Some flies deposit their eggs on or near a wound or sore, the larvae that hatch burrow into the skin.
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.
Many of the flies do not lay eggs on humans. Instead, the flies lay their eggs on other insects (such as mosquitoes) or on objects (such as drying laundry) that may come into contact with people's skin. Eggs hatch into larvae, which burrow into the skin and develop into mature larvae.
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.
Hair heavily coated with fecal matter also becomes an inviting place for flies to lay eggs. The maggots feed on the organic matter, start to abrade the skin and then start to feed on live tissue.
What happens if I accidentally eat a fly's egg? Nothing will happen to you if you eat a fly egg.
Intestinal myiasis occurs when fly eggs or larvae previously deposited in food are ingested and survive in the gastrointestinal tract. Some infested patients have been asymptomatic; others have had abdominal pain, vomiting, and diarrhea (2,3). Many fly species are capable of producing intestinal myiasis.
Myiasis (“myi = fly”) is an infectious disease caused by invasion of vital and/or necrotic tissues by larvae of houseflies.
House fly eggs look like small grains of rice. Eggs hatch within 24 hours, and house fly larvae emerge. House fly larvae, or maggots, appear similar to pale worms.
House flies typically lay eggs on animal feces and garbage. White, legless maggots (the larval stage) hatch from the eggs and grow to about ½ inch.
While abroad, washing your clothes and leaving them to dry in the open air can lead to significant problems for the international traveller. In many of the hotter regions of the world a fly can actually lay her eggs on damp clothing which has been laid out to dry.
The fly lays its eggs on the ground or on bedding or clothing that is laid on the ground to dry and once hatched the larva seek the warm skin of humans which they penetrate rapidly.
The typical lesion associated with botfly myiasis is an erythematous, raised, furuncle-like lesion with central necrosis most commonly affecting the limbs [3]. Common symptoms associated with the skin lesions include itching, sensation of moving, and occasional lancinating pain [4].
Wound myiasis: occurs as a result of egg deposition on decaying flesh or pus-discharging wounds. If the maggots invade rather than staying on superficial layers of exposed tissue, subcutaneous nodules can result.
After several months to a year, the larvae pass through the feces to complete the maturation process. In most cases, botflies do not kill their host. However, sometimes the irritation caused by the larvae leads to skin ulceration, which can result in infection and death.
Botflies, also known as warble flies, heel flies, and gadflies, are a family of flies known as the Oestridae. Their larvae are internal parasites of mammals, some species growing in the host's flesh and others within the gut.
Life Cycle of House Flies
House fly eggs resemble individual grains of rice. Within a day, house fly eggs hatch into larvae, also known as maggots. Maggots are legless, white insects that feed from the egg-laying site for three to five days. During this time, maggots molt several times.
Individuals with myiasis may have general symptoms, including fever or lymphadenopathy (i.e., swollen glands). Furuncular myiasis typically presents as non-healing, boil-like lesions that may be purulent, painful, pruritic, and tender.
Researchers suspect that house flies can harbor at least 65 illnesses that infect people. Some of the most common house fly diseases transmitted in the U.S. include food poisoning, dysentery, and diarrhea. These pests may also transmit the eggs of parasitic worms, which cause their own issues.
House flies are strongly suspected of transmitting at least 65 diseases to humans, including typhoid fever, dysentery, cholera, poliomyelitis, yaws, anthrax, tularemia, leprosy, and tuberculosis. Flies regurgitate and excrete wherever they come to rest and thereby mechanically transmit disease organisms.
The most common symptoms of scabies, itching and a skin rash, are caused by sensitization (a type of “allergic” reaction) to the proteins and feces of the parasite. Severe itching (pruritus), especially at night, is the earliest and most common symptom of scabies.
In most instances, spotting a fly on your food doesn't mean you need to throw it out. While there is little doubt that flies can carry bacteria, viruses and parasites from waste to our food, a single touchdown is unlikely to trigger a chain reaction leading to illness for the average healthy person.
House fly eggs resemble small grains of rice. The eggs hatch into larvae, also known as maggots, which range in size from about ¼-3/8” (7-10 mm) long. Maggots are cream colored with a greasy appearance.
The House Fly
Keep in mind that flies feed on and lay eggs in anything that is rotting or putrefying. The likely breeding sites for house fly larvae indoors include animal carcasses, large numbers of dead insects, rotting meat or produce.