The control of tsetse flies must be based on the practical application of ecological knowledge by methods involving either a direct attack upon the fly such as trapping or the use of insecticides or an indirect attack such as bush clearing or game destruction to eliminate the flys habitat or food supply. This article studies the expansion of tsetse fly in one part of kenya maasailand between 1900 and 1950. It follows the lines of investigation first suggested by fords work and examines in detail the interaction between changes in four elements in the mara ecosystem. Symptoms include fatigue, high fever, headaches, and muscle aches. The sterile insect technique for control of tsetse flies in africa by willem takken and michael weiss african trypanosomiasis and its major vector, the tsetse fly, have drawn worldwide attention due to the devasting effects they cause in large areas of tropical africa.
True fly species range from crane flies to fruit flies, as well as bee mimics like bee flies and hoverflies, and the everannoying friendly flies, midges, blow flies and face flies. The role of the trypanosomiases in african ecology a study of the tsetse fly problem ford, john on. They transmit trypanosomes that cause african sleeping sickness in humans and a disease called nagana in livestock. It has been christened the poverty fly and africas bane. Several studies have shown that temperature is one of the best predictors of tsetse range, predicting tsetse distributions in different regions of africa with around 80% accuracy rogers et. The reproductive cycle of tsetse flies occupies a minimum of 55 or 56 days at 23 o, made up of 12 days ovarian development of the first egg always in the right ovary, 3 or 4 days embryonic development, 7 days larval growth in utero, and 33 days as a pupa underground. It includes conditions of climate, vegetation, animal life, soil, and the effects of human activity. Tsetse fly abundance, trypanosome prevalence, and climate data collection. Paternal transmission of a secondary symbiont during. At first glance, it may be surprising why tsetse flies aren. Tsetse flies display a unique viviparous mode of reproduction where the offspring develops in utero where it is nourished by maternal milk gland.
Human african trypanosomiasis hat or sleeping sickness is a disease caused by humanpathogenic protozoan parasites of the trypanosoma brucei species. Ecology and behaviour of tsetse food and agriculture. The sterile insect technique for control of tsetse flies. In uganda, the tsetse fly glossina fuscipes fuscipes is responsible for transmission of the parasite in 90% of sleeping sickness cases, and co. The role of the trypanosomiases in african ecology. As a result of the economic impact of tsetsetransmitted trypanosomosis, a large amount of research literature has been produced.
The word is pronounced tsehtseh in the sotho languages and is easily rendered in other african languages. Travelers who go to subsaharan africa are at risk see map. The biology of tsetse flies jackson 1949 biological. Travelers who plan to spend a lot of time outdoors or. Since the beginning of the century much work has been done on the problems presented by trypanosomiasis and the tsetse fly in africa. The obligate bloodfeeding tsetse fly, the sole vector of human pathogenic african trypanosomes, harbors several bacterial symbionts that influence important aspects of its physiology and ecology. All these may be called environmental conditions or environmental factors. Zebra skin odor repels the savannah tsetse fly, glossina. The role of the trypanosomiases in african ecology a. The authors use a quantitative modelling framework to describe and explore the features of the biology of tsetse flies glossina spp.
Epidemiology of trypanosome infestations of the tsetse fly glossina pallidipes in the zambezi valley. Seasonal variation of tsetse fly species abundance and. The areas they inhabit may extend to several hundred kilometers and form what have been traditionally called fly belts. The identification of tsetse reservoirs and refugia mark h. The interaction of dispersal and control methods for the. This movie shows tsetse fly blood feeding, water excretion, pregnancy, birth of a larva, larval wandering and pupation.
Distribution and abundance of tsetse flies glossina spp. By contrast, it was difficult to demonstrate any effect of. Aspects of evolution and ecology of tsetse flies and trypanosomiasis in prehistoric african environment volume 5 issue 1 frank l. Tsetse find their hosts in large part through olfactory cues, but little is known about the cellular basis of olfaction in these flies. The tsetse the word tsetse means fly destructive to cattle, thus the name tsetse fly is redundant is an ovoviviparous vector of african trypanosomiasis. Ecology and distribution tsetsetransmitted animal trypanosomosis remains a major challenge to rural and agricultural development in western and south. Tsetse flies pose a major threat to the health and economy of subsaharan africa. Collection, identification and dissection of tsetse flies.
Fly age was known to be the most significant factor by far in t. For a more detailed description of the life cycle and general biology of tsetse flies, see stephen leaks excellent book. Tsetse fly belongs to genus glossina of family glossinidae and is pronounced tsetse or teetsee or setsee. Recently, tsetse without the fly has become more common in english, particularly in the scientific and development communities. The importance of ecological studies in the control of. Sites were selected through stratified random subsampling of the major vegetation types in the area bouyer et al. Tsetse fly zoology for ias, ifos and other competitive exams. Although tsetse are found over an area estimated to be at least 10 million square kilometers, the distribution of the flies is discontinuous. Lusch,1,4 and joseph maitima5 1department of geography, michigan state university, michigan 48824 usa 2center for global change and earth observations cgceo, michigan state university.
An advance of this species is also mentioned from sudan abdel razig et id. Adult bloodfeeding tsetse flies, trypanosomes, microbiota. Geography and ecology the maasai mara national reserve mmnr is located in southern kenya, adjacent to. The female fly has a uterus wherein an individual egg hatches, the resulting larva feeding on secretions provided by milk glands. Mitochondrial dna variation and the role of history vs. The control of tsetse flies must be based on the practical application of ecological knowledge by methods involving either a direct attack upon the fly such as trapping or the use of insecticides or an indirect attack such as bush clearing or game destruction to eliminate the fly s habitat or food supply. Temporal abundance of tsetse flies was estimated by monthly sampling for a period of 15 months in 2014 and 2015 in the village of emboreet, which borders tarangire national park figure 1.
We hypothesized that certain chemical components of zebra skin odor play a role in. We used a spatial model of a riverine tsetse fly species glossina palpalisgambiensis life cycle to investigate the interaction between their dispersal and three control methods and to document these interactions using sensitivity analyses. Odor coding in the antenna of the tsetse fly glossina. The epidemiological aspects and patterns of the disease are examined under the changing climatic conditions of the pleistocene and during later times, when africa was opened up by western exploration. A comprehensive study of genic variation in natural populations of drosophila melanogaster. They are large biting flies found in africa that suck blood of vertebrates and transmit several protozoan diseases. Tsetse flies are similar to other large flies but can be distinguished as they fold their wings completely when at rest so that one wing rests directly on top of the other. Within these belts are patches of forest and bush where. In central and west africa, they live in the forests and vegetation along streams. Their aim has been the control or elimination of the disease. Tsetse fly, genus glossina, any of about two to three dozen species of bloodsucking flies in the housefly family, muscidae order diptera, that occur only in africa and transmit sleeping sickness african trypanosomiasis in humans and a similar disease called nagana in domestic animals.
To set the stage on how modeling has been and can be used in tsetse control, a brief outline of the controversies in this area is useful. The model is currently limited to gallery forest habitat inhabited by glossina palpalisgambiensis in the dry season in the sub. Mathematical modeling, spatial complexity, and critical. This has been attempted either directly by chemotherapeutic means with or. Cattadori3 1nelson mandela african institution of science and technology. Chemosensory receptors in tsetse flies provide link. A few species do not fly but live as parasites or on islands or alpine areas. Although zebras are nonpreferred hosts, the possible chemical basis of their avoidance by tsetse flies is unknown. Tsetse populations have extended i56 km east wards since 1972 in the ngabe area in zambia mumba, 1980. The pan african trypanosomosis and tsetse eradication campaign pattec were borne. Tsetse flies inhabit rural areas, living in the woodlands and thickets that dot the east african savannah.
Challier skip to main content accessibility help we use cookies to distinguish you from other users and to provide you with a better experience on our websites. Pandemics of cholera, influenza, and other diseases seriously impact human populations. Such clearcut panzootic outbreaks of diseases in wildlife are probably rare events. Tsetse flies survive in a variety of environments across tropical africa, often rising to large numbers, despite their low birth rate of one offspring every seven to nine days. Tsetse flies genus glossina are the only vector for the parasitic trypanosomes responsible for sleeping sickness and nagana across sub. Pdf distribution and abundance of tsetse flies glossina. While the shift to private ranches has resulted in some fenced enclosures. The role of the trypanosomiases in african ecology a study of the tsetse fly problem. If this is the first time you use this feature, you will be asked to authorise cambridge core to connect with your account. The main problem in the application of this method lies in the fact that the scientific community studying tsetse habitat and ecology has not adopted lccs yet, therefore the comparison of ad hoc defined classes and standard ones can be troublesome. Article pdf available in journal of animal ecology 553. The word tsetse means fly in tswana, a bantu language of southern africa. These parasites are transmitted by the tsetse fly vector in which parasites have to surmount several natural bottlenecks to eventually reach the insect salivary glands and to differentiate into a final stage that is infective for a. The accounts of this work have been written mainly by the doctors, veterinarians and entomologists who have carried it out.
It is essentially the biophysical environment that surrounds, influences and is utilized by a species population. We carried out a systematic physiological analysis of. Tsetse fly mortality of both pupal and adult flies also increase with temperature hargrove 2004. Bouyer wednesday 04 february h30 identification of species, wing 9h00 3h ecology of tsetse flies 1h taxonomy and distribution of tsetse 1h dissection of tsetse principles 30 min j. African trypanosomiasis, also called african sleeping sickness, is a parasitic disease spread by the tsetse fly. Aspects of evolution and ecology of tsetse flies and. Both forms of sleeping sickness are transmitted by the bite of the tsetse fly glossina species. Climate essentially temperature and vapour pressure deficit governs the spread of the fly over the. Population structure of the tsetse fly glossina pallidipes. The ecology or tsetse 09 trade cattle roads popham, 1972. A dynamic species distribution model of glossina subgenus morsitans. We discuss the identification of odorant and gustatory. Populations of some species remain depleted and the persistence of rinderpest in eastern africa continues to threaten bovid populations.
Tsetse flies exclusively feed on blood, lactate and give birth to live. The tsetse fly vector transmits the protozoan trypanosoma brucei, responsible for human african trypanosomiasis, one of the most neglected tropical. Available formats pdf please select a format to send. A dynamic species distribution model of glossina subgenus. They use olfactory receptors to process chemical signals in their environments to find food, escape from predators, and locate suitable larviposition sites. A spatial genetics approach to inform vector control of. Equitable and efficient means to minimise adverse impacts of livestock on the environment.
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