Trypanosomiasis african sleeping sickness biology essay
Trypanosoma brucei disease
The latter gives us confidence to interpret the magnitude of R0 values in the same way that we interpret R0 values for single-host pathogens and we can readily consider control effort, even if it is directed at a single host species Roberts and Heesterbeek, The tzetze fly fly is endemic in parts of sub-Saharan Africa. The resulting neurological symptoms include severe headache, mental dullness and apathy , a weary shuffling gait, tremors, spastic or flaccid paralysis , chorea, and a profound sleepiness that develops during a meal or when the patient is standing or walking. This has not yet been demonstrated in T. We constructed mechanistic models for the basic reproduction number, R0, of Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense, respectively the causative agents of West and East African human sleeping sickness. Finally, we use the sensitivity of R0 to various biological parameters in order to comment on the likely efficacy of control methods that target these parameters. This approach also complements the drive to model the distributions of both tsetse and sleeping sickness using variables derived from satellite imagery Rogers and Randolph, In the West African or Gambian type, T. While in Africa, you contracted African Trypanosomiasis, better known as sleeping sickness. You get up out of your seat or from a certain stand, and all you feel from one foot, leg, hand, or arm is an uncomfortable tingling sensation. Recently, evidence has also emerged to suggest that aparasitaemic asymptomatic human infections may constitute an overlooked reservoir of disease that contributes to the maintenance of disease foci [ 6 ]. In this manner, the disease can distribute rather rapidly in populated countries with this type of fly.
Usually 12 to 15 days elapse before flies that have picked up the parasites become infective toward humans. It is becoming increasingly clear that chromatin remodelling must play a critical role in ES control.
Diagnosis and treatment The earlier that sleeping sickness is diagnosed and treated, the greater the chances for recovery. This therapy is simpler than the regiment with Eflornithine ; nevertheless, it is non effectual against Trypanosoma brucei rhodesiense.
Trypanosomes are highly adapted for life in the hostile environment of the mammalian bloodstream, and have various adaptations to their cell biology that facilitate immune evasion.
That is, to spread and persist, the parasite is obligated to colonize and mature in tsetse flies. Vincendeau, The ability to occasionally detect parasite genetic material using PCR from these individuals supports the assertion that they harbour active infections, and they have consequently received increased attention in recent years.
In this paper we use the next-generation matrix approach to construct mechanistic models for R0 for West and East African sleeping sickness. Trypanosomiasis, normally known as African kiping illness, is a vector-borne parasitic disease World Health Organization, The basic reproduction number R0 is a key quantity in epidemiology that is defined for single-host pathogens as the expected number of secondary cases arising from a primary case in a wholly susceptible population.
Trypanosoma gambiense classification
Transmission occurs to humans by tsetse flies bites. Usually 12 to 15 days elapse before flies that have picked up the parasites become infective toward humans. We use the models to perform global sensitivity analyses for R0. Historically, epidemics of West African sleeping sickness were controlled in part through the administration of prophylactic doses of pentamidine to village populations. Even for the subset of flies that are genetically susceptible to infection of the midgut, this susceptibility sharply decreases after the first bloodmeal Welburn and Maudlin, The kinetoplastans are known by their characteristic scourge Hickman, The 2nd phase, known as the encephalitic phase is when the parasite has made its manner past the blood-brain barrier and into the cardinal nervous system. How Stuff Works 1 This tingling sensation is caused by paresthesia. Depression is the general name for a family of illnesses known as depressive disorders that can not only effect person mood, and internal thoughts, but also the outwardly physical function Article 2. Information obtained from these tests is then used to determine the stage of disease and course of treatment. For West African sleeping sickness, our results indicate that the proportion of bloodmeals taken from humans by Glossina fuscipes fuscipes is the most important factor, suggesting that differences in the exposure of humans to tsetse are fundamental to the distribution of T.
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