It is an ill wind that blowflies nobody any good! Lucilla sericata does get a bad press because it flits between the kitchen and midden with sticky feet - without even getting as far as laying eggs. But it has a useful side as well; as was brought home to me by some of our Pharmacy Technician students. They had been formed into groups, each to do a small independent research project, summarise their findings in a poster and present it all at an academic meeting later in the year. There's €250 riding on the best poster from The Institute and more prizes at the national meeting. The Faculty from the PT course were each assigned to mentor a poster-group and mine elected to write about the uses of leeches and blowfly larvae in wound debridement. Most PTs choose to work in community pharmacies but others go for work in a hospital pharmacy where they deal almost exclusively with medical professionals rather than anxious parents and dithery ancients. One of the jobs of a hospital pharmacy is to feed the leeches Hirudo medicinalis! These lads are closely related to the earthworms that rummage through my compost heap but they depend on a blood meal rather than deco posibg vegetation. You can pick up leeches if you wade through the water where they live - which was all over Europe and much of West Asia.
They are in hospital pharmacies for their saliva which is a rich stew of anti-coagulants: to stimulate the blood flow y'know. If the surgeon clamps a couple on after a microsurgical finger re-attachment, then these secrations keep the blood circulating in the area and promote healing. Very retro, not to say medieval, but they are in some circumstances the best tool in the box.
In the bed next to Jimmy with accident chopping kindling, old Mrs Doohickey is nursing some weeping sores on her lower legs: her diabetes doesn't help but the primary cause is an antibiotic resistant tuberculosis infection. Because she's old and quite crocked up (the diet of cigarettes and biscuits doesn't help) her immune system just isn't clearing up the wound. The nurses have to change the dressings twice a day and the smell is funky. Part of the problem is that the resident bacteria are working away underneath a thick biofilm of dead and dying cells - both Mrs D.'s and her spongers' and what's left of her immune system is overwhelmed. Bring on the dancing blowfly larvae! These aren't on the inventory of the Pharmacy but can be ordered up from a convenient supplier. The larvae come cleaned! so that they don't make things worse by adding more microbes to the soup. It is also required that they are applied to the gaping wound under a maggot-proof dressing - nobody wants t'buggers crawling out between the sheets and dropping to the floor like a scene from the Great Escape. Amazingly, the larvae = maggots prefer the soupy elements of the lesion and eat everything back to sound tissue which is then able to start the healing process. Surgeons are taught debridement in med school - cleaning up ragged wounds so that the can be sewn up but the scalpel or more usually a curette is a rough bludgeon compared the delicate rasp of the larva's mouth-parts.
- What about The Mother in the title?
- Where do you suppose the eggs come from which hatch into larvae and debride the mess?
- Do you always answer a question with a question?
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