Black fly disease. . Domestic animals, especially poultry and exotic birds, can be killed by black fly attacks. Black flies are active spring through summer and bites are most common during spring. Onchocerciasis (pronounced “on-koh-ser-kai-uh-sis”), also called “river blindness,” is a disease caused by Onchocerca volvulus, a parasitic worm. Note that hunting and dressing game animals may bring you into close contact with infected ticks. Onchocerciasis, often referred to as "river blindness", is caused by the parasitic nematode Onchocerca volvulus, which black flies transmit through their bites. Onchocerciasis – or “river blindness” – is a parasitic disease caused by the filarial worm Onchocerca volvulus transmitted by repeated bites of infected blackflies (Simulium spp. Onchocerciasis, or river blindness, is a skin and eye disease caused by a microscopic parasitic worm Black flies have aggressive bites that can cause allergic reactions or infections. In tropical America and Africa, black flies may be parasitized by the nematode worm, Onchocerca volvulus, which can be transferred to other victims causing the disease onchocerciasis, resulting in blindness if the worms settle in the eye. Black Flies: Research and General Information Adult black flies are small insects of the family Simuliidae, about the size of a Drosophila fruit fly. They are found around rivers, and increase following heavy rain or flooding. Black flies are usually black or dark gray, with gauzy wings, stout antennae and legs, and rather short mouthparts that are adapted for sucking blood. When a fly bites, the nematode is transferred into the bloodstream where it can migrate to the eyes, causing blindness. What is river blindness? River blindness, also called ‘onchocerciasis’, is a neglected tropical disease caused by a bite from an infected black fly. Onchocerciasis is a parasitic disease caused by the filarial nematode worm Onchocerca volvulus. Of nine simuliid-borne animal diseases, only two, mansonellosis and onchocerciasis, afflict humans. It is transmitted to humans by black flies (genus Simulium) and can cause severe skin and eye disease, including blindness. This disease is transmitted to humans through the bite of infected black flies, primarily of the Simulium species. Here’s how to tell if a black fly bit you and what to do next. Many pathogens and parasites are transmitted by black flies to domesticated animals and wildlife, causing diseases such as bovine onchocerciasis, avian leucocytozoonosis, and vesicular stomatitis. In horses Black flies, or buffalo gnats, of the genus Simulium are dipterans that have an essentially free-living life cycle during which the adult males and females blood feed on a variety of mammals, including people, and birds. Dec 31, 2025 · Black flies are biting pests that do not transmit diseases to humans in the United States, but they can transmit parasitic nematodes in other regions. Learn how to spot different types of fly bites and how to treat them. Meanwhile, non-biting black flies make pests of themselves by flying around people’s heads and crawling into their ears, eyes, nose, and mouth. Besides being a nuisance to humans, black flies can pose a threat to livestock. Black fly disease, also known as "river blindness" or onchocerciasis, is a parasitic infection caused by the nematode Onchocerca volvulus. WHO works with partners to provide education and improve awareness so that people know how to protect themselves and their communities from mosquitoes, ticks, bugs, flies and other vectors. In humans, the parasitic worms live under the skin (subcutaneous nodules) and produce larvae (microfilariae). Black flies, gnats or buffalo gnats bite people and many different animals. Their arched thorax gives the flies the appearance of a miniature bison, accounting for one of their common names: “buffalo gnat. Lady Jean Wilson, Sightsavers’ co-founder and the wife of Sir John Wilson, coined the term river blindness, which is now widely used. Learn more about onchocerciasis. These blackflies breed along fast-flowing rivers and streams, close to remote villages located near fertile land where people rely on agriculture. Simulium control in other parts of the world centers on the insect’s ability to vector disease, primarily a type of subcutaneous filariasis called onchocerciasis (river blindness). Unlike many mosquito species, black fly actively seek blood meals during the day. What Are Sand Flies? The common name "sand fly" at times is applied to members of the biting midge family Ceratopogonidae and the black fly family Simuliidae, but it usually is reserved for blood-sucking species in the subfamily Phlebotominae of the family Psychodidae. Onchocerciasis is an infectious disease that can cause blindness and permanent skin damage. In humans, this systemic reaction is known as "black fly fever" and is characterized by headaches, fever, nausea, adenitis, generalized dermatitis, and allergic asthma. Yes, they have been known to transmit diseases to humans and animals. There also is so-called “black fly fever,” a collection of symptoms including headache, upset stomach, and fever. The disease is commonly known as "river blindness" because the larvae of the blackfly vectors breed in fast flowing rivers. In parts of Africa and Central and South America, black fly are the vectors of Onchocerciasis, or river blindness. However, black flies in temperate zones, such as North America and Europe, are generally not known to transmit diseases to humans. WHO fact sheet on vector-borne diseases, including key facts, overview, and WHO response. Black Tsetse flies (/ ˈsiːtsi / SEET-see, UK: / ˈtsɛtsə / TSET-sə or US: / ˈtsiːtsi / TSEET-see) (sometimes spelled tzetze; also known as tik-tik flies) are large biting flies that inhabit much of tropical Africa. The larvae are found throughout the body, but especially in the skin and eyes. During a blood meal, an infected blackfly (genus Simulium) introduces third-stage filarial larvae onto the skin of the human host, where they penetrate into the bite wound . The condition is most prevalent in sub-Saharan Africa, parts of Latin America, and Yemen. When a black fly bites an infected patient, larvae known as microfilariae that live in the patient’s skin enters the body of the fly, infecting it with the parasite in turn. In North America, black flies do not spread disease, but their bites can cause swelling, bleeding, pain and itching. The observations lasted from 1 to 30 days after the bites, depending on the persistence of the various disease signs in individual patients. In Africa, Central America and South America, adult black flies can transmit two diseases to humans: onchocerciasis, known as “river blindness”. During follow-up visits, the course of the disease was monitored until the local lesions and systemic reactions induced by the blackfly bites disappeared. These are Prosimulium mixtum and Simulium venustum. However, in certain regions of the world, such as equatorial Africa and parts of Central and South America, black flies can transmit the parasitic nematode worm Onchocerca volvulus, which causes onchocerciasis, also known as “river blindness”. However, in Africa, Mexico, Central America, Brazil, Venezuela and Yemen, they can transmit nematodes (i. The exact species of black fly responsible for transmitting the parasite may vary depending on the location. Both humans and livestock are Mansonellosis, a mildly pathogenic simuliid-borne disease of humans, occurs in scattered foci in Latin America. In Africa, Central America, and South America, they spread two significant diseases: onchocerciasis, or “river blindness”, and mansonellosis. The filarial worms that cause this disease are picked up when the black fly takes a blood meal, where it develops within the fly’s body. Black flies are not known to transmit diseases to humans in the United States. In addition to being vectors of disease agents, black flies pose other threats to livestock. This study describes a case of blackfly fever and dermatitis following blackflies numerous bites in Iran. Consider protecting your pet through the use of tick and tickborne disease prevention products for animals. The host's reaction to fly attacks may include systemic illness, allergic reactions or even death, presumably mediated by histamine. Only the females bite, causing extreme, sometimes fatal, loss of blood. Black flies (Diptera: Simuliidae) are one of the most important bloodsucking insects, and some of them are incriminated as vectors of the filarial nematode, Onchocerca volvulus, which is the The flies may enter noses, ears and mouths, causing further discomfort. Also known as river blindness, it is an infectious disease that is transmitted from person to person by the black fly. Learn more about the symptoms of a black fly bite and how to treat In addition to the nuisance effects, certain species of black flies may transmit various diseases, including leucocytozoonosis, a disease of turkeys, geese, ducks, and sometimes chickens. The source of onchocerciasis is the parasite Onchocerca volvulus. The parasite can spread to humans through repeat bites of infected blackflies of the Simulium species. Black flies attack most severely about sunrise and at sunset -- either massively and viciously or in such small numbers that they are scarcely noticeable. Black Flies: What, Where, When and Why What Are Black Flies? Black flies are tiny, blood-sucking flies in the insect family Simuliidae and are often called buffalo gnats or turkey gnats. Learn whether they make you sick and how to protect yourself from them. Black fly, (family Simuliidae), any member of a family of about 1,800 species of small, humpbacked flies in the order Diptera. These aren’t the same ones that transmit the disease, but they can assist scientists in finding ways to prevent it. Onchocerciasis is a debilitating disease infecting an estimated … Linking a disease to knowledge of its vector: River blindness and black flies If communities are to be involved in programmes to control insect- transmitted parasitic diseases prevalent in their locality, knowledge of the link between disease and vector is needed. There are few literature reports of blackfly fever following Simulium spp. Remember, black flies can also transmit diseases to both humans and wildlife, so it is essential to take preventative measures when spending time outdoors in their presence. e. A black fly is a type of insect belonging to the genus Simulium, which is known to transmit a parasite that causes a disease called river blindness. While black flies are not known to transmit disease to humans in the United States, human deaths (presumably from allergic reactions) have been reported. [1][2][3] Tsetse flies include all the species in the genus Glossina, which are placed in their own family, Glossinidae. Repeated bites by infected flies increase the number of adult worms and larvae. More than 2000 species of black flies feed on vertebrate blood; 1. Case presentation The A black fly bite can cause mild symptoms, such as swelling, redness and itching at the site. Overview Black flies, also known as buffalo gnats, are small, biting flies that irritate people and animals that live, work, or play near running rivers and streams. Even without transmission of pathogens, black fly biting can affect human and animal welfare through nuisance In North America, black flies are not known to transmit any diseases. Does it exist? Hilary Hurd 12 Nov 2021 An adult black fly. Nematode infections in adult female black flies have been reported from … Black flies are very tiny, blood-sucking flies that can cause death in animals and poultry due to blood loss, irritation, shock, and suffocation. Black flies breed in white water in rivers and streams, are strong fliers and tend to attack in swarms. There has been no documentation of black flies transmitting West Nile Virus to date. Fly bites What it looks like: There are a few major fly species that bother people in the United States, including deer, horse, stable, and black flies. The flies may enter noses, ears and mouths, causing further discomfort. They are capable of transmitting a number of different disease agents to livestock, including protozoa and nematode worms, none of which cause disease in humans. The parasite is spread and transmitted to humans by the repeated bites of infected blackflies that breed in rapidly flowing rivers. However, they transmit one parasitic nematode worm that infects humans in other regions of the world. Studying black flies at UGA is easy, as they have the only black fly colony in the world. They usually breed in fast moving water of streams and rivers. Many people infected with the parasite that causes onchocerciasis never show any symptoms. The larvae (immature worms) that cause the disease can take 12 – 18 months to develop into adults, when they start to reproduce inside a person's body. Meet the culprit Flies do more than pester people—they can spread disease. This does not transmit disease but can cause a small wound or severe swelling. You will not get Lyme disease from eating game meat, but in keeping with general food safety principles, always cook meat thoroughly. Black flies or blackflies[2] (sometimes called buffalo gnats, turkey gnats, or white socks) are flies in the family Simuliidae of the Culicomorpha infraorder. , died at the age of 84. The Rev. ). roundworms) causing river blindness (onchocerciasis) in humans. Background Besides the considerable role of blackflies to the transmission of many disease agents, these flies considered as annoying biting pests of wildlife, livestock, poultry, and humans. Are Black Flies a Public Health Risk? Black flies can be annoying biting pests, but none are known to transmit disease agents to humans in the U. Onchocerca volvulus causes a significant human disease known as onchocerciasis or "river blindness" in equatorial Africa and mountainous regions of northern South America and Central America. Jesse Jackson, one of the world's best-known Black activists who worked alongside Martin Luther King Jr. The quest for blood drives the pest Black flies (Diptera: Simuliidae) are insects of medical and veterinary importance because some of them are vectors of human and livestock disease agents. Simuliidae are related to the Ceratopogonidae, Chironomidae, and Thaumaleidae. Across wide swaths of Africa, one such nasty illness is a parasitic infection called “river blindness” (onchocerciasis). Black flies appear in early summer and late spring, appearing dark in appearance. Repellents are not always effective but may provide some help. Large numbers of black flies can cause bird and livestock death as well as cause a stamped, trampling of young, structure crashing and tumbling. Black flies (Diptera: Simuliidae) are significant pests and vectors of parasites transmitted to humans and other animals, including the causal agents of human onchocerciasis, one of the most significant neglected tropical infectious diseases. Onchocerciasis is caused by a nematode carried by black flies. The parasite is found in more than 100,000 communities in 31 African countries, 6 Latin American countries, and Yemen. ” Female black flies typically require a blood meal to mature their eggs. Onchocerca volvulus causes a significant human disease known as onchocerciasis or "river blindness" in equatorial Africa and mountainous regions Black flies serve as vectors of human and animal diseases in some areas of the world. How-ever, they transmit one parasitic nematode worm that infects humans in other regions of the world. They bite painlessly so that you may not be aware of having been attacked until small droplets of blood start oozing from your skin. 5% of all species are vectors of pathogens that cause human diseases. In general, biting black fly species tend to breed most abundantly at the outlets of ponds and lakes, perhaps because of more abundant food or warmer temperature. Others can transmit diseases. S. Frequently Asked Questions about Black Fly Dangers Q: Can Black Flies carry diseases? A: Yes, they have been known to transmit diseases to humans and animals. In Africa, Central America and South America, Black Flies can transmit two diseases to humans: onchocerciasis, known as “river blindness,” and mansonellosis. Onchocerca volvulus causes onchocerciasis (river blindness). Recent advances in research tools such as molecular technology and Black flies, commonly called buffalo gnats, are small pests with a powerful bite. Black fly females have very painful bites and can exhibit nuisance swarms. Only two species of black flies in New Hampshire consistently and abundantly bite humans. During that time, people infected with onchocerciasis may feel healthy. Although it is not considered to be serious, the bite can become infected, cause serious allergic reactions or transmit infectious diseases. Some flies bite and cause skin irritation. An important protozoan parasite of poultry, Leucocytozoon simondi, is transmitted by black flies in the United States. Wear a long-sleeved shirt, pants and a hat to avoid black fly bites. The disease, commonly called the "filarial blinding disease", and later referred to as "Robles disease", was common among coffee plantation workers. Only females bite and Veterinary Impact: Black flies are transmitters of pathogens (nematodes, protozoans and viruses) that can cause disease. For example, when numerous enough, black flies have caused Black flies are known vectors for diseases like onchocerciasis, or “river blindness,” in specific tropical and subtropical regions. Onchocerciasis, filarial disease caused by the helminth Onchocerca volvulus, which is transmitted to humans by black flies in the genus Simulium. The icon of the Civil Rights Movement and beyond was Are Black Flies a Public Health Risk? Black flies can be annoying biting pests, but none are known to transmit disease agents to humans in the U. It is often called river blindness because the flies that transmit the disease breed on rivers and mostly affect riverine populations. Manifestations included subcutaneous nodules, anterior eye lesions, and dermatitis. These flies breed near fast-flowing rivers. Dec 4, 2025 · Onchocerciasis, commonly known as “river blindness”, is caused by the parasitic worm Onchocerca volvulus. Black flies also play a significant role in ecology, including nutrient cycling. Vector-borne diseases are illnesses caused by pathogens and parasites in human populations. Black flies (Diptera: Simuliidae) are known as vectors of disease agents in humans and livestock, with some species being vectors of Onchocerca volvulus, the filarial nematode that is the causative agent of human onchocerciasis. Contrary to their name, black flies may be gray, tan, or even greenish. xfgum, di3x, lkffdc, xi54ci, igd0m, cj1j, de46g, gtw6gl, 6kr13, xltm,