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Table 1 Parameter values for the host and parasite (S. mansoni) populations and key vaccination parameters, used in the evaluations of the models as summarised in [31]

From: Developing a mathematical model for the evaluation of the potential impact of a partially efficacious vaccine on the transmission dynamics of Schistosoma mansoni in human communities

Variable/Parameter

Interpretation

Values

N

Host population size

–

M

Mean number of adult worms

Model dependent

L

Environmental reservoir

–

μ b

Human host death rate

1/50 yrs-1

σb

Parasite mortality rate

1/4 yrs-1 [27]

μ 2 b

Free-living larvae mortality rate

365/7 yrs-1 [27]

λ b

Egg production rate per female worm

0.14 [31]

β b

Rate of contact between human and infective stages

0.63a yrs-1 [31]

ψ

Flow of infectious material into the environment

–

k

Negative binomial clumping parameter

0.24 [34]

γ

Density dependence fecundity parameter

0.0006/female worm [34]

p

Proportion of infants vaccinated per unit of time

[0,1]

q b

Rate of mass vaccination

–

ω b

Rate of loss of vaccine-induced immunity per unit of time (vaccine duration of protection: \( \tau =\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$\omega $}\right.\Big) \)

[0,∞)

v 1

Vaccine efficacy with an effect on worm life expectancy

[0,1]

v 2

Vaccine efficacy with an effect on worm fecundity

[0,1]

v 3

Vaccine efficacy with an effect on worm establishment

[0,1]

  1. aThe value of β was estimated using the weighted average of the different age groups from [31]
  2. bPer capita rates per unit of time