Psychodinae, your common drain fly, have no interest in human hosts. While it's true that they lay eggs in organic matter, the human body is inhospitable to these tiny flying insects. Compare this to nastier species of Insecta and Diptera: botflies, blowflies and fleshflies.
No, this common household insect doesn't bite or sting. In fact, it rarely comes into contact with humans. Drain flies can spread bacteria but do not try and drink blood or eat human skin like other insects.
The female human Botfly lays her eggs on the body of an intermediate host, usually a mosquito, or fly, which acts as a vector onto the human skin when it feeds. The heat of the skin causes the eggs to hatch into larvae where they rapidly burrow themselves.
Their larvae have been known to be an opportunistic agent of myiasis—a parasitic infection of the body that can occur when the larvae enter the body—though this is quite rare. So, no, drain flies aren't likely to make you sick.
Drain flies gather, mate, and lay eggs in moisture or standing water. The slimy film that forms in sewers and drains is a favorite breeding spot. Putting off regular cleaning and maintenance of these areas may attract the pests and offer them a place to feed and develop.
Like really love it! They're attracted to moist places like bathroom drains or sink drains and moist towels where there is a lot of stagnant water for them to breed and lay their eggs.
Make a natural cleaning/fly killer mixture.
Mix together 1/2 cup of salt, 1/2 cup baking soda and 1 cup of vinegar. Pour the mixture down the drain. Let sit overnight, then flush the drain with hot water in the morning.
Some flies deposit their eggs on or near a wound or sore, the larvae that hatch burrow into the skin. Certain species' larvae will move deeper in the body and cause severe damage.
Typical symptoms of furuncular myiasis include itching, a sensation of movement, and sometimes sharp, stabbing pain. At first, people have a small red bump that may resemble a common insect bite or the beginning of a pimple (furuncle). Later, the bump enlarges, and a small opening may be visible at the center.
Drain flies are linked to microfilaria, which is a disease that affects animals. The larvae of the flies are harmful to the body when present in large numbers, and the microfilaria can cause watery eyes and nose and respiratory problems.
Scabies is a skin condition caused by the Sarcoptes scabiei var hominis mite. These little bugs make tunnels (burrow) under your skin and cause small red bumps and severe itching. Scabies spreads easily from person to person, especially among people who live close together.
Myiasis commonly resolves on its own as the larvae are sloughed within weeks. In cutaneous myiasis, however, larvae extraction may be aided by applying topical substances, like petroleum jelly and liquid paraffin, to assist the migration of the larvae out of the skin.
What if you see bites and have drain flies? Red and itchy bites on your skin are not from drain flies. If they are in fact bites, they could be from other insects found in your home.
Drain flies live off of whatever is in your drain. If it's partially clogged or there is food stuck somewhere, they will look for that organic material to sustain themselves. Drain flies are distinguishable by their fuzzy bodies, flat wings, and gray or tan color.
Drain flies don't bite or sting people or animals. However, if they die in your home, their decaying bodies can cause allergic reactions in some people. People with asthma may have trouble breathing because of the dust and fragments from their bodies, as well.
Diagnostic Findings. The diagnosis of myiasis is made by the finding of fly larvae in tissue. Identification to the genus or species level involves comparing certain morphological structures on the larvae, including the anterior and posterior spiracles, mouthparts and cephalopharyngeal skeleton, and cuticular spines.
Myiasis is rarely acquired in the United States; people typically get the infection when they travel to tropical areas in Africa and South America. People traveling with untreated and open wounds are more at risk for getting myiasis. Fly larvae need to be surgically removed by a medical professional.
Current treatment for wound myiasis requires debridement with irrigation to eliminate the larvae from the wound or surgical removal. Application of chloroform, chloroform in light vegetable oil, or ether, with removal of the larvae under local anesthesia, has been advocated for wound myiasis.
The eggs hatch into larvae, which burrow under the skin and begin to mature. The result is a red bump or furuncle that looks like a bug bite or pimple. As the fly larvae get larger, the spot might itch or hurt. You might feel like there's something moving under the skin.
Once the skin has been breached, the larvae then tunnel through the sores into the host's subcutaneous tissue, causing deep and irritating lesions highly subject to infection. After about the second day, bacterial infection is likely and, if left untreated, causes bacterial bloodstream infections or sepsis.
Wound myiasis
Surgical removal is not required unless requested by the patient, as the larvae are naturally sloughed within 5-7 weeks.
Essential oils are sometimes used to keep flies away from infested sections and also to kill them. Lavender, eucalyptus, peppermint, lemongrass, and citronella are just a few of the scents that insects despise (with lavender probably being the most effective).
One common remedy for killing drain flies is using household bleach. This is a very useful and cost-effective manner for getting rid of these little pests with an item you already have around the house.
Learn the Pest Biology
Life Cycle: Adult females lay 30–100 eggs in sludge around sewage and drainage areas. Eggs hatch in 32–48 hours, larval stage lasts 8–24 days, pupal stage 20–40 hours. Adults live about two weeks.