SIRS: The SIRS process

class epydemic.SIRS

The Susceptible-Infected-Removed-Susceptible compartmented model of disease. Susceptible nodes are infected by infected neighbours, and recover to removed where they remain for a time before returning to susceptible models the situation in which disease exposure confers partial immunity in time, rather than full immunity (as for SIR) or no immunity ( as for SIS).

Parameters

As well as the usual SIR parameters, SIRS also includes the probability of becoming susceptible again.

SIRS.P_RESUSCEPT: Final[str] = 'epydemic.sirs.pResuscept'

Parameter for probability of losing immunity

Building the model

SIRS.build(params)

Build the SIRS model.

Parameters

params (Dict[str, Any]) – the model parameters

Event methods

There is an extra event recorded when a node returns to being susceptible.

SIRS.RESUSCEPT: Final[str] = 'epydemic.sirs.RS'

Compartment/event name for returning to susceptible.

SIRS.resuscept(t, n)

Perform a re-susceptibility event. This changes the compartment of the node from REMOVED to SUSCEPTIBLE.

Parameters

  • t (float) – the simulation time (unused)

  • n (Any) – the node