What is sleeping sickness?
Sleeping Sickness (African Typanosomiasis) is an infectious disease of rural, undeveloped regions of tropical Africa, which is spread by the bite of the tsetse fly (Glossina).
It mainly affects those who live in the affected regions, but tourist who have not taken adequate precautions against the disease can also catch it.
There are two main types, generally found in fairly distant geographical areas; although there are countries (among then Uganda and Zaire) where both forms of sleeping sickness occur.
One variety, found mainly in east Africa, affects most animals, both wild herds (such as the antelope) and domestic cattle; although humans can also be affected. The other is usually found in West and Central Africa, and is passed from person to person via the fly.
What Are The Symptoms?
- Large red bumps around the bite
- Spasmodic bouts of fever
- Enlarged Lymph glands
- Slow slurred speech
- Unsteady walk
What Causes Sleeping Sickness?
Sleeping sickness is caused by single celled parasites called trypanosomes, which live in humans and animals. The Tsetse fly bites an infected person or animal, sucking out their blood. Only about one percent of the flies in an area carry the disease; but once infected, they remain so for the rest of their life span.
The parasites multiply in the fly’s gut, before migrating to its salivary glands, after a period of two to four weeks. When the fly bites another human or animal, the trypanosomes pass into new host. The parasites affect the blood, the heart and the lymphatic and central nervous systems.
How Is Sleeping Sickness Diagnosed And Treated?
Doctors in the West may be unfamiliar with the symptoms of sleeping sickness. Soothe disease may be undiagnosed for some time, although a doctor experienced in tropical medicine can usually recognize the tell tale signs immediately.
The first obvious sign is a large, red painful lump which appears after a few days at the site of the bite. With the West African form, the incubation period can last for years, and progress of the disease is slow and insidious.
Headaches, spasmodic bouts of fever, and swollen lymph glands are followed by tremors, unsteadiness of speech and movement extreme tethargy. Drooping eyelids vacant expression and distressing personality changes. Finally, victims are unable to swallow, or feed themselves and lapse into coma and die.
With the East African variety, symptoms appear after few days or weeks with a high fever, and on occasions, a rash on the torso, shoulders and thighs.
The parasites multiply rapidly in the blood stream, and the disease can proceed so swiftly that death can result from toxaemia (blood poisoning), or heart failure (from dilation and straining of the heart muscle), before treatment can be sought.
Treatments is with anti-parasites drugs, but these are administered with great caution, as they can have serious side effects.
When Should I See The Doctor?
You should see the doctor if you feel unusually tired all the time, following a trip to an area where the disease is prevalent.
What Will The Doctor Do?
To confirm the diagnosis, the doctor will examine samples of blood and lymph as well as spinal fluid, drawn off by a lumbar puncture (in which a hollow needle is inserted into the lower part of the spinal canal).
Treatment by suramin, pentamidine or melarsoprol. Suramin can cause kidney damage, so the doctor will need to carry out regular blood and urine tests if this drug is prescribed.
Sleeping Sickness is a serious illness, requiring constant medical surveillance and careful nursing. The patient will need a lengthy period of rest and convalescence at home, after the initial crisis is over.
What Can I Do To Avoid Sleeping Sickness?
Visitors to towns in Africa are at very little risk of catching the disease, although those planning a safari holiday or a visit to a rural area can be exposed to infection.
The visitor should avoid insect bites, by keeping the arms and legs covered and by using insect repellent on the skin, and insecticidal aerosol sprays in all rooms.
The drug pentamidine provides some measure of protection against sleeping sickness for the traveler over a limited period a special cases.
To have any effect on the local population, the drug has to be administered regularly to large numbers of people under medical supervision. This is obviously difficult with small, scattered rural communities. The most important preventative measures ain to eradicate the tsetse fly.
Is Sleeping Sickness Dangerous?
Yes, it is potentially fatal. Estimates of the numbers of cases range from 6,000 to more than 20,000 each year. Numbers tend to increase during times of war and famine, when social structures break down.
The disease has serious consequences for rural life in Africa, undermining the efforts of villages to improve their circumstances. It also has crucial economic effects on rural communities which are dependant on cattle. Wild animals provide a reservoir for the infection, although they do not succumb to the disease themselves, enabling it to be passed on to domestic cattle which die from it.
Left untreated, sleeping sickness is almost always fatal. The actual cause of death may sometimes by dysentery or pneumonia because damage to the immune system leaves the patient prey to these other infectious diseases.
If diagnosed and treated early, the patient has a good chance of making a full recovery. Although if treatment is delayed, there may be permanent damage to the brain and nervous system.