African trypanosomiasis is an infectious medical condition which humans and animals acquire via the tsetse fly of the Glossina species. This vector occurs only in rural Africa, and there is a serious public health problem from the disease in certain parts of sub-Saharan Africa. The tsetse fly bites during the daytime and tends to be present in woodland and savannah areas. In West Africa, the insects tend to live in forests and vegetation along streams.
Groups at Risk
At especial risk for acquisition of human African trypanosomiasis are villagers with herds of cattle that have the disease. Moreover, travelers to nonurban areas where the disease occurs will be at risk. This includes tourists, hunters, and those who work in game parks. This medical condition does not usually affect people in urban areas of Africa (Centers for Disease Control, 2010).
Rural areas, therefore, may suffer economic loss when the disease affects livestock there. Furthermore, spread of the infection increases when there is displacement of residents in the community because of war or poverty. Naturally, the health care systems in these circumstances will weaken, and proper diagnostic and therapeutic tools may not be available to control the epidemic.
Rural populations which depend upon agriculture, fishing, animal husbandry, and hunting will encounter the most exposure to the tsetse fly and the disease.
Two Forms of African Trypanosomiasis
There are two forms of African trypanosomiasis. East African trypanosomiasis is the result of infection with Trypanosoma brucei rhodesiense, and West African trypanosomiasis stems from Trypanosoma brucei gambiense infection. In both forms, the transmission may occur through either the male or female tsetse fly. Ninety-five percent of all reported cases of human African trypanosomiasis are due to Trypanosoma brucei gambiense.
These microorganisms which cause the disease are protozoan hemoflagellates.
There may be 30,000 cases of human African trypanosomiasis now present, and for many years there were 10,000 new cases of it annually. However, the number of new cases each year has recently declined.
Most cases of West African trypanosomiasis, or Gambian sleeping sickness, occur in Central Africa. East African trypanosomiasis, however, tends to infect people in Uganda, Tanzania, Malawi, and Zambia.
Sources
- Centers for Disease Control. (2010). Parasites—African trypanosomiasis (also known as sleeping sickness) Retrieved January 19, 2012.
- World Health Organization. (2012). African trypanosomiasis (sleeping sickness). Fact sheet. Retrieved January 19, 2012.
Disclaimer: The information contained in this article is for educational purposes only and should not be used for diagnosis or to guide treatment without the opinion of a health professional. Any reader who is concerned about his or her health should contact their physician for advice.
Michael Koger - Dr. Koger obtained his medical education at Meharry Medical College and specialized in Internal Medicine.
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