Do the diseases we’d almost forgotten about still exist today? Patrick Pollock FRCVS sheds new light on old problems
These marble-sized lumps are the work of the warble fly, whose correct name, Hypoderma, gives you an idea of its intent (from the Greek “hypo”, meaning under, and “derma”, meaning dermis or skin).
The fly lays eggs on a variety of animals – usually cattle, but also horses, sheep and occasionally humans. The eggs hatch and the larvae set off on their journey to their preferred site for development – usually the fat along each side of the dorsal spinous processes of the vertebrae or, for another species of the fly, the tissue around the oesophagus. They can migrate as far as the brain, causing severe and fatal neurological disease.