Trypanosomiasis, African (Sleeping Sickness) - Chapter 3 - 2016 Yellow Book | Travelers' Health | CDC Trypanosomiasis, African (Sleeping Sickness) Two subspecies of the protozoan parasite Trypanosoma brucei (T. b. rhodesiense and T. b. gambiense). TRANSMISSION The bite of an infected tsetse fly (Glossina spp.). Bloodborne and congenital transmission are rare. EPIDEMIOLOGY Endemic in rural sub-Saharan Africa. T. b. rhodesiense is found in eastern and southeastern Africa, mainly Tanzania, Uganda, Malawi, Zambia, and Zimbabwe. T. b. gambiense is found in central Africa and in limited areas of West Africa, primarily in Democratic Republic of the Congo, Angola, Sudan, Central African Republic, Guinea, Republic of the Congo, Chad, and northern Uganda. In 2012, 7,197 sleeping sickness cases were reported to the World Health Organization; T. b. gambiense accounted for >98% of cases.

Tsetse flies inhabit rural, densely vegetated areas; people who only travel to urban areas are not at risk. Flies bite during the day, and <1% are infected. Risk of infection increases with the number of fly bites, which is not always directly correlated with duration of travel. CLINICAL PRESENTATION T. b. rhodesiense Symptoms generally appear within 1–3 weeks of the infective bite and may include high fever, a chancre at the bite site, skin rash, headache, myalgia, thrombocytopenia, and less commonly, splenomegaly, renal failure, or cardiac dysfunction. Central nervous system involvement can occur within a month of infection and results in mental deterioration and eventually, death. T. b. gambiense Nonspecific but may include fever, headache, malaise, myalgia, facial edema, pruritus, lymphadenopathy, and weight loss. Central nervous system involvement occurs after months to years of infection and is characterized by somnolence, severe headache, and a range of neurologic manifestations, including mood disorders, behavior change, focal deficits, and endocrine disorders. The clinical course of disease caused by T. b.

gambiense is generally less severe than that caused by T. b. rhodesiense, but both are fatal if not treated. DIAGNOSIS Bites are characteristically painful, and a chancre may develop at the bite location. Identification of parasites in specimens of blood, chancre fluid or tissue, lymph node aspirate, or cerebrospinal fluid. Buffy-coat preparations concentrate the parasite, enabling easier visualization for diagnosis. Diagnostic assistance is available through CDC ( ; 404-718-4745; parasites@cdc.gov). TREATMENT Infection can usually be cured by a course of antitrypanosomal therapy, although long-term sequelae, including permanent damage to the central nervous system, may remain. Treatment drugs (suramin, melarsoprol, eflornithine) are provided by CDC under investigational protocols. Clinicians can consult with CDC for assistance with treatment. PREVENTION Avoid tsetse fly bites. Travelers should wear clothing of wrist and ankle length made of medium-weight fabric in neutral colors, as tsetse flies are attracted to bright or dark colors and can bite through lightweight clothing.

Permethrin-impregnated clothing and use of DEET repellent may reduce the number of fly bites. CDC website: BIBLIOGRAPHY Brun R, Blum J, Chappuis F, Burri C. Human African trypanosomiasis. Lancet. 2010 Jan 9;375(9709): 148–59. Simarro PP, Franco JR, Cecchi G, Paone M, Diarra A, Ruiz Postigo JA, et al. Human African trypanosomiasis in non-endemic countries (2000–2010). J Travel Med. 2012 Jan–Feb; 19(1):44–53. Trypanosomiasis - catch, body, contagious, causes, What Is Trypanosomiasis? Trypanosomiasis Trypanosomiasis Trypanosomiasis (trih-pan-o-so-MY-uh-sis) is a disease found in Africa and the American continents that is caused by infection with a parasite.

Forms of the disease may persist for many years and have several phases, with symptoms that can vary from one stage to the next. KEYWORDS for searching the Internet and other reference sources Chagas disease Tsetse fly What Is Trypanosomiasis? Trypanosomiasis refers to three types of infections caused by protozoa * and spread to humans through insect bites. There are two kinds of African trypanosomiasis, East African and West African. Both of these varieties also are known as sleeping sickness. The disease can affect people living on the African continent south of the Sahara Desert. American trypanosomiasis also is called Chagas (SHAH-gus) disease. It occurs only on the American continents, from Mexico to Argentina. What Causes Trypanosomiasis? The bite of an infected tsetse (SET-see) fly usually transmits the organisms that cause the African forms of trypanosomiasis. These flies live in the countryside in Africa, especially in bushes and thick vegetation near rivers and lakes.

Tsetse flies infected with the protozoan Trypanosoma brucei rhodesiense (trih-pan-o-SO-mah BRU-see-eye ro-dee-see-EN-see) spread East African trypanosomiasis, the most severe form of the disease, to humans. The West African variety comes from a fly infected with Trypanosoma brucei gambiense (trih-pan-o-SO-mah BRU-see-eye gam-be-EN-see). * protozoa (pro-tuh-ZOH-uh) are single-celled microorganisms (tiny organisms), some of which are capable of causing disease in humans. * feces (FEE-seez) is the excreted waste from the gastrointestinal tract. Reduviid (rih-DO-vee-id) bugs (also called assassin, cone-nose, or kissing bugs) carry the Trypanosoma cruzi (trih-pan-o-SO-mah KROO-zee) protozoa that cause the American variety of trypanosomiasis, or Chagas disease, named for the Brazilian doctor who discovered it.

These bugs hide during the day in the cracks in mud and adobe homes. At night they crawl across sleeping people and bite them, usually on the face but sometimes on the arms, legs, or trunk. They also leave behind their feces * , which contain the protozoa. Without knowing it, people can rub The tsetse fly is responsible for spreading trypanosomiasis in Africa. ©Rob and Ann Simpson/Visuals Unlimited, Inc. the infected feces into the bite, a cut or open sore, or even into their noses, mouths, or eyes. How Common Is Trypanosomiasis? Trypanosomiasis can infect people of every age and race, though it is uncommon in the United States. Since the late 1960s, fewer than 30 cases have been reported among U.S. citizens traveling to areas where the infection is found. In other parts of the world, however, the disease affects thousands of people. The World Health Organization estimates that as many as 500,000 people could have African trypanosomiasis, but because of poor monitoring most of these cases are not reported.

Between 16 million and 18 million people in the Americas currently have Chagas disease. Approximately 50,000 may die from the disease each year. Is Trypanosomiasis Contagious? People cannot catch any form of trypanosomiasis in the same way that they catch a cold or the flu from other people. Only the tsetse fly spreads the African varieties, and the reduviid bug spreads Chagas disease. Rarely, a mother infected with the West African variety of trypanosomiasis or with Chagas disease can pass the illness to her unborn child. People who receive a transfusion * of blood or an organ transplant from an infected person also may contract the disease; this form of transmission tends to happen more often with Chagas disease than with the African types. What Are the Symptoms of the Disease? African trypanosomiasis People who contract the African varieties of trypanosomiasis may start sleeping more, though this usually does not happen until the later stages of the disease. Sleeping sickness may start with the appearance of a sore called a chancre (SHANG-ker) at the spot where the person received the tsetse fly bite.

Later symptoms include fever, extreme tiredness, severe headaches, rashes, itching, joint pain, and swelling of the hands and feet. The lymph nodes * on the back of the neck may become swollen as well. These signs typically appear 2 to 4 weeks after infection with East African trypanosomiasis. * transfusion (trans-FYOO-zhun) is a procedure in which blood or certain parts of blood, such as specific cells, is given to a person who needs it because of illness or blood loss. * lymph (LIMF) nodes are small, bean-shaped masses of tissue that contain immune system cells that fight harmful microorganisms. Lymph nodes may swell during infections. * blood-brain barrier is a biological shield in the body that helps prevent germs or other potentially harmful materials in the blood from entering the brain and spinal cord. * seizures (SEE-zhurs) are sudden bursts of disorganized electrical activity that interrupt the normal functioning of the brain, often leading to uncontrolled movements in the body and sometimes a temporary change in consciousness, * chronic (KRAH-nik) means continuing for a long period of time.

* antibodies (AN-tih-bah-deez) are protein molecules produced by the body's immune system to help fight specific infections caused by microorganisms, such as bacteria and viruses. Other symptoms can follow quickly, as the protozoa cross the blood-brain barrier * and start affecting a patient's mental functions. The later stages of sleeping sickness may bring mental confusion, changes in personality, problems with walking and talking, weight loss, and seizures * . The spleen and liver may become enlarged. Sleeping sickness gets its name from the later part of the disease, when the sick person has nighttime insomnia (in-SOM-nee-uh, an inability to sleep) but sleeps for long periods during the day. If the person does not receive treatment, the heart muscles may become inflamed or weakened, causing death from heart failure. The early symptoms in West African trypanosomiasis are similar but may take longer to appear. Months or years may pass before an infected person becomes sick, and the disease develops more slowly, though it still can cause death if it is left untreated. The gap between infection and the start of symptoms can make this form of sleeping sickness difficult to diagnose.

Chagas disease The first sign of Chagas disease may show up a few hours after infection, when a raised red spot called a chagoma (chuh-GO-mah) appears at the site of the insect bite. Most people have no other symptoms during the early, or acute, phase of the disease, which begins a few weeks later. People who experience symptoms may have fevers, rashes, extreme tiredness, vomiting, loss of appetite, or swollen lymph nodes. The side of the face where the infected feces were rubbed into an eye or a bug bite may swell. In most people these symptoms usually disappear within 4 to 8 weeks without causing problems, but infants can die in this early stage from brain swelling. About 10 to 20 years after this first phase, approximately one-third of infected people can show symptoms of the chronic * phase of Chagas disease. They may become constipated and experience trouble swallowing. The heart may become enlarged, and patients may have altered heart rhythms or heart failure leading to death. How Do Doctors Diagnose Trypanosomiasis?

Because all types of trypanosomiasis are rare in the United States, it is important for people who have any symptoms of the disease to let their doctor know right away if they have been traveling in areas where the disease is common. To diagnose sleeping sickness or Chagas disease, a doctor will order blood tests to look for protozoa or antibodies * to the organism. In cases where the doctor suspects sleeping sickness, a sample drawn from fluid surrounding the brain and spinal cord or tissue from swollen lymph nodes may be examined for evidence of the disease. If a patient has a suspicious-looking skin lesion * , a biopsy * will be performed to test for Trypanosoma cruzi protozoa. Can Trypanosomiasis Be Treated Successfully? There are medications available to treat all types of the disease. Doctors recommend that people with trypanosomiasis receive treatment as soon as possible. Treatment is given in a hospital. After leaving the hospital, patients typically are watched closely by a doctor for at least 2 years, to see whether they show any signs that they still have the infection.

Global Warming The bite of an insect can transmit bacteria, protozoa, or even worms into a person's bloodstream, leading to a variety of illnesses. Trypanosomiasis is just one example of a tropical insect-borne disease. Here are a few others, along with the insects that spread them: ■ Malaria or river blindness black flies Why are these diseases common to the tropics? It is because the hot and often rainy climate makes the tropics an ideal breeding ground for insects. Greenpeace, among other organizations dedicated to protecting the environment, has warned that global warming could create new breeding grounds for insects throughout the world. At the same time, rising temperatures could raise insect reproductive rates, increasing their numbers. As the climate in the United States and Europe becomes more "tropical," diseases such as yellow fever and malaria may become more common, bringing the tropics into our own backyards. * lesion (LEE-zhun) is a general term referring to a sore or a damaged or irregular area of tissue. * biopsy (BI-op-see) is a test in which a small sample of skin or other body tissue is removed and examined for signs of disease. What Happens to People with Trypanosomiasis?

East African sleeping sickness can move through the body quickly, progressing in just weeks or months to the most serious phase of illness. West African sleeping sickness takes longer to develop. People may not A microscopic view of blood infected with the protozoa that cause, trypanosomiasis. These symptoms cause a disease known as sleeping sickness in Africa and Chagas disease in Latin America. Custom Medical Stock Photo, Inc. reach the critical phase for months or even years. People who do not receive treatment for African trypanosomiasis can die from heart failure, and those who wait to start treatment may have permanent brain damage. Long-term complications of Chagas disease, which may not appear for 20 or more years after infection, include damage to the digestive and nervous systems, heart problems, and sudden death. Can Trypanosomiasis Be Prevented? There is no vaccine or medication that can prevent any form of the disease, so it is wise for people who travel in areas where the disease is common to take precautions. In Africa this includes wearing clothes of thick material, with long sleeves and long pants. Neutral colors, such as tan, are best because tsetse flies are attracted to dark and bright colors.

Doctors recommend that travelers to Africa sleep under netting and avoid riding in the backs of open trucks, because dust from moving vehicles attracts the flies. It is also advisable to not walk through brush. In areas where Chagas disease is found, it is a good idea for people to avoid sleeping in mud, adobe, or thatch houses; to sleep under netting; and to use insect repellent. See also African Trypanosomiasis African Trypanosomiasis For more information: What is African trypanosomiasis? There are two types of African trypanosomiasis (also called sleeping sickness); each is named for the region of Africa in which they are found. The disease is caused by a parasite named Trypanosoma brucei rhodesiense (tri-PAN-o-SO-ma BREW-see- eye rho-DEE-see-ense), carried by the tsetse fly.Worldwide, approximately 25,000 new cases of both East and West African trypanosomiasis are reported to the World Health Organization each year. However, many cases are not reported due to a lack of infrastructure and the true number of new cases is undoubtedly much higher.

Since 1967, thirty-six cases of East African trypanosomiasis have been reported within the United States, all among individuals who had traveled to Africa. How is African trypanosomiasis spread? An individual will get East African trypanosomiasis if they are bitten by a tsetse fly infected with the Trypanosoma brucei rhodesiense parasite. The tsetse fly is common only to Africa. An individual gets West African trypanosomiasis through the bite of an infected tsetse fly, found only in Africa. On rare occasions, a pregnant woman may pass the infection to her baby, or an individual may become infected through a blood transfusion or organ transplant . Is African trypanosomiasis a serious illness? Yes. If a person fails to receive medical treatment for East African trypanosomiasis, death will occur within several weeks to months. West African trypanosomiasis is fatal if it is not treated. Where can you become infected with African trypanosomiasis?

East African trypanosomiasis is found in parts of Eastern and Central Africa, including Uganda, Kenya, Tanzania, Malawi, Ethiopia, Zaire, Zimbabwe, and Botswana. Areas where infection is spread are largely determined by the location of the infected tsetse fly and wild animal population. West African trypanosomiasis can be contracted in parts of Western and Central Africa. The tsetse fly lives only in Africa; areas where infection is spread are largely determined by where the infected tsetse fly is found. What are the symptoms of African trypanosomiasis? East Aftrican trypanosomiasis: A bite by the tsetse fly is often painful and can develop into a red sore, also called a chancre (SHAN-ker). Fever, severe headaches , irritability, extreme fatigue , swollen lymph nodes , and aching muscles and joints are common symptoms of sleeping sickness. Some people develop a skin rash . Progressive confusion, personality changes, slurred speech, seizures , and difficulty in walking and talking occur when infection has invaded the central nervous system . If left untreated, infection becomes worse and death will occur within several weeks or months.

West African trypanosomiasis: A bite by the tsetse fly is often painful. Occasionally, within 1 to 2 weeks, the infective bite develops into a red sore, also called a chancre (SHAN-ker). Several weeks to months later, other symptoms of sleeping sickness occur. These include fever, rash , swelling around the eye and hands, severe headaches , extreme fatigue , aching muscles and joints. You may develop swollen lymph nodes on the back of your neck called Winterbottom's sign. Weight loss occurs as the illness progresses. Progressive confusion, personality changes, slurred speech, irritability, loss of concentration, seizures, and difficulty in walking and talking occurs when infection has invaded the central nervous system. These symptoms become worse as the illness progresses. Sleeping for long periods of the day and having insomnia at night is a common symptom. If left untreated, infection becomes worse and death will occur within several months to years after infection. Continued How soon after infection will I have symptoms of African trypanosomiasis? With East African trypanosomiasis, symptoms begin within 1 to 4 weeks of getting an infected tsetse fly bite.

With West African trypanosomiasis, symptoms occur within months to years after getting an infected tsetse fly bite. What should I do if I think I may have African trypanosomiasis? If you suspect that you may have East African trypanosomiasis, immediately consult with your health care provider who will order several tests to look for the parasite. Common tests include blood samples, a spinal tap , and skin biopsies , especially if you have a chancre. If you suspect that you may have West African trypanosomiasis, see your health care provider who will order several tests to look for the parasite. Common tests include blood samples and a spinal tap. Your physician may also take a sample of fluid from swollen lymph nodes. What is the treatment for African trypanosomiasis? Medical treatment of East African trypanosomiasis should begin as soon as possible and is based on the infected person’s symptoms and laboratory results. Medication for the treatment of East African trypanosomiasis is available through the CDC. Hospitalization for treatment is necessary. Periodic follow-up exams that include a spinal tap are required for 2 years.

Medication for the treatment of West African trypanosomiasis is available. Hospitalized treatment of West African trypanosomiasis should begin as soon as possible and is based on the infected person’s symptoms and laboratory results. Hospitalization for treatment is necessary. Periodic follow-up exams that include a spinal tap are required for 2 years. Once infected, am I immune to African trypanosomiasis? No one is immune from East African trypanosomiasis. Even if you had the disease once, you can get re-infected. Who is at risk for contracting African trypanosomiasis? East African trypanosomiasis is usually found in woodland and savannah areas away from human habitation. Tourists, hunters, game wardens, and other persons working or visiting game parks in East and Central Africa are at greatest risk for illness. Tsetse flies can be found in Western and Central African forests, in areas of thick shrubbery and trees by rivers and waterholes. Risk of infection increases with the number of times a person is bitten by the tsetse fly.

Therefore, tourists are not at great risk for contracting West African trypanosomiasis unless they are traveling and spending long periods of time in rural areas of Western and Central Africa. Continued Can I take a medication to prevent African trypanosomiasis? There is neither a vaccine nor recommended drug available to prevent East or West African trypanosomiasis. How can I prevent African trypanosomiasis and prevent other insect bites? Wear protective clothing, including long-sleeved shirts and pants. The tsetse fly can bite through thin fabrics, so clothing should be made of thick material. Wear khaki or olive colored clothing. The tsetse fly is attracted to bright colors and very dark colors. Use insect repellant. Though insect repellants have not proven effective in preventing tsetse fly bites, they are effective in preventing other insects from biting and causing illness. Use bed netting when sleeping. Inspect vehicles for tsetse flies before entering. Do not ride in the back of jeeps, pickup trucks or other open vehicles. The tsetse fly is attracted to the dust that moving vehicles and wild animals create. Avoid bushes. The tsetse fly is less active during the hottest period of the day.

It rests in bushes but will bite if disturbed. For more information: McGovern TW, William W, Fitzpatrick JE , et al. Cutaneous manifestations of African trypanosomiasis. Arch Dermatol 1995;131:1178-82. Bryan R, Waskin J, Richards F, et al. African trypanosomiasis in American travelers: a 20-year review. Travel Medicine. Steffen R, Lobel HO, Haworth J, Bradley DJ, eds. Berlin: Springer-Verlag, 1989:384-8. See also American trypanosomiasis (also known as chagas disease ). This fact sheet is for information only and is not meant to be used for self-diagnosis or as a substitute for consultation with a health care provider. If you have any questions about the disease described above or think that you may have a parasitic infection, consult a health care provider.

WebMD Public Information from the CDC Pagination WHO | Trypanosomiasis, human African (sleeping sickness) Trypanosomiasis, human African (sleeping sickness) Updated February 2016 Key facts Sleeping sickness occurs in 36 sub-Saharan Africa countries where there are tsetse flies that transmit the disease. The people most exposed to the tsetse fly and therefore the disease live in rural areas and depend on agriculture, fishing, animal husbandry or hunting. Human African trypanosomiasis takes 2 forms, depending on the parasite involved: Trypanosoma brucei gambiense accounts for more than 98% of reported cases. Sustained control efforts have reduced the number of new cases. In 2009 the number reported dropped below 10 000 for the first time in 50 years, and in 2014 there were 3796 cases recorded. Diagnosis and treatment of the disease is complex and requires specifically skilled staff. Definition of the disease Human African trypanosomiasis, also known as sleeping sickness, is a vector-borne parasitic disease.

It is caused by infection with protozoan parasites belonging to the genus Trypanosoma. They are transmitted to humans by tsetse fly (Glossina genus) bites which have acquired their infection from human beings or from animals harbouring human pathogenic parasites. Tsetse flies are found just in sub-Saharan Africa though only certain species transmit the disease. For reasons that are so far unexplained, in many regions where tsetse flies are found, sleeping sickness is not. Rural populations living in regions where transmission occurs and which depend on agriculture, fishing, animal husbandry or hunting are the most exposed to the tsetse fly and therefore to the disease. The disease develops in areas ranging from a single village to an entire region. Within an infected area, the intensity of the disease can vary from one village to the next. Forms of human African trypanosomiasis Human African trypanosomiasis takes 2 forms, depending on the parasite involved: Trypanosoma brucei gambiense is found in 24 countries in west and central Africa. This form currently accounts for over 98% of reported cases of sleeping sickness and causes a chronic infection.

A person can be infected for months or even years without major signs or symptoms of the disease. When more evident symptoms emerge, the patient is often already in an advanced disease stage where the central nervous system is affected. Trypanosoma brucei rhodesiense is found in 13 countries in eastern and southern Africa. Nowadays, this form represents under 2% of reported cases and causes an acute infection. First signs and symptoms are observed a few months or weeks after infection. The disease develops rapidly and invades the central nervous system. Only Uganda presents both forms of the disease, but in separate zones. Another form of trypanosomiasis occurs mainly in Latin America. It is known as American trypanosomiasis or Chagas disease. The causal organism belongs to a different Trypanosoma subgenus and is transmitted by a different vector. Animal trypanosomiasis Other parasite species and sub-species of the Trypanosoma genus are pathogenic to animals and cause animal trypanosomiasis in wild and domestic animals. In cattle the disease is called Nagana. Trypanosomiasis in domestic animals, particularly in cattle, is a major obstacle to the economic development of affected rural areas.

Animals can host the human pathogen parasites, especially T.b. rhodesiense, of which domestic and wild animals are an important reservoir. Animals can also be infected with T.b. gambiense and act as a reservoir to a lesser extent. However the precise epidemiological role of the animal reservoir in the gambiense form of the disease is not yet well known. Major human epidemics There have been several epidemics in Africa over the last century: one between 1896 and 1906, mostly in Uganda and the Congo Basin; one in 1920 in a number of African countries; and the most recent epidemic started in 1970 and lasted until the late 1990s. The 1920 epidemic was controlled thanks to mobile teams which carried out the screening of millions of people at risk. By the mid-1960s, the disease was under control with less than 5000 cases reported in the whole continent. After this success, surveillance was relaxed, and the disease reappeared, reaching epidemic proportions in several regions by 1970.

The efforts of WHO, national control programmes, bilateral cooperation and nongovernmental organizations (NGOs) during the 1990s and early 21st century reversed the curve. Since the number of new human African trypanosomiasis cases reported between 2000 and 2012 dropped by 73%, the WHO neglected tropical diseases roadmap targeted its elimination as a public health problem by 2020. Disease burden Sleeping sickness threatens millions of people in 36 countries in sub-Saharan Africa. Many of the affected populations live in remote rural areas with limited access to adequate health services, which complicates the surveillance and therefore the diagnosis and treatment of cases. In addition, displacement of populations, war and poverty are important factors that facilitate transmission. In 1998, almost 40 000 cases were reported, but estimates were that 300 000 cases were undiagnosed and therefore untreated. During the most recent epidemic the prevalence reached 50% in several villages in Angola, the Democratic Republic of the Congo, and South Sudan. Sleeping sickness was the first or second greatest cause of mortality in those communities, even ahead of HIV/AIDS.

In 2009, after continued control efforts, the number of cases reported dropped below 10 000 (9878) for the first time in 50 years. This decline in number of cases has continued with 3796 new cases reported in 2014, the lowest level since the start of systematic global data-collection 75 years ago. The estimated number of actual cases is below 20 000 and the estimated population at risk is 65 million people. Current disease distribution The disease incidence differs from one country to another as well as in different parts of a single country. In the last 10 years, over 70% of reported cases occurred in the Democratic Republic of the Congo (DRC). The DRC is the only country that currently reports more than 1000 new cases annually and accounts for 85% of the cases reported in 2014. Central African Republic is the only country that declared between 100 and 200 new cases in 2014.

Countries such as Angola, Burkina Faso, Cameroon, Chad, Congo, Côte d'Ivoire, Gabon, Guinea, Malawi, South Sudan, Uganda, United Republic of Tanzania, Zambia and Zimbabwe are reporting fewer than 100 new cases per year. Countries like Benin, Botswana, Burundi, Equatorial Guinea, Ethiopia, Gambia, Ghana, Guinea Bissau, Kenya, Liberia, Mali, Mozambique, Namibia, Niger, Nigeria, Rwanda, Senegal, Sierra Leone, Swaziland and Togo have not reported any new cases for over a decade. Transmission of the disease seems to have stopped in some of these countries but there are still some areas where it is difficult to assess the exact situation because the unstable social circumstances and/or difficult accessibility hinder surveillance and diagnostic activities. Infection and symptoms The disease is mostly transmitted through the bite of an infected tsetse fly but there are other ways in which people are infected: Mother-to-child infection: the trypanosome can cross the placenta and infect the fetus. Mechanical transmission through other blood-sucking insects is possible, however, it is difficult to assess its epidemiological impact. Accidental infections have occurred in laboratories due to pricks with contaminated needles.

Transmission of the parasite through sexual contact has been documented. In the first stage, the trypanosomes multiply in subcutaneous tissues, blood and lymph. This is also called haemo-lymphatic stage, which entails bouts of fever, headaches, joint pains and itching In the second stage the parasites cross the blood-brain barrier to infect the central nervous system. This is known as the neurological or meningo-encephalic stage. In general this is when more obvious signs and symptoms of the disease appear: changes of behaviour, confusion, sensory disturbances and poor coordination. Disturbance of the sleep cycle, which gives the disease its name, is an important feature. Without treatment, sleeping sickness is considered fatal although cases of healthy carriers have been reported. Disease management: diagnosis Disease management is made in 3 steps: Screening for potential infection. This involves using serological tests (only available for T.b.gambiense) and checking for clinical signs - especially swollen cervical lymph nodes. Diagnosing by establishing whether the parasite is present in body fluids. Staging to determine the state of disease progression. This entails examining the cerebrospinal fluid obtained by lumbar puncture.

Diagnosis must be made as early as possible to avoid progressing to the neurological stage in order to elude complicated and risky treatment procedures The long, relatively asymptomatic first stage of T. b. gambiense sleeping sickness is one of the reasons why an exhaustive, active screening of the population at risk is recommended, in order to identify patients at an early stage and reduce transmission by removing their status of reservoir. Exhaustive screening requires a major investment in human and material resources. In Africa such resources are often scarce, particularly in remote areas where the disease is mostly found. As a result, some infected individuals may die before they can ever be diagnosed and treated. Treatment The type of treatment depends on the disease stage. The drugs used in the first stage are safer and easier to administer than those for second stage. Also, the earlier the disease is identified, the better the prospect of a cure. The assessment of treatment outcome requires follow up of the patient up to 24 months and entails laboratory exams of body fluids including cerebrospinal fluid obtained by lumbar puncture, as parasites may remain viable for long periods and reproduce the disease months after treatment. Treatment success in the second stage depends on drugs that cross the blood-brain barrier to reach the parasite.

Such drugs are toxic and complicated to administer. In total five different drugs are used for the treatment of sleeping sickness. These drugs are donated to WHO by manufacturers and distributed free of charge to disease endemic countries. Drugs used in first stage treatment: Pentamidine: discovered in 1940, used for the treatment of the first stage of T.b. gambiense sleeping sickness. Despite non-negligible undesirable effects, it is in general well tolerated by patients. Suramin:: discovered in 1920, used for the treatment of the first stage of T.b. rhodesiense. It provokes certain undesirable effects, including urinary tract and allergic reactions. Drugs used in second stage treatment: Melarsoprol: discovered in 1949, it is used for the treatment of both gambiense and rhodesiense infections. It is derived from arsenic and has many undesirable side effects, the most dramatic of which is reactive encephalopathy (encephalopathic syndrome) which can be fatal (3% to 10%). An increase in resistance to the drug has been observed in several foci, particularly in central Africa.

It is currently recommended as first-line treatment for the rhodesiense form, and as second-line for the gambiense form. Eflornithine: this molecule, less toxic than melarsoprol, was registered in 1990. It is only effective against T.b. gambiense. The regimen is complex and difficult to apply. Nifurtimox: A combination treatment of nifurtimox and eflornithine was introduced in 2009. It simplifies the use of eflornithine by reducing the duration of treatment and the number of IV perfusions, but unfortunately it has not been studied for T.b. rhodesiense. Nifurtimox is registered for the treatment of American trypanosomiasis but not for human African trypanosomiasis. Nevertheless, after safety and efficacy data provided by clinical trials, its use in combination with eflornithine has been included in the "WHO List of Essential Medicines" and is currently recommended as first-line treatment for the gambiense form. Both drugs are provided free of charge by WHO to endemic countries with a kit containing all the material needed for its administration.

Public private partnership In 2000 and 2001, WHO established public-private partnerships with Aventis Pharma (now Sanofi) and Bayer HealthCare which enabled the creation of a WHO-led control and surveillance programme, providing support to endemic countries in their control activities and the supply of medicines free of charge. The partnership was renewed in 2006, 2011 and 2016. The success in curbing the number of sleeping sickness cases has encouraged other private partners to sustain the WHO’s initiative towards eliminating the disease as a public health problem. WHO response WHO provides support and technical assistance to national control programmes. WHO provides the anti-trypanosome medicines free of charge to endemic countries through public-private partnerships with Sanofi (pentamidine, melarsoprol and eflornithine) and with Bayer HealthCare (suramin and nifurtimox). The conditioning and shipment of medicines is done in collaboration with MSF-Logistics. In 2009, WHO set up a biological specimens bank that is available to researchers to facilitate the development of new and affordable diagnostic tools.

The bank contains samples of blood, serum, cerebrospinal fluid, saliva and urine from patients infected with both forms of the disease as well as samples from uninfected people from areas where the disease is endemic. In 2014 a coordination network for human African trypanosomiasis was established under WHO leadership to ensure strengthened and sustained efforts to eliminate the disease. The stakeholders include national sleeping sickness control programmes, groups developing new tools to fight the disease, international and non-governmental organizations, and donors. The objectives of the WHO programme are to: strengthen and coordinate control measures and ensure field activities are sustained; strengthen surveillance systems; ensure accessibility to the diagnosis and the best treatment available; support the monitoring of treatment and drug resistance; develop an information database for epidemiological analysis, including the atlas of the human African trypanosomiasis, completed in collaboration with the Food and Agriculture Organization (FAO); ensure skilled staff by offering training activities; support operational research to improve diagnostic and treatment tools; promote collaboration with the FAO in charge of animal trypanosomiasis and the International Atomic Energy Agency (IAEA) dealing with vector control through male flies made sterile by radiation.

The 3 UN agencies along with the African Union have promoted the Programme Against African Trypanosomiasis (PAAT); synergize vector and disease control activities in collaboration with the Pan African Tsetste and Trypanosomosis Eradication Campaign (PATTEC) of the African Union. For more information contact: CDC - African Trypanosomiasis - General Information - East African Trypanosomiasis FAQs East African Trypanosomiasis FAQs To receive email updates about this page, enter your email address: Enter Email Address How can I prevent African trypanosomiasis and prevent other insect bites? What is East African trypanosomiasis? There are two types of African trypanosomiasis (also called sleeping sickness); each is named for the region of Africa in which they were found historically. East African trypanosomiasis is caused by the parasite Trypanosoma brucei rhodesiense, which is carried by the tsetse fly. Each year, a few hundred cases of East African trypanosomiasis are reported to the World Health Organization. However, many cases are not recognized or reported and the true number of new cases is higher.

Since 1967, 40 cases of East African trypanosomiasis have been diagnosed or treated in the United States, all among individuals who had traveled to eastern Africa. More on: West African Trypanosomiasis FAQs How is East African trypanosomiasis spread? A person will get East African trypanosomiasis if he or she is bitten by a tsetse fly infected with the Trypanosoma brucei rhodesiense parasite. The proportion of tsetse flies that are infected with this parasite is low. The tsetse fly is found only in rural Africa. Is East African trypanosomiasis a serious illness? Yes. If a person fails to receive medical treatment for East African trypanosomiasis, death will occur, usually within months. Where can you become infected with East African trypanosomiasis? East African trypanosomiasis is found in parts of Eastern and Southeastern Africa. More than 95% of cases are reported from Uganda, Tanzania, Malawi, and Zambia. What are the signs and symptoms of East African trypanosomiasis?

A bite by the tsetse fly is often painful and can develop into a red sore, also called a chancre. Fever, severe headaches, irritability, extreme fatigue, swollen lymph nodes, and aching muscles and joints are common symptoms of sleeping sickness. Some people develop a skin rash. Progressive confusion, personality changes, and other neurologic problems occur after infection has invaded the central nervous system. If left untreated, infection becomes worse and death will occur within months. How soon after infection will I have symptoms of East African trypanosomiasis? Symptoms usually within 1 to 3 weeks after an infective bite. Back To Top What should I do if I think I may have African trypanosomiasis? If you suspect that you may have East African trypanosomiasis, immediately consult with your health care provider, who will order several tests to look for the parasite. A skin biopsy may be done if you have a chancre. Blood tests will be done and a spinal tap may also be performed. What is the treatment for East African trypanosomiasis? Medical treatment of East African trypanosomiasis should begin as soon as possible and is based on the infected person’s laboratory results.

Medication for the treatment of East African trypanosomiasis is available through CDC. Hospitalization for treatment is usually necessary. Periodic follow-up exams that include a spinal tap are required for 2 years. Once infected, am I immune to East African trypanosomiasis? Even if you had the disease once, you can get re-infected. Who is at risk for contracting East African trypanosomiasis? Tsetse flies are found in woodland and savannah areas and they bite during daylight hours. Travelers to urban areas are not at risk. The persons most likely to be exposed to the infection are tourists, hunters, and others working in or visiting game parks. Villagers with infected cattle herds are also at risk. Can I take a medication to prevent East African trypanosomiasis? There is neither a vaccine nor recommended drug available to prevent East African trypanosomiasis. How can I prevent African trypanosomiasis and prevent other insect bites? Wear protective clothing, including long-sleeved shirts and pants. The tsetse fly can bite through thin fabrics, so clothing should be made of medium-weight material. Wear neutral-colored clothing.

The tsetse fly is attracted to bright colors and very dark colors. Inspect vehicles for tsetse flies before entering. The flies are attracted to moving vehicles. Avoid bushes. The tsetse fly is less active during the hottest period of the day. It rests in bushes but will bite if disturbed. Use insect repellant. Though insect repellants have not proven effective in preventing tsetse fly bites, they are effective in preventing other insects from biting and causing illness. Back To Top This information is not meant to be used for self-diagnosis or as a substitute for consultation with a health care provider. If you have any questions about the parasites described above or think that you may have a parasitic infection, consult a health care provider. Get Email Updates To receive email updates about this page, enter your email address: Enter Email Address Trypanosomiasis (sleeping sickness) | Infectious Disease of Tampa This disease will progress to cause mental deterioration, coma and ultimately death if left untreated. Causes Trypanosomiasis is caused by a parasite that is passed from person to person through tsetse fly bites.

Mother to child transmission is rare but possible, and it is also possible to contract trypanosomiasis through needle stick accidents in the hospital. Trypanosomiasis may be caused by one of two parasites, Trypanosoma brucei gambiense (T. b gambiense) and Trypanosoma brucei rhodesiense (T. b rhodesiense). T. b gambiense is more common, accounting for a vast majority of all sleeping sicknesses, and is contracted in areas of west and central Africa. T. b rhodesiense is found in east and southern Africa. The disease may progress at different paces depending on the parasite present. Trypanosomiasis caused by the more common T. b gambiense can take years to reach deadly stages, while T. b rhodesiense can cause a lethal infection in only a few months. Diagnosis, Treatment and Prevention Trypanosomiasis can be diagnosed using fluid from the site of the tsetse fly bite, affected lymph nodes and the blood or spinal fluids as the disease spreads to those systems. Treatment of early stage sleeping sickness is easier, and requires intravenous or intramuscular medications.

The kind of medication used may vary depending on the type of parasite present. Second stage trypanosomiasis is more difficult to treat and commonly requires a combination of intravenous medications. Prevention focuses on avoiding tsetse fly bites by using insect repellant and wearing long-sleeved clothing. These prevention efforts may also effectively help protect against more common tropical diseases spread by mosquitoes and other insects. There is a western version of trypanosomiasis, but it is far less common than the African version of the disease. American trypanosomiasis, or Chagas disease, is caused by the reduviid bug’s feces and may occur when a bite from this bug is scratched and the germs enter the body. American trypanosomiasis is endemic in Mexico, Central and South America. If you have recently returned from international travel and are not feeling well, please contact the medical team at Infectious Disease of Tampa at 813.915.5454, especially if a bug or animal bit you during your travel. Dr. Parul Anej is an expert in tropical diseases including trypanosomiasis and may other zoonotic conditions.

trypanosomiasis | pathology | Britannica.com Trypanosomiasis Trypanosomiasis, infectious disease in both humans and animals caused by certain members of the flagellate protozoa genus Trypanosoma and spread by certain bloodsucking insects. Representative protozoans. The phytoflagellate Gonyaulax is one of the dinoflagellates … © Merriam-Webster Inc. The genus Trypanosoma belongs to the family Trypanosomatidae, which is in the order Kinetoplastida. The life cycle of trypanosomes includes a stage spent in blood or other tissues of a vertebrate host and a stage in the gut of an invertebrate, typically a fly. About 20 species of Trypanosoma are known, of which only two—T. cruzi and T. brucei—cause disease in humans. Each species is responsible for a different disease. T.

cruzi causes American trypanosomiasis, also called Chagas’ disease , which occurs primarily in the Central and South American tropics and is spread by the bite of insects of the family Reduviidae, also known as “kissing bugs.” The parasite multiplies in the bloodstream and may enter the heart, liver, and spleen, where it causes extensive damage. T. brucei is responsible for African trypanosomiasis, or sleeping sickness , which occurs in equatorial Africa in two forms, both transmitted by the tse-tse fly (Glossina). East African, or Rhodesian, sleeping sickness is an acute form of the disease caused by the subspecies T. brucei rhodesiense . West African , or Gambian, trypanosomiasis is a slower-developing chronic form of the disease caused by T. brucei gambiense . Both organisms can eventually invade the brain, causing mental deterioration, coma, and death. Other Trypanosoma species cause economically important diseases in livestock: nagana , dourine , surra, and mal de caderas. Learn More in these related articles:

Question: Trypanosomiasis is an infectious disease spread by what?
Answer: Tsetse fly