Trypanosomes

It is another hemoflagellate that cause two distinctly different forms of disease which is called African trypanosomiasis or sleeping sickness and is produced by Trypanosoma brucei gambiense and trypanosoma brucei rhodesiense.

 

Trypanosoma brucei gambiense

Physiology and Structure:

Trypomastiogote is an infective stage of the organism which is present in the salivary glands of transmitting tsetse flies. At this stage, the organsims has a free flagellum and an undulating membrane that runs along the body. Trypomastigotes are entered through the wound created by the fly bite. Tsetse flies are infective from week 4 to 6 after feeding on the blood from a diseased patient.

Tsetse Fly

taken from: https://www.iaea.org/NewsCenter/News/2002/tsetse_battle.shtml

 

Life Cycle:

Extracted from: Essentials of Human Parasitology

 

Clinical Syndromes:

Incubation period varies from a few days to weeks which will lead to chronic disease due to T.b.gambiense. Early symptoms such as occasional ulcer at the site of the fly bite. Overtime, other symptoms such as fever, myalgia and lymph node enlargement. during the period of witnerbottom's sign (the swelling of the posterior cervical lymph nodes), the patient exhibit hyperactivity.

Chronic diseases progresses to Central Nervous System (CNS) involvement with letharfy, tremors, mentall retardation and general deterioration. The final stages of chronic disease are convulsions, hemiplegia, incontinence occur and comatose state.

Death is the outcome of CNS damage and other infections like malaria or pneumonia.

 

Treatment, Prevention and Control:

  • Drugs such as suramin, with pentamidine are usually consumed at acute stages of the disease. In chronic disease with CNS involvement, the drug of choice is melarsoprol. Difluoromethylornithine has been used for the treatment of all stages of disease.
  • Controlling the breeding of tsetse flies by clearing brush, using insecticides, treating human cases to reduce transmission to flies.
  • People going to endemic areas should protect themselves with protective clothing and use screening, bed netting and insect repellents.

We do not take credit for any of the information found in this website. All the information is obtained from various forms of literature.

Parasite is defined as an organism that derives its nutrients from another living organism, the host. Parasitic diseases are usually referred to those caused by protozoa, helminths and arthropods which love at the expense of their host. Successful parasites are the ones who are able to maintain their own life processes without killing their host.

Several ways to distinguish parasites infection and bacteria/viruses infection:

  1. Parasites have a complex life cycle that involves the formation of resistant cyst in the organism. (it can usually survive for long periods outside the host.)
  2. Life cycle might involve an insect vector (carrier) that is important for the transmission of disease. In most cases, it is impossible to eliminate the vector effectively.
  3. Some parasites are capable of infecting both humans and animals, thus both can act as reservoirs for the infection. This is true for most protozal infections carried by insects.
  4. Many parasites has life cycle that requires enough time to allow for the various stages to mature, either in soil or in an insect or host.