headerphoto

Malaria

pool Malaria has distinct environmental drivers. Rainfall defines the transmission season by provided breeding sites for the mosquitoes that are the vectors of the disease, while temperature impacts both the vector larva and adult lifecycles. Many other environmental factors play a role, from soil type and terrain topography which affect the surface hydrology, as well as the land cover type. Socio-economic factors should not be neglected. Interventions can depress transmission or eradicate it altogether in a region, but population migration can reintroduce the disease. Understanding what drives malaria transmission in this complex web of factors could be aided by accurate models of the disease transmission that operate over regional scales.


VECTRI Malaria Model

Addis Ababa school VECTRI is a mathematic dynamical model for malaria transmission that accounts for the impact of climate variability and population. It was written in the early period of 2011 and officially launched at the second workshop for East Africa Climate and impacts at the university of Addis Ababa in November 2011. The underlying aim of the model is to provide a research tool to understand what drives malaria transmission that can be applied on a regional scale but at spatial resolutions of 10km or less. THE DOCUMENTATION IS CURRENTLY BEING UPDATED AND MIGRATED TO GITHUB.IO - DURING THIS PROCESS THE ONLINE DOCUMENTATION IS FROZEN AND SOMEWHAT OUT OF DATE. PLEASE HAVE PATIENCE AND WE AIM TO RELEASE THE NEW PLATFORM IN SUMMER 2023.


What is new in VECTRI?

Vectri run VECTRI attempts to incorporate a simple but physically based treatment of surface hydrology, and more importantly it accounts for the population density when calculating biting rates and transmission probabilities. This is important, since it allows the model to represent the difference in transmission rates between rural and peri-urban locations. Moreover, the link to population means that the model can be actively developed to incorporate immunity, migration, socioeconomic status, urbanisation and interventions. It does this in a framework that allows regional or even continental-wide simulations.

NEWS

20/12/2021: VECTRI v1.9 released!!!
NEW features in VECTRI v1.9
This upgrade to the code mostly focuses on improvements to the hydrological scheme. The manual will be upgraded soon to outline these in more detail.
  • Ability to read in externally generated pond fraction from a full hydrological modelling scheme
  • New map of permanent breeding sites using pond edge fraction derived from Sentinal 2 data (20m/150m resolution Africa/global, aggregated to 5km)
  • Correction and relaunch of the revised Asare pond scheme which allows for non-linear runoff and overflow and is validated against in situ observations and high resolution modelling in Ghana and Niger (see Asare et al. 2016a/b)
  • Maps of soil texture used to allow spatially varying infiltration rates according to clay/silt/sand proportions
  • New -v command line option to pass modified paramters to code (avoiding the need to place options in the vectri.options file).

  • Version 1.8.0/1.8.1
    Jan 2020: Diffusion of vectors between gridcells added.
    May 2019, Version 1.7.0 has now been released (May 2019) which introduces a massively simplified interface to make it much easier to run the code with gridded data. The model no longer accepts text file input, only netcdf input is possible (a grib interface is currently under testing). A new (and slowly improving) manual is also available.

    Did you know?

    VECTRI is being used in a new project in collaboration with IAEA that will use machine learning to derive efficient strategies for vector release in the Steralized insect technique (SIT) for vector control, accounting for climate seasonality and year to year variability.
    VECTRI downloads: