Travel Health Information Sheet
Trypanosomiasis is a parasite that spreads to humans and animals by certain kinds of insects. There are two main types:
- African trypanosomiasis - also called sleeping sickness.
- American trypanosomiasis - often known as Chagas’ disease.
Sleeping sickness is found in East and West Africa. It is spread by bites from an insect called a tsetse fly - a grey-brown insect the size of a honey bee. Tsetse flies live the flat grasslands of the African plains, including game reserves, which are known as the savannah.
Chagas’ disease is found mainly in South and Central America and Mexico. It is spread by contact with waste (faeces) from an insect called a triatomine bug, also known as a cone nosed or kissing bug. These bugs live in the walls and roofs of poorly built houses, especially those made from mud and thatch. These bugs defecate at same time they bite humans and animals. The parasite passes out in bug faeces and enters human blood through the skin, mouth or nose, if the bite is scratched or rubbed.
There are two different types of sleeping sickness: East African (caused by a type of the parasite called rhodensiense) and West African trypanosomiasis (caused by a different kind of the parasite, called gambiense).
Tsetse fly bites are very painful. Once bitten, a skin ulcer (chancre) usually forms at the site. Your glands (lymph nodes) may also become swollen. After this, fever and headache occurs, along together with extreme tiredness lasting for several weeks. At this stage, with East African sleeping sickness, there can be very serious medical problems, such as fluid in the lungs and heart failure, which can be fatal.
The parasite can spread to the brain and cause inflammation, confusion, irritability and personality changes. If the right treatment is not given, the infected person gradually becomes sleepier and eventually lapses into a coma. This is why the disease is called “sleeping sickness”. If you have East African sleeping sickness, you usually get ill much faster than with the West African type. Both types are fatal if left untreated.
At first symptoms are quite vague and include; loss of appetite, sickness and diarrhoea. An ulcer can develop, if there is direct skin contact with infected faeces. If the parasite gets into the eyes, it causes redness, swelling and infection.
The first symptoms may not develop further. Sometimes more serious symptoms can appear a long time after your first symptoms have subsided. These can include chest pain, clots, palpitations, shortness of breath and heart problems, which can be fatal. In addition, digestive problems, such as difficulty in swallowing or keeping food down and constipation may develop. This is called mega disease.
Both types of trypanosomiasis are rare in travellers.
However, you are at risk of sleeping sickness if you get bitten by tsetse flies in Africa. This is more likely if you spend a lot of time outside in rural areas, go on safari or visit game reserves. In the past few years, there have been cases of sleeping sickness in travellers returning to Europe from countries in Africa such as Malawi, Tanzania and Uganda.
You are at risk of Chagas’ disease if you have contact with triatomine bugs in risk countries. Occasionally Chagas’ disease is reported after consumption of food or drinks contaminated with bug faeces - an outbreak at a school in Venezuela was linked to contaminated fruit juice.
Very rarely, both parasites can be spread by blood transfusions, organ transplants, via contaminated medical equipment or from a mother to her baby during pregnancy and breast feeding.
If you are in Chagas’ risk areas, try to avoid staying in poorly constructed buildings, especially those made from mud or thatch.
Tsetse flies like bright or dark colours and can bite through clothes made of thin fabrics. Carefully check cars and vehicles before you get in, as the flies are attracted to the motion and dust from moving vehicles.
See a doctor as soon as possible if you have any symptoms.
Yes, there are several drugs used to treat both types the disease, but treatment is complicated, can be unpleasant and may cause serious side effects. If your doctor thinks you have trypanosomiasis, you must be referred to a doctor who specialises in tropical diseases.
No – avoiding tsetse fly bites and reduviid bug faeces is the only way to prevent infection.
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