Desertification is a type of land degradation in drylands in which biological productivity is lost due to natural processes or induced by human activities whereby fertile areas become arid. It is the spread of arid areas caused by a variety of factors, such as overexploitation of soil as a result of human activity and the effects of climate change. Geographic areas most affected include the Sahel region in Africa, the Gobi Desert and Mongolia in Asia as well as parts of South America. Drylands occupy approximately 40–41% of Earth's land area and are home to more than 2 billion people.
African trypanosomiasis, also known as African sleeping sickness or simply sleeping sickness, is an insect-borne parasitic infection of humans and other animals. It is caused by the species Trypanosoma brucei. Humans are infected by two types, Trypanosoma brucei gambiense (TbG) and Trypanosoma brucei rhodesiense (TbR). TbG causes over 92% of reported cases. Both are usually transmitted by the bite of an infected tsetse fly and are most common in rural areas.
Tsetse are large, biting flies that inhabit much of tropical Africa. Tsetse flies include all the species in the genus Glossina, which are placed in their own family, Glossinidae. The tsetse is an obligate parasite, which lives by feeding on the blood of vertebrate animals. Tsetse has been extensively studied because of their role in transmitting disease. They have a pronounced economic impact in sub-Saharan Africa as the biological vectors of trypanosomes, causing human and animal trypanosomiasis.
Trypanosomiasis or trypanosomosis is the name of several diseases in vertebrates caused by parasitic protozoan trypanosomes of the genus Trypanosoma. In humans this includes African trypanosomiasis and Chagas disease. A number of other diseases occur in other animals.
The sterile insect technique (SIT) is a method of biological insect control, whereby overwhelming numbers of sterile insects are released into the wild. The released insects are preferably male, as this is more cost-effective and the females may in some situations cause damage by laying eggs in the crop, or, in the case of mosquitoes, taking blood from humans. The sterile males compete with fertile males to mate with the females. Females that mate with a sterile male produce no offspring, thus reducing the next generation's population. Sterile insects are not self-replicating and, therefore, cannot become established in the environment. Repeated release of sterile males over low population densities can further reduce and in cases of isolation eliminate pest populations, although cost-effective control with dense target populations is subjected to population suppression prior to the release of the sterile males.
Trypanosoma brucei is a species of parasitic kinetoplastid belonging to the genus Trypanosoma that is present in sub-Saharan Africa. Unlike other protozoan parasites that normally infect blood and tissue cells, it is exclusively extracellular and inhabits the blood plasma and body fluids. It causes deadly vector-borne diseases: African trypanosomiasis or sleeping sickness in humans, and animal trypanosomiasis or nagana in cattle and horses. It is a species complex grouped into three subspecies: T. b. brucei, T. b. gambiense and T. b. rhodesiense. The first is a parasite of non-human mammals and causes nagana, while the latter two are zoonotic infecting both humans and animals and cause African trypanosomiasis.
Major-General Sir David Bruce was a Scottish pathologist and microbiologist who made some of the key contributions in tropical medicine. In 1887, he discovered a bacterium, now called Brucella, that caused what was known as Malta fever. In 1894, he discovered a protozoan parasite, named Trypanosoma brucei, as the causative pathogen of nagana.
Trypanosoma suis is a species of excavate trypanosome in the genus Trypanosoma that causes one form of the surra disease in animals. It infects pigs. It does not infect humans.
Animal trypanosomiasis, also known as nagana and nagana pest, or sleeping sickness, is a disease of vertebrates. The disease is caused by trypanosomes of several species in the genus Trypanosoma such as T. brucei. T. vivax causes nagana mainly in West Africa, although it has spread to South America. The trypanosomes infect the blood of the vertebrate host, causing fever, weakness, and lethargy, which lead to weight loss and anemia; in some animals the disease is fatal unless treated. The trypanosomes are transmitted by tsetse flies.
Wigglesworthia glossinidia is a species of gram-negative bacteria which was isolated from the gut of the tsetse fly. W. glossinidia is a bacterial endosymbiont of the tsetse fly. Because of this relationship, Wigglesworthia has lost a large part of its genome and has one of the smallest known genomes of any living organism, consisting of a single chromosome of 700,000 bp and a plasmid of 5,200. Together with Buchnera aphidicola, Wigglesworthia has been the subject of genetic research into the minimal genome necessary for any living organism. Wigglesworthia also synthesizes key B-complex vitamins which the tsetse fly does not get from its diet of blood. Without the vitamins Wigglesworthia produces, the tsetse fly has greatly reduced growth and reproduction. Since the tsetse fly is the primary vector of Trypanosoma brucei, the pathogen that causes African trypanosomiasis, it has been suggested that W. glossinidia may one day be used to help control the spread of this disease.
The desert warthog is a species of even-toed ungulate in the pig family (Suidae), found in northern Kenya and Somalia, and possibly Djibouti, Eritrea, and Ethiopia. This is the range of the extant subspecies, commonly known as the Somali warthog. Another subspecies, commonly known as the Cape warthog, became extinct around 1865, but formerly occurred in South Africa.
Ernest Edward Austen DSO was an English entomologist specialising in Diptera and Hymenoptera.
Folonzo is a town in the Niangoloko Department of Comoé Province in south-western Burkina Faso. The town has a population of 1,618.
Charles Francis Massy Swynnerton CMG was an English naturalist noted for his contributions to tsetse fly research.
Émile Roubaud was a French biologist and entomologist known for his work on paludism, yellow fever and sleeping sickness.
Hytrosaviridae is a family of double-stranded DNA viruses that infect insects. The name is derived from Hytrosa, sigla from the Greek Hypertrophia for 'hypertrophy' and 'sialoadenitis' for 'salivary gland inflammation.'
The Desert Locust Control Organization for Eastern Africa (DLCO-EA) is "a regional pest and vector management organization established by an International Convention signed in Addis Ababa, Ethiopia in 1962". The Desert Locust Control Organisation for Eastern Africa (DLCO-EA) is a regional organization for integrated pest and vector management to ensure food security in Eastern Africa.
Glossina fuscipes is a riverine fly species in the genus Glossina, which are commonly known as tsetse flies. Typically found in sub-Saharan Africa but with a small Arabian range, G. fuscipes is a regional vector of African trypanosomiasis, commonly known as sleeping sickness, that causes significant rates of morbidity and mortality among humans and livestock. Consequently, the species is among several being targeted by researchers for population control as a method for controlling the disease.
Glossina morsitans is a species of tsetse fly in the genus Glossina. It is one of the major vectors of Trypanosoma brucei rhodesiense in African savannas.
The Sleeping Sickness Commission was a medical project established by the British Royal Society to investigate the outbreak of African sleeping sickness or African trypanosomiasis in Africa at the turn of the 20th century. The outbreak of the disease started in 1900 in Uganda, which was at the time a protectorate of the British Empire. The initial team in 1902 consisted of Aldo Castellani and George Carmichael Low, both from the London School of Hygiene and Tropical Medicine, and Cuthbert Christy, a medical officer on duty in Bombay, India. From 1903, David Bruce of the Royal Army Medical Corps and David Nunes Nabarro of the University College Hospital took over the leadership. The commission established that species of blood protozoan called Trypanosoma brucei, named after Bruce, was the causative parasite of sleeping sickness.
