Several dozen larvae have been falling from this reader’s bathroom ceiling fan over a span of several days. The larvae appear to be white, have no legs, and, in the words of our reader, “one end” of the larvae “is flat and the other has a tapered pointy end.”
According to our reader, one-to-two dozen larvae have been falling per day. They are about 1/2-inch long and our reader guesses they are house fly larvae but would like us to confirm that identification. She adds that she is worried about the sheer number of them and wonders if we have any advice on how to get rid of them. She has lived in her “single family” wood-frame home in Boston for four years and has never seen the likes of this before.
First of all, we can indeed confirm that these are house fly larvae. House flies are generally known as the most common of household pests. The larvae of these critters will pretty much eat anything organic, and come in large numbers (hence our reader’s discovery of so many of these larvae). While this fact makes fly larvae excellent composting worms, it also makes them difficult to deal with when found in the home. During the course of their — very impressive — 30 day lifespan, houseflies can lay up to 1000 eggs.
Moreover, in terms of what our reader can do to combat this infestation, her best bet is probably cleaning out the bathroom ceiling fan. Usually, house fly eggs are deposited on a food source for the larvae. This would include rotting food, or a decomposing animal. This means there is probably something organic decomposing inside the fan that needs to be cleaned out. As with any infestation, cleaning out the source is the most important, and lucky for our reader, she has already found the source. We also recommend that our reader checks all her food items that may have been exposed to the elements for fly eggs, so as to make sure not to consume any. Flies can carry pathogens, so one needs to be sure they are not accidentally being consumed. The eggs are quite tiny, but are visible to the naked eye and resemble minuscule grains of rice.
In conclusion, the larvae that have been falling from the ceiling fan in our reader’s bathroom are definitely house fly larvae. Although fly larvae can pose a threat to human health, as they can carry pathogens, more than anything they are a nuisance. We are sure that if our reader cleans out her fan and ensures that no food or other organic matter is left out to decompose to attract new flies, her home will be fly-free soon.