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Symptoms begin with fever, headaches, and joint pains. If untreated, the disease slowly overcomes the defences of the infected person, and symptoms spread to anaemia, endocrine problems, and cardiovascular and kidney disorders. The disease then enters a neurological phase when the parasite passes through the blood-brain barrierThe blood-brain barrier is a physical barrier between the blood vessels in the central nervous system, and the central nervous system itself. The barrier stops many substances from travelling across it. The existence of such a barrier was first noticed in. The symptoms of the second phase is what gives the disease its name: besides confusionConfusion can have the following meanings: Unclarity, e. arising from ambiguity. A technical concept in cryptography; see Confusion and diffusion. Mental confusion (such as paranoia) may be caused by drugs or mental illness. It is an imprecise term but ca and reduced coordination, the sleep cycle is disturbed with bouts of lethargy punctuated with manic periods progressing to daytime somnolence and nighttime insomniaFor the novel by Stephen King, see Insomnia (novel). Insomnia is a sleep disorder characterised by an inability to sleep and/or to remain asleep for a reasonable period during the night. Sufferers typically complain of being unable to close their eyes for. Without treatment, the disease is fatal, with progressive mental deterioration leading to coma and death. Damage caused in the neurological phase can be irreversible.
The disease is found in two forms, depending on the parasite, either Trypanosoma brucei gambiense or Trypanosoma brucei rhodesiense . T. b. gambiense is found in central and western AfricaAfrica is the world's second-largest continent in both area and population, after Asia. 30,244,050 km2 (11,677,240 mi2) including the islands, it covers 20. 3% of the total land area on Earth, and with over 800 million human inhabitants it accounts for ar; it causes a chronic conditionIn medicine, a persistent and lasting condition is said to be chronic (from Greek chronos . For example, a chronic illness is one that persists for a long time, usually more than three months. By analogy, this adjective has come to describe problems which that can extend in a passive phase for months or years before symptoms emerge. T. b. rhodesiense is found in southern and eastern Africa; its infection emerges in a few weeks and is more virulent and faster developing.
The primary condition is treated with either suramin (T. b. rhodesiense/gambiense) or pentamidine (T. b. gambiense). Advanced cases can be treated with melarsoprol or eflornithine . All these drugs, especially melarsoprol, have many undesirable side-effects, and the treatment regimen is often difficult to enforce.
The condition has been present in Africa from at least the 14th century. The causative agent and the vector were not identified until 1902 - 1903, and the differentiation between protozoa was not made until 1910. An arsenic based drug, atoxyl , was the first effective drug, developed by Paul Ehrlich and Kiyoshi Shiga in 1906. After patients became blind due to incorrect dosages of atoxyl, the organo-arsenical melarsoprol (Arsobal) was developed in the 1940s. It was effective, but 3 - 10% of those injected had reactive encephalopathy (convulsions, progressive coma, or psychotic reactions), and 10 - 70% died; it could cause brain damage in those that survived the encephalopathy. Treatment of the primary condition began in the 1920s with suramin. Eflornithine (difluoromethylornithine or DFMO), the most modern treatment, was developed in the 1970s by Albert Sjoerdsmanot and underwent clinical trials in the 1980s. The drug was approved by the FDA in 1990, but Aventis, the company responsible for its manufacture, halted production in 1999. Patients with sleeping sickness are currently treated with melarsoprol.
Instances of Sleeping sickness are being reduced by the use of the Sterile Atomic Fly.
See also:
Infectious diseases Sleep disorders