African sleeping sickness, also known as African trypanosomi-asis, is transmitted by its biological vector, the day-biting tsetse fly. The disease is important because it can be contracted by residents and visitors in a wide area across the middle of the African continent. The causative protozoan has an interesting way of protecting itself against the host's immune system.
The first symptoms of African trypanosomiasis appear within a week after a person is bitten by an infected tsetse fly. A tender nodule develops at the site of the bite. The regional lymph nodes may enlarge, but symptoms may all disappear spontaneously. Weeks to several years later, recurrent fevers develop that may continue for months or years. Involvement of the central nervous system is marked by gradual loss of interest in everything, decreased activity, and indifference to food. The eyelids droop, the individuals fall asleep while eating or even standing, the speech becomes slurred, coma develops, and eventually death ensues.
African sleeping sickness is caused by the flagellated protozoan, Trypanosoma brucei. The organisms are slender, with a wavy, undulating membrane and an anteriorly protruding flagellum (figure 26.22). There are two subspecies that are morphologically identical, T. brucei rhodesiense and T. brucei gambiense. The rhode-siense subspecies occurs mainly in the cattle-raising areas of East Africa, whereas the gambiense subspecies occurs mainly in forested areas of Central and West Africa. Both are transmitted by tsetse flies, a group of biting insects of the genus Glossina.
Figure 26.22 Trypanosoma brucei in the Blood Smear of an Individual with African Sleeping Sickness (African Trypanosomiasis)
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A Guide to Natural Sleep Remedies. Many of us experience the occasional night of sleeplessness without any consequences. It is when the occasional night here and there becomes a pattern of several nights in arow that you are faced with a sleeping problem. Repeated loss of sleep affects all areas of your life The physical, the mental, and theemotional. Sleep deprivation can affect your overall daily performance and may even havean effecton your personality.