Colin Snow
Sleeping sickness, also known as human African trypanosomiasis (HAT), is a vector-borne parasitic disease caused by the parasite Trypanosoma brucei. The parasite is transmitted to humans by the bite of a tsetse fly (Glossina species) found in rural parts of sub-Saharan Africa. The disease occurs in two stages, with the first stage causing mild, flu-like symptoms, and the second stage causing more severe symptoms affecting the brain and central nervous system, including sleep cycle disturbances, confusion, and poor coordination. If left untreated, sleeping sickness is usually fatal. While there is no vaccine or drug to prevent sleeping sickness, early diagnosis and treatment are crucial and can be lifesaving.
| Characteristics | Values |
|---|---|
| Other names | Human African trypanosomiasis (HAT), African sleeping sickness, African trypanosomiasis |
| Cause | Parasitic infection from the bite of a tsetse fly (Glossina species) |
| Parasite | Trypanosoma brucei |
| Types | Trypanosoma brucei gambiense (92% of cases), Trypanosoma brucei rhodesiense (8% of cases) |
| Transmission | Bites from infected tsetse flies, which acquire the parasite from infected humans or animals |
| Symptoms | Fever, headaches, itchiness, joint pains, enlarged lymph nodes, sleep disturbances, confusion, poor coordination, numbness, lethargy, convulsions, behavioural changes |
| Diagnosis | Detecting parasite in blood smear, lymph node fluid, or other body fluids; lumbar puncture to analyse cerebrospinal fluid (CSF) and determine disease stage |
| Treatment | Pentamidine or suramin for early-stage T. brucei gambiense; eflornithine, nifurtimox, melarsoprol, or fexinidazole for late-stage disease; acoziborole as a potential new oral treatment |
| Prevention | Preventing tsetse fly bites through protective clothing, insect repellent, etc.; early diagnosis and treatment |
| Affected regions | Rural areas in 36 sub-Saharan African countries, including the Democratic Republic of the Congo, Zambia, and Zimbabwe |
| At-risk population | Approximately 70 million people |
| Case reduction | 97% reduction in new cases over the last 20 years |
Explore related products
What You'll Learn
Sleeping sickness is caused by a parasite
Sleeping sickness, or African trypanosomiasis, is a disease caused by a parasite. The parasite in question is called Trypanosoma brucei and it is transmitted to humans by the bite of an infected tsetse fly. Tsetse flies are found in sub-Saharan Africa, and only certain species carry and transmit the parasite. The disease has two forms, depending on the parasite subspecies: Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense. The former causes a chronic illness and accounts for over 92% of reported cases, while the latter causes an acute illness and accounts for 8% of reported cases.
The parasite takes advantage of the host's immune cells' dependence on rhythmic regulation, attacking the internal clock of the cells to improve its survival and multiplication. This disruption to the host's internal clock results in alterations to the sleep-wake cycle, body temperature, and hormonal regulation. The first stage of the disease typically involves mild, flu-like symptoms such as fever, headache, itchiness, and joint pains. These initial symptoms appear one to three weeks after the bite.
The second stage of sleeping sickness occurs when the parasites cross the blood-brain barrier and affect the central nervous system. This stage involves more severe symptoms such as confusion, poor coordination, numbness, and trouble sleeping. The appearance of these symptoms indicates that the infection has progressed to the neurological phase. Treatment protocols differ depending on whether the central nervous system has been affected, with more intensive drugs required to eliminate the parasites from the brain and spinal cord during the second stage.
Diagnosis of sleeping sickness involves detecting the parasite in a blood smear or lymph node fluid. A lumbar puncture, or spinal tap, may also be performed to analyze the cerebrospinal fluid and determine the stage of the disease. While there is no vaccine or drug to prevent sleeping sickness, early diagnosis and treatment are crucial for improving outcomes. Preventing insect bites from tsetse flies is the best way to avoid infection.
Unlocking Overnight Hair Magic with French Braids
You may want to see also
Explore related products
It is transmitted by the bite of a tsetse fly
Sleeping sickness, or human African trypanosomiasis (HAT), is a vector-borne parasitic disease. It is caused by the parasite Trypanosoma brucei, which is transmitted to humans by the bite of an infected tsetse fly (Glossina species). Tsetse flies are found only in sub-Saharan Africa, and only certain species transmit the parasite. Male and female tsetse flies feed exclusively on blood and act as vectors for transmitting the parasite to humans and livestock. Trypanosome transmission is restricted to specific rural ecological foci.
Sleeping sickness occurs when the parasite Trypanosoma brucei gambiense (West Africa) or Trypanosoma brucei rhodesiense (East Africa) is introduced into the body following a bite by a tsetse fly that had itself become infected by biting humans or animals harbouring the parasite. Humans are infected by two types, Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense. Trypanosoma brucei gambiense 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.
The first stage of the disease typically causes mild, flu-like symptoms, such as fever, headaches, itchiness, joint pains, enlarged lymph nodes, and intermittent fever. These symptoms can make it hard to diagnose sleeping sickness, as they are similar to those of many other diseases. The parasites can also cause changes in the sleep/wake cycle, body temperature, and hormonal regulation.
If the disease remains untreated, it progresses to the second stage, which is more severe and affects the brain and central nervous system. During this stage, people may experience neuropsychiatric symptoms such as sleep disruption, confusion, lethargy, convulsions, behaviour changes, poor coordination, and sensory disturbances. The appearance of these more obvious symptoms indicates that the disease has progressed to the neurological phase.
The best way to prevent infection is to prevent bites from tsetse flies. This can be done by wearing protective clothing, using insect repellent, and avoiding bushes.
Interiors: The Essence of a Good Night's Sleep
You may want to see also
Explore related products
Symptoms include fever, headaches, sleep disturbances, and confusion
Sleeping sickness, or human African trypanosomiasis (HAT), is a vector-borne parasitic disease caused by the parasite Trypanosoma brucei. It is transmitted to humans by the bite of an infected tsetse fly, which is found in rural parts of sub-Saharan Africa. The disease occurs in two stages, with the first stage typically causing mild, flu-like symptoms, including fever, headaches, itchiness, and joint pains. This begins one to three weeks after the bite.
The second stage of the disease, which can begin weeks to months later, affects the brain and central nervous system and causes more severe symptoms such as confusion, poor coordination, numbness, and trouble sleeping. Sleep-wake disturbances are a leading feature of this stage and give the disease its common name, "sleeping sickness". Those affected experience sleep inversion, resulting in daytime sleep and somnolence, and nighttime periods of wakefulness and insomnia. They may also experience episodes of sudden sleepiness and fever dreams, which can be disturbing and cause them to wake up during the night.
The parasite disrupts the host's circadian clock by taking advantage of the host immune cells' dependence on rhythmic regulation. It attacks the internal clock of the cells to improve its survival and multiplication. This results in disruptions to the sleep/wake cycle, body temperature, and hormonal regulation.
Diagnosis of sleeping sickness involves detecting the parasite in a blood smear or lymph node fluid. A lumbar puncture is often needed to determine the stage of the disease and confirm central nervous system involvement. Treatment for sleeping sickness is complex and requires specific skills. Early diagnosis is crucial to avoid progressing to the neurological stage, which has more complex and risky treatments. Without treatment, sleeping sickness is usually fatal.
Sleep Studies: Effective Insomnia Treatment?
You may want to see also
Explore related products
Treatment is complex and has historically been toxic
Sleeping sickness, or human African trypanosomiasis (HAT), is a vector-borne parasitic disease caused by the parasite Trypanosoma brucei. Humans are infected by two types, Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense, which are transmitted by the bite of an infected tsetse fly. The disease occurs in rural areas of sub-Saharan Africa, with around 70 million people at risk in 36 countries.
The disease progresses in two stages, with the first stage typically causing mild, flu-like symptoms such as fever, headaches, itchiness, joint pains, and enlarged lymph nodes. During this stage, the parasites are present in the bloodstream, and the disease can be difficult to diagnose. If left untreated, the disease progresses to the second stage, where the parasites cross the blood-brain barrier and invade the central nervous system. This stage is characterised by more severe symptoms such as sleep disturbances, confusion, sensory disturbances, poor coordination, and behavioural changes.
Treatment for sleeping sickness is complex and has historically been toxic. Early diagnosis is crucial as treatment becomes more challenging and risky once the disease progresses to the neurological stage. The type of treatment depends on the parasite species and the stage of the disease. Drugs used in the first stage, such as pentamidine for T. b. gambiense and suramin for T. b. rhodesiense, have relatively mild side effects and are easy to administer. However, treatment in the second stage is more complex and toxic as the drugs need to cross the blood-brain barrier.
For many decades, the only treatment available for sleeping sickness was melarsoprol, a drug developed in the 1940s. Derived from arsenic, melarsoprol was highly toxic, causing death in about 5% of patients from encephalopathy. In 2009, a safer combination treatment called NECT was introduced, consisting of pills and intravenous infusions. However, NECT still required administration by trained staff in specialised hospitals, which presented challenges for patients and health systems in resource-constrained settings. More recently, an oral treatment called fexinidazole has been approved for use in some countries, providing a simpler and more accessible option for treating sleeping sickness.
How Sleep Affects Your Blood Pressure
You may want to see also
Explore related products
The number of cases has decreased in recent years
Sleeping sickness, or human African trypanosomiasis (HAT), is a vector-borne parasitic disease caused by the parasite Trypanosoma brucei. Humans are infected by two types of the parasite: Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense. The disease is transmitted to humans by bites from tsetse flies (Glossina species) that have acquired the parasites from infected humans or animals. Tsetse flies are found only in sub-Saharan Africa, and only some species transmit the parasite.
The World Health Organization (WHO) has reported a significant decrease in the number of sleeping sickness cases in recent years, with fewer than 600 cases of the T. b. gambiense strain diagnosed in 2023, down from over 38,000 in 1998. This decrease can be attributed to sustained control efforts, which have reduced the number of new cases by 97% in the last 20 years. The number of cases has also fallen due to efforts to combat the disease, with fewer than 1,000 new cases reported in 2018. However, it is important to note that the actual number of cases may be higher, as social instability and lack of access make it challenging to establish an accurate count.
The reduction in sleeping sickness cases is a positive development, as the disease can be fatal if left untreated. The availability of effective treatments, such as fexinidazole, which can be taken orally for either stage of Trypanosoma brucei gambiense, has played a crucial role in reducing the disease's impact. Additionally, the development of NECT, a safer combination treatment of pills and intravenous infusions, has contributed to the decline in cases.
Despite the progress made, it is important to remain vigilant. The relaxation of surveillance could lead to a rise in cases, as observed in Guinea following the Ebola outbreak in 2013. Furthermore, the complex and challenging nature of diagnosis and treatment for sleeping sickness means that early detection and intervention are critical to preventing the progression of the disease to the neurological stage, which is more difficult to treat.
To further reduce the number of sleeping sickness cases, the WHO has set targets for eliminating the disease as a public health problem and interrupting transmission. The development of new oral treatments, such as acoziborole, a single-dose oral drug, holds promise for achieving these goals and ensuring the sustainable elimination of sleeping sickness.
Sleep Deprivation: Staying Awake for a Week
You may want to see also
Frequently asked questions
Sleeping sickness, also known as African trypanosomiasis or Human African trypanosomiasis (HAT), is a disease caused by a parasite called Trypanosoma brucei. It is transmitted to humans by the bite of a tsetse fly (Glossina species) found in sub-Saharan Africa.
Sleeping sickness occurs in two stages. The first stage is characterised by mild, flu-like symptoms such as fever, headaches, itchiness, joint pains, enlarged lymph nodes, and intermittent fever. The second stage is more severe and affects the brain and central nervous system, causing sleep disturbances, confusion, poor coordination, numbness, behavioural changes, and sensory disturbances.
There is no vaccine or drug to prevent sleeping sickness. Prevention involves avoiding bites from tsetse flies. Diagnosis and treatment are complex and require specific skills. Treatment for sleeping sickness has traditionally been complex and toxic, with melarsoprol being the only available option, which is derived from arsenic and can be fatal. However, in recent years, new treatments have been developed, such as NECT (a combination of pills and intravenous infusions) and fexinidazole, an oral cure.
