microbial safety dimension of hirudotherapy with a medicinal leech species whose usage in modern medicine is noted. As a review, it synthesizes existing literature on symbiont biology and infection risk rather than presenting new experimental data.
Citation
Host matters: medicinal leech digestive-tract symbionts and their pathogenic potential.
Marden JN et al. · Frontiers in microbiology, 2016
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