Table 3 Descriptions of state variables, parameters, and derived parameters used in the model

From: Modelling the impact of interventions on imported, introduced and indigenous malaria infections in Zanzibar, Tanzania

State variable or parameter

Description and units

State variables

Pk

Number of imported infections in patch k. Humans.

Tk

Number of introduced infections in patch k. Humans.

Dk

Number of indigenous infections in patch k. Humans.

Parameters

Nk

Total number of people in patch k (assumed to be constant). Humans.

βk

The effective malaria transmission rate from humans to other humans in patch k. Day−1.

θij

The proportion of time the average resident of patch j spends in patch i. ∑iθij = 1 j. Dimensionless.

μ

Natural infection clearance rate. Day−1.

\({\tau }_{k}^{(h)}\)

Ratio of malaria prevalence in the index household tested in RCD as compared to the general population in patch k.

\({\tau }_{k}^{(n)}\)

Ratio of malaria prevalence in neighbouring households tested in RCD as compared to the general population in patch k.

\({\nu }_{k}^{(h)}\)

Number of people tested in the index household during follow-up per index case in patch k. Dimensionless.

\({\nu }_{k}^{(n)}\)

Number of people tested in neighbouring households during follow-up per index case in patch k. Dimensionless.

ρ

Rapid diagnostic test sensitivity. Dimensionless.

η

The proportion of cases arriving at the health facility that are followed up. Dimensionless.

ξk

The daily rate at which an infected individual seeks treatment in patch k. Day−1.

Derived parameters

Sk

Number of susceptible humans in patch k, i.e. Sk = Nk − Pk − Tk − Dk. Humans.

Ik

Proportion of humans who are infectious in patch k, i.e. (Pk + Tk + Dk)/Nk. Dimensionless.

φk

Treatment rate due to RCD programme in patch k. Day−1.

ιk

Total number of cases arriving at a health facility in patch k. Humans per day.