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 night-time insomnia 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 ycars may pass before an infected person becomes sick, and the disease develops more slowly, although it can still 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 carly, 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 four to eight weeks without causing problems, but infants can die in this carly 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' discase. 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 orders blood tests to look for protozoa or antibodies* to the organism. In cases in which the doctor suspects sleeping sickness, a sample drawn from fluid surrounding the brain and spinal cord or tissuc from swollen lymph nodes may be examined for evidence of the discase. If a patient has a suspicious-looking skin lesion*, a biopsy is 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 cosely by a doctor for at least two years to see whether they show any signs that they still have the infection.

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 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 ycars 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 discase is common to take precautions. In Africa precautions include 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 África sleep under netting and avoid riding in the backs of open trucks because dust from moving vehicles attracts the flies. It is also advisable not to 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.

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