Climatic suitability for leishmaniasis

Leishmaniasis is a climate-sensitive zoonotic disease caused by Leishmania parasites and transmitted by female Phlebotomine sandflies. Most often the disease leads to skin sores; the rarer visceral leishmaniasis affects internal organs and has a high mortality rate. 

Sandfly species thrive in regions where temperatures exceed 15°C for several months of the year. Climate change is expected to further expand the habitat of several sandfly species across Europe into more northern regions and higher altitudes.

This indicator uses a nested machine learning modelling approach to predict climatic suitability using presence/absence data for individual sandfly vector species (i.e., Phlebotomus perniciosus, P. ariasi, P. perfiliewi, P. neglectus, and P. tobbi), nine bioclimatic indicators (BIO01-06, BIO13-15), landcover data and elevation data. 

Caveats

Due to a lack of data availability, canine leishmaniasis has not been included, whilst dogs are the main reservoirs of L. infantum and are therefore considered good sentinels for human infections. Furthermore, disease data is not available at the sub-national level on a yearly basis, and it is not possible to distinguish between autochthonous and imported cases. Lastly, leishmaniasis transmission is not only linked to climatic factors, but also to specific socio-economic profiles and other risk factors. Leishmaniasis is prevalent in poorer communities and socially vulnerable populations due to higher malnutrition and lower access to healthcare.