The larvae feed on decaying material that collects in drains. In natural settings, moth fly larvae feed on decaying plants and animals. They breathe through a tube that helps them survive even when their environment is very wet. Most moth flies are harmless to humans, though they may transmit bacteria and other microorganisms from their breeding sites to areas where people are. Moth flies do not bite.
Adults live about two weeks.
Most infestations originate in the building where the adults are found. Any aerosol or spray insecticide will easily kill the adults. However, for long-term control, the breeding sites must be found and removed, altered or treated. Inspect drain areas first, but consider all the potential breeding sites mentioned previously. If moth fly control is difficult, consider consulting a pest control operator or plumber.