Guinea worm larvae

Guinea worm larvae

The guinea worm during its middle life stage as it matures within a water flea. The larvae can only grow to adulthood within a human host.
Mentioned in: Guinea Worm Infection
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The disease is spread by drinking water containing the Guinea worm larvae. Communities that are usually affected by GWD are those that don't have access to safe drinking water.
The worm eggs then hatch Guinea worm larvae (L1 larvae stage) which are then consumed by copepods and take approximately two weeks to develop and become infective mature larvae (L3 larvae) within the copepods.
The full multiscale model presented in this paper is based on monitoring the dynamics of ten populations at any time t, which are susceptible humans [S.sub.H](t) and infected humans [I.sub.H](t) in the behavioural human environment; infected copepods [I.sub.C] in the human biological environment; mature Guinea worms [W.sub.M](t) and fertilized female Guinea worms [W.sub.F](t) in the biological human environment (within-host parasite dynamics); Guinea worm eggs [E.sub.W](t) and Guinea worm larvae [L.sub.W](t) in the physical water environment; susceptible copepods [S.sub.E](t) and infected copepods [I.sub.E](t) in the physical water environment; and gastric juice [G.sub.J](t) in the human biological environment.
In the human population, this uptake of infected copepods, which harbour Guinea worm larvae, is the transmission of Guinea worm parasite from the physical water environment to susceptible humans who become infected humans.
The last three equations of the model system (1) describe the evolution with time of Guinea worm larvae [L.sub.W](t), susceptible copepods SE(t), and infected copepods [I.sub.E](t) in the physical water environment, respectively.
Figure 4 shows graphs of numerical solutions of model system (1) showing propagation of (a) population of infected humans ([I.sub.H]), (b) population of infected copepods ([I.sub.E]), (c) population of Guinea worm eggs in the physical water environment, and (d) population of Guinea worm larvae in the physical water environment, for different values of natural death rate of Guinea worm eggs in the physical water environment [[mu].sub.W]: [[mu].sub.W] = 0.005, [[mu].sub.W] = 0.5, and [[mu].sub.W] = 0.9.
Figure 5 shows graphs of numerical solutions of model system (1) showing propagation of (a) population of infected humans ([I.sub.H]), (b) population of infected copepods ([I.sub.E]), (c) population of Guinea worm eggs, and (d) population of Guinea worm larvae in the physical water environment, for different values of natural death rate of Guinea worm larvae in the physical water environment [[mu].sub.L]: [[mu].sub.L] = 0.005, [[mu].sub.L] = 0.5, and [[mu].sub.L] = 0.9.
Figure 6 shows graphs of numerical solution of model system (1) showing propagation of (a) population of infected humans ([I.sub.H]), (b) population of infected copepods ([I.sub.E]), (c) population of Guinea worm eggs in the physical water environment, and (d) population of Guinea worm larvae in the physical water environment, for different values of natural death rate of mature worms inside a single infected human host [[mu].sub.M]: [[mu].sub.M] = 0.9, [[mu].sub.M] = 0.09, and [[mu].sub.M] = 0.009.
Figure 7 shows graphs of numerical solution of model system (1) showing propagation of (a) population of infected humans ([I.sub.H]), (b) population of infected copepods ([I.sub.E]), (c) population of Guinea worm eggs, and (d) population of Guinea worm larvae in the physical water environment, for different values of natural death rate of fertilized female worms inside a single infected human host [[mu].sub.F]: [[mu].sub.F] = 0.9, [[mu].sub.F] = 0.09, and [[mu].sub.F] = 0.009.
Caption: FIGURE 2: Graphs of numerical solutions of model system (1) showing the evolution with time of (a) population of infected humans ([I.sub.H]), (b) population of infected copepods ([I.sub.E]), (c) population of Guinea worm eggs in the physical water environment, and (d) population of Guinea worm larvae in the physical water environment, for different values of the infection rate of humans [[beta].sub.H]: [[beta].sub.H] = 0.1055, [[beta].sub.H] = 0.55, and [[beta].sub.H] = 0.9.
Caption: FIGURE 3: Graphs of numerical solutions of model system (1) showing the evolution with time of (a) population of infected humans ([I.sub.H]), (b) population of infected copepods ([I.sub.E]), (c) population of Guinea worm eggs in the physical water environment, and (d) population of Guinea worm larvae in the physical water environment, for different values of natural death rate of copepods [[mu].sub.E]: [[mu].sub.E] = 0.005, [[mu].sub.E] = 0.05, and [[mu].sub.E] = 0.5.
medinensis by drinking water from stagnant sources (e.g., ponds) contaminated by copepods (water fleas) that contain Guinea worm larvae. Currently, no effective drug to treat nor vaccine to prevent dracunculiasis is available, and persons who contract D.