Microbiota Dynamics: A Key Factor in Hirudotherapy-Related Infections?

The gastrointestinal microbiota of medicinal leeches is particularly interesting due to their blood-feeding habits, increasing medical use, and risk of pathogen transmission. Three groups of Hirudo verbana were used to study the leech microbiota: farmed leeches fasting for a long time, farmed leeches recently fed with bovine blood, and wild specimens fed with amphibian blood. The microbiota of the leeches' mouth, pharynx, crop, and intestine was analyzed. Metasequencing analyses were performed using amplification of the 16S rRNA V3-V4 region on a NovaSeq Illumina platform. The relative abundance of bacterial microbiota included environmental bacteria from the families Rhizobiaceae, Comamonadaceae, Sphingobacteriaceae, Phreatobacteraceae, Myxococcaceae, Chitinophagaceae, Rhodospirillaceae, and Bdellovibrionaceae, as well as symbiotic/probiotic bacteria such as Mucinivorans, Aeromonas, Vagococcus, Lactobacillales, and Morganella. Significant differences were found in the different regions of the digestive system among the three groups of leeches, and environmental bacteria were present in all groups to varying degrees. A negative correlation was found between the dominant environmental and the symbiotic/probiotic bacteria. In contrast, a positive correlation was found between environmental and symbiotic/probiotic bacteria, indicating their association with host factors. Microbiota diversity, abundance, and bacterial correlations may be influenced by factors such as the leech's fasting state, blood meal source, and environmental conditions. The identified opportunistic pathogens, such as Rickettsia, Anaplasma, and Treponema, identified for the first time in H. verbana, should be taken into consideration when using this leech in hirudotherapy. Our results show that extensive screening for opportunistic and pathogenic agents should be performed on leeches intended for medical use. Long-fasting leeches and leeches cultured in specialized farms are recommended for hirudotherapy.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

16S rRNA metagenomic study of leech gastrointestinal microbiota across mouth, pharynx, crop and intestine in farmed (fed/fasting) versus wild leeches. Identifies opportunistic pathogens and recommends long-fasting farm-raised leeches for hirudotherapy.

Узнайте, как это исследование связано с клинической практикой

More peer-reviewed studies in Безопасность и инфекционный контроль.

• Leech-Assisted Flap Salvage — Systematic Review of 277 Cases — Whitaker et al. (2012)
• Effects of hirudotherapy on liver functions, lipid profile, and insulin sensitivity in rats with metabolic syndrome — Bilden A et al. (2026)
• Efficacy and Safety of Hirudotherapy for Improving Sperm Quality Parameters in Male Infertility: A Randomized Controlled Trial — Abtahi-Forooshani M et al. (2026)
• Improvement of patient care through hirudotherapy and the management of leeches from their reception to their disposal in France — Vaesken C et al. (2023)
• Hirudotherapy in Medicine and Dentistry — Jha K et al. (2015)
• Management of Chronic Non-healing Wounds by Hirudotherapy — Iqbal A et al. (2017)
• Hirudotherapy attenuates arthritic pain in patients with various chronic pain syndromes: A retrospective analysis — Loeser J et al. (2020)
• Hirudotherapy (medicinal leeches) for treatment of upper airway obstruction in a dog — Trenholme H, Masseau I, Reinero C (2021)
• Analysis of antibiotic resistant infections associated with hirudotherapy — Brauer P et al. (2024)
• Leech Me Alone! Atraumatic Hemarthrosis after Hirudotherapy — Curcio J, Lloyd C (2020)

Browse all ASH-analysed research →