The medicinal leech and its use in plastic surgery: a possible cause for infection.

Recent interest in the use of the medicinal leech (Hirudo medicinalis) in microsurgical practice prompted us to undertake a bacteriological study. Aeromonas hydrophila was consistently cultured from 9 leeches that we examined. This organism is pathogenic to man and we consider that there is a significant risk of infection, particularly in those procedures where the vascularity of the tissues is compromised. There are several pharmacological preparations which have similar properties to the secretion of the medicinal leech and we submit that these non-infective preparations may be worthy of investigation.