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# Table 2 Parameterisation for vector-borne disease models

Definition Plasmodium falciparum Trypanosoma cruzi Borrelia burgdorferi
b i Transmission coefficient (vectors→hosts) = bite rate x transmission probability 0.1 = 1/3 × 0.3 (humans) [42]; 0 (non-humans) 2 × 10-5 = ¼ × 8 × 10-5 (humans) [43, 44]; 2.5 × 10-4 = ¼ × 0.001 (non-humans) [45] $$0.003=\frac{1}{365}\kern0.5em \times \kern0.5em 1.0\ \left(\mathrm{humans}\ \mathrm{and}\ \mathrm{n}\mathrm{o}\mathrm{n}\hbox{-} \mathrm{humans}\right)$$ [46]
b Vi Transmission coefficient (hosts→vectors) = bite rate x transmission probability $$0.007=\raisebox{1ex}{1}\!\left/ \!\raisebox{-1ex}{3}\right.\kern0.5em \times \kern0.5em 0.02\kern0.5em \left(\mathrm{humans}\right)$$ [47]; $$0\kern0.5em \left(\mathrm{n}\mathrm{o}\mathrm{n}{\textstyle \hbox{-}}\mathrm{humans}\right)$$ 0.015 = ½ × 0.03 (humans); 0.25 = ½ × 0.49 (non-humans) [48] $$0\ \left(\mathrm{humans}\right);$$ $$0.003\kern0.5em =\kern0.5em \frac{1}{365}\kern0.5em \times \kern0.5em 1.0\ \left(\mathrm{n}\mathrm{o}\mathrm{n}\hbox{-} \mathrm{humans}\right)$$ [46]
γ Recovery rate (no immunity) 0 (humans and non-humans) 0 (humans and non-humans) 1/28 (humans)a; 0 (non-humans) [31]
ε Clearance rate of symptomatic infection 1/200 (humans) [49]; 0 (non-humans) 0 (humans and non-humans) 0 (humans and non-humans)
κ Clearance rate of asymptomatic infection 1/200 (humans) [49]; 0 (non-humans) 0 (humans and non-humans) 0 (humans and non-humans)
π Asymptomatic primary infection rate 0 (humans and non-humans) 1/40 (humans and non-humans) [50, 51] 0 (humans); 1/28 (non-humans) [31]
θ Asymptomatic secondary infection rate 0.5 (assumed for humans); 0 (non-humans) 0 (humans and non-humans) 0 (humans and non-humans)
τ Full susceptibility reversion rate 1/1000 (humans) [52]; 0 (non-humans) 0 (humans and non-humans) 0 (humans and non-humans)
μ Birth (or maturation) and death rate of vectors (i.e. stable population) 1/10 [53] 1/365 [54] 1/365 [55]
σ Adjustment factor for asymptomatic transmissibility to vector 0.25 (humans) [56]; 0 (non-humans) ≈0 humans [30];
≈1 non-humans [57]b
0 (humans);
≈1 (non-humans)
ζ Rate of parasite development within vector 1/10 [58] 1/10 [59] 1/365 [60]c
1. aClassically, Lyme disease infection dynamics are of an SIS form whereby the pathogen is assumed to be cleared by the host’s immune system. However, Nadelman & Wormser [31] review several studies demonstrating that an SIA form is more appropriate for non-human hosts
2. bA longitudinal study of domestic dogs (a principal Chagas disease reservoir) demonstrated persistent infectiousness but it was unclear whether this was a result of repeat infections
3. cParasite development is assumed to correspond with the developmental delays between life stages of the tick (whereby the tick will take its blood-meal from a different host species)