|
Onchocerciasis
Onchocerciasis, also known as river blindness, is a disease caused by infection with the parasitic worm ''Onchocerca volvulus''. Symptoms include severe itching, bumps under the skin, and blindness. It is the second-most common cause of blindness due to infection, after trachoma. The parasitic worm is spread by the bites of a black fly of the ''Simulium'' genus. Usually, many bites are required before infection occurs. These flies live near rivers, hence the common name of the disease, River blindness. Once inside a person, the worms create larvae that make their way out to the skin, where they can infect the next black fly that bites the person. There are a number of ways to make the diagnosis, including placing a biopsy of the skin in normal saline and watching for the larva to come out, looking in the eye for larvae, and looking within the bumps under the skin for adult worms. A vaccine against the disease does not exist. Prevention is by avoiding being bitten by flies. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neglected Tropical Disease
Neglected tropical diseases (NTDs) are a diverse group of tropical infections that are common in low-income populations in developing regions of Africa, Asia, and the Americas. They are caused by a variety of pathogens, such as viruses, bacteria, protozoa, and parasitic worms (helminths). These diseases are contrasted with the "big three" infectious diseases (HIV/AIDS, tuberculosis, and malaria), which generally receive greater treatment and research funding. In sub-Saharan Africa, disease burden, the effect of neglected tropical diseases as a group is comparable to that of malaria and tuberculosis. NTD co-infection can also make HIV/AIDS and tuberculosis more deadly. Some treatments for NTDs are relatively inexpensive. For example, praziquantel for schistosomiasis costs about US $0.20 per child per year. Nevertheless, in 2010 it was estimated that control of neglected diseases would require funding of between US$2 billion and $3 billion over the subsequent five to sev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Onchocerca Volvulus
''Onchocerca volvulus'' is a filarial (arthropod-borne) nematode (roundworm) that causes onchocerciasis (river blindness), and is the second-leading cause of blindness due to infection worldwide after trachoma. It is one of the 20 neglected tropical diseases listed by the World Health Organization, with elimination from certain countries expected by 2025. John O'Neill, an Irish surgeon, first described ''Onchocerca volvulus'' in 1874, when he found it to be the causative agent of 'craw-craw', a skin disease found in West Africa. A Guatemalan doctor, Rodolfo Robles, first linked it to visual impairment in 1917. ''Onchocerca volvulus'' is primarily found in sub-Saharan Africa, and there is also disease transmission in some South American nations, as well as Yemen (see global map bottom right). It is spread from person to person via female biting blackflies of the genus ''Simulium'', and humans are the only known definitive host. Morphology ''Onchocerca volvulus'' parasites ob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ivermectin
Ivermectin is an antiparasitic drug. After its discovery in 1975, its first uses were in veterinary medicine to prevent and treat heartworm and acariasis. Approved for human use in 1987, it is used to treat infestations including head lice, scabies, river blindness (onchocerciasis), strongyloidiasis, trichuriasis, ascariasis and lymphatic filariasis. It works through many mechanisms to kill the targeted parasites, and can be taken by mouth, or applied to the skin for external infestations. It belongs to the avermectin family of medications. William Campbell and Satoshi Ōmura were awarded the 2015 Nobel Prize in Physiology or Medicine for its discovery and applications. It is on the World Health Organization's List of Essential Medicines, and is approved by the US Food and Drug Administration (FDA) as an antiparasitic agent. In 2022, it was the 314th most commonly prescribed medication in the United States, with more than 200,000 prescriptions. It is available as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blindness
Visual or vision impairment (VI or VIP) is the partial or total inability of visual perception. In the absence of treatment such as corrective eyewear, assistive devices, and medical treatment, visual impairment may cause the individual difficulties with normal daily tasks, including reading and walking. The terms ''low vision'' and ''blindness'' are often used for levels of impairment which are difficult or impossible to correct and significantly impact daily life. In addition to the various permanent conditions, fleeting temporary vision impairment, amaurosis fugax, may occur, and may indicate serious medical problems. The most common causes of visual impairment globally are uncorrected refractive errors (43%), cataracts (33%), and glaucoma (2%). Refractive errors include near-sightedness, far-sightedness, presbyopia, and astigmatism (eye), astigmatism. Cataracts are the most common cause of blindness. Other disorders that may cause visual problems include age-related macular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rodolfo Robles
Rodolfo Robles (January 14, 1878 – November 8, 1939) was a Guatemalan physician and philanthropist. In 1915, he was the first to describe onchocerciasis in Latin America, which was known and widespread on the African continent, with the first description of the adult worms made there in 1890 by Sir Patrick Manson. Robles was the first person to describe the etiology of the disease, correctly attributing it to infection with '' Onchocerca volvulus'' parasites. He discerned the etiology from clinical observations among coffee plantation workers in Guatemala, extracting the parasitic worm from a nodule on a child's face. The disease was later referred to as "Roble's disease" in his honor. In the 1930s, Robles also played a role in establishing the first public health campaigns to address onchocerciasis in the Central Endemic Zone of Guatemala, which involved sending teams to endemic areas to provide surgical services and perform nodulectomies. Biography Rodolfo Robles was born ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sub-Saharan Africa
Sub-Saharan Africa is the area and regions of the continent of Africa that lie south of the Sahara. These include Central Africa, East Africa, Southern Africa, and West Africa. Geopolitically, in addition to the list of sovereign states and dependent territories in Africa, African countries and territories that are situated fully in that specified region, the term may also include polities that only have part of their territory located in that region, per the definition of the United Nations geoscheme for Africa, United Nations (UN). This is considered a non-standardised geographical region with the number of countries included varying from 46 to 48 depending on the organisation describing the region (e.g. United Nations, UN, World Health Organization, WHO, World Bank, etc.). The Regions of the African Union, African Union (AU) uses a different regional breakdown, recognising all 55 member states on the continent—grouping them into five distinct and standard regions. The te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Simulium Yahense
''Simulium yahense'' is a species of black flies found in West African rain forests. Their larval stages are found in "smaller, more shaded, cooler breeding waters." One particular group, now eradicated, was found only on the island of Bioko, and was an extremely effective vector for the parasitic worm ''Onchocerca volvulus'' that causes onchocerciasis Onchocerciasis, also known as river blindness, is a disease caused by infection with the parasitic worm ''Onchocerca volvulus''. Symptoms include severe itching, bumps under the skin, and blindness. It is the second-most common cause of blindne ..., or "river blindness". References yahense Insect vectors of human pathogens {{Chironomoidea-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World Health Organization
The World Health Organization (WHO) is a list of specialized agencies of the United Nations, specialized agency of the United Nations which coordinates responses to international public health issues and emergencies. It is headquartered in Geneva, Switzerland, and has 6 regional offices and 150 field offices worldwide. Only sovereign states are eligible to join, and it is the largest intergovernmental health organization at the international level. The WHO's purpose is to achieve the highest possible level of health for all the world's people, defining health as "a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity." The main functions of the World Health Organization include promoting the control of epidemic and endemic diseases; providing and improving the teaching and training in public health, the medical treatment of disease, and related matters; and promoting the establishment of international standards for biologic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Simulium
''Simulium'' is a genus of Black_fly, black flies, which may transmit diseases such as onchocerciasis (river blindness). It is a large genus with almost 2,000 species and 38 subgenus, subgenera. The flies are pool feeders. Their saliva, which contains anticoagulants, a number of enzymes and histamine, is mixed with the blood, preventing clotting until it is ingested by the fly. These bites cause localized tissue damage, and if the number of feeding flies is sufficient, their feeding may produce a blood-loss anaemia. The host's reaction to fly attacks may include systemic illness, allergic reactions or even death, presumably mediated by histamine. In humans, this systemic reaction is known as "black fly fever" and is characterized by headaches, fever, nausea, adenitis, generalized dermatitis, and allergic asthma. Systematics Subgenera: * ''Afrosimulium'' Roger Ward Crosskey, Crosskey, 1969 * ''Anasolen'' Günther Enderlein, Enderlein, 1930 * ''Asiosimulium'' Takaoka & Choo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasitic Worm
Parasitic worms, also known as helminths, are a polyphyletic group of large macroparasites; adults can generally be seen with the naked eye. Many are intestinal worms that are soil-transmitted and infect the gastrointestinal tract. Other parasitic worms such as schistosomes reside in blood vessels. Some parasitic worms, including leeches and monogeneans, are ectoparasites thus, they are not classified as helminths, which are endoparasites. Parasitic worms live in and feed in living hosts. They receive nourishment and protection while disrupting their hosts' ability to absorb nutrients. This can cause weakness and disease in the host, and poses a global health and economic problem. Parasitic worms cannot reproduce entirely within their host's body; they have a life cycle that includes some stages that need to take place outside of the host. Helminths are able to survive in their mammalian hosts for many years due to their ability to manipulate the host's immune respon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Doxycycline
Doxycycline is a Broad-spectrum antibiotic, broad-spectrum antibiotic of the Tetracycline antibiotics, tetracycline class used in the treatment of infections caused by bacteria and certain parasites. It is used to treat pneumonia, bacterial pneumonia, acne vulgaris, acne, chlamydia infections, Lyme disease, cholera, typhus, and syphilis. It is also used to prevent malaria. Doxycycline may be taken Oral administration, by mouth or by intravenous, injection into a vein. Common side effects include diarrhea, nausea, vomiting, abdominal pain, and an increased risk of sunburn. Use during pregnancy is not recommended. Like other agents of the tetracycline class, it either slows or kills bacteria by inhibiting protein production. It kills malaria by targeting a plastid organelle, the apicoplast. Doxycycline was patented in 1957 and came into commercial use in 1967. It is on the WHO Model List of Essential Medicines, World Health Organization's List of Essential Medicines. Doxycyc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
