a 5 x number of nodes matrix, each row represents the following for all the nodes:
Row 1: number of suspectible people, i.e., population excpect infected and recovered for each node;
Row 2: number of infected people;
Row 3: number of recovered people;
Row 4: bacteria concentration in equilibrium with infected individuals;
Row 2: number of infected people, but representing cumulative cases
Arguments
POP_node
vector, length represents number of cities/nodes; vector represents
population at each node
sigma
symptomatic ratio, i.e., fraction of infected people that develop symptoms and are infective.
(The remaining fraction enters directly the recovered compartment.)
mu_B
death rate of V.cholerae in the aquatic environment (day^-1)
theta
contamination rate
node_in
index/indices for initial infected node(s)
in_prevalence
initial prevalence of symptomatic infected in a node, default is 0.1%