Temperature suitability for Plasmodium vivax transmission was calculated using a dynamic biological model and spatial time series temperature data. The temperature data used was a time series across an average year (1950-2000) for every approx. 1km2.
The biological model incorporates the impact of temperature on 1) vector lifespan and 2) the duration of P. vivax sporogeny. The index of suitability is a relative, not absolute, measure of the effect of temperature on vectorial capacity and reproductive number. All other factors being equal, it is a relative measure of the number of infectious mosquitoes in an environment defined by the temperature profile at that location, given a constant adult mosquito recruitment rate. Index values of 0 indicate that no vectors survive long enough to support transmission and the environment is therefore unsuitable all year round (shaded grey on the map).
Full details are provided in the paper below.