The EIR computed by Transmission is a measure of local risk: it is the expected number of infected bites, per person, and it is computed for every population stratum. The exposure module handles two aspects of exposure: travel and environmental heterogeneity. Exposure transforms the EIR into the FoI
Compute the force of infection (FoI) or attack rates (AR) as a function of the local daily entomological inoculation rate (dEIR), immunity, and exposure to malaria while traveling.
(Environmental Heterogeneity)environmental_heterogeneity
While EIR is an expected value, the expected value can have a distribution in a human population stratum. For example, if the expectation has a Gamma distribution, then the expected number of bites per person would be negatively binomially distributed.