This chap was strolling across my bathtub in Freetown, Sierra Leone, one day after very heavy rains and flash flooding. From its course, it appeared to have come up the bath plug from the drains.
It's about 2mm-3mm wide at the fattest points and 1mm wide at the thinnest points (which vary as it moves). It's maybe around 10cm in length. The picture's not the clearest but (to the naked eye) it looked almost completely featureless - smooth (no visible rings), and no obvious hooks or features at either end.
It was moving to the right from the point of view of the photo, and moved by narrowing and elongating unmarked segments about 2-4cm long each rather than the whole body. I say segments, since it seemed to be the same sections each time, but when it wasn't moving there was nothing to distinguish these segments. Its movements began by elongating the very front 2-3cm, then it'd feel around, come down, and other (unmarked) segments in the body would expand and contract to bring the rest of the body after it.
While I'm pretty sure it's not either of the two most notoriously nasty West African parasitic worms (Loa Loa or Guinea Worm), I didn't want to to take any chances, and we had nothing to isolate or store it in, so we carefully squashed this one after taking photos then cleaned the plug hole with boiling water and cleaner.
On squashing it, it burst in a very similar way to a recently-fed mosquito or bed bug with a splatter of what looked exactly like regular human/mammal blood. I've not seen this before from a worm. Each 5mm or so of worm body contained about as much blood as a well-fed mosquito.
I've done a little browsing of species of bloodworm but didn't find any obvious matches.
This might be unrelated, but the bathroom in which this worm surfaced has for several weeks had a small but constantly replenishing population of tiny flies like this, which I never questioned because they look almost exactly like regular drain flies. There's usually 1-3 of these flies on any given day, even after wiping out all of yesterday's flies, and I've not seen them anywhere else in the country. In this image it's about 3mm from wingtip to wingtip - much smaller than the worm.