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Table 1 Definitions and values for model parameters

From: Evaluating long-term effectiveness of sleeping sickness control measures in Guinea

Parameter Definition Value Reference
V/H Number of tsetse flies (V) per human (H) 17 [15]
L/H Number of NHA (L) per human (H) 1/6 [15]
H Population size of Boffa East Mainland in 2008 14,500 Unpublished data
B V Tsetse constant birth rate 0.05/day [15]
1/η V Duration of pupae stage in tsetse 20 days [18]
\( {\mu}_{V_0} \) Tsetse death rate without competition 0.030/day [15]
\( {\mu}_{V_1} \) Death rate competition parameter 0.0002 Assumed
1/σ V Susceptibility period in tsetse 1 day [15]
a Tsetse biting rate 0.333/day [15]
β VH Probability of tsetse bite on human See Table 2 Estimated
β VL Probability of tsetse bite on NHA min(1-β VH ,0.71) [25]
1/τ V Incubation period in tsetse 25 days [15]
μ H Human constant death rate 4.66e-05 /day [34]
β H Transmission probability from tsetse to humans See Table 2 Estimated
1/τ H Incubation period in humans 12 days [15]
1/γ H1 Stage I infectious period without treatment 526 days [35]
1/γ H2 Stage II infectious period without treatment 252 days [36]
1/δ H Immune period in humans after treatment 50 days [15]
β L Transmission probability from tsetse to NHA See Table 2 Estimated
β V Transmission probability from humans/NHA to tsetse 0.2 [2, 15]
1/τ L Incubation period in NHA 12 days [15]
1/γ L Infectious period in NHA 50 days [15]
1/δ L Immune period in NHA 50 days [15]
ϕ Coverage of active surveillance Varies -
ρ Probability that a HAT patients gets a positive CATT and then a positive antibody/Trypanolysis test 0.87 [1]
ε 1 Efficacy of stage I treatment (pentamidine) 0.94 [37]
ε 2 Efficacy of stage II treatment (nifurtimox-eflornithine) 0.965 [38]
ζ Treatment seeking rate of stage II patients See Table 2 Estimated
p Probability of death due to stage II treatment failure (nifurtimox-eflornithine) 0.007 [38]