New areas at risk
Even though the overall infection is predicted to decline in Africa, the study also identifies some areas where the disease could spread. Senior researcher Thomas Kristensen from the Department of Veterinary Disease Biology explains:
"Our models are not designed to pinpoint changes on a local scale but they provide an overall picture of a decline in areas suitable for the parasite in West and Central Africa, while it may be able to establish itself in new areas especially in Africa's southern regions."
In addition, climate change will affect the host snails differently and one of the studied species actually stands to benefit from the changes. The study underlines that it is essential to include biological knowledge of different host species in the models to gain robust future scenarios for the spread of diseases.
Climate is not everything
The research also shows, however, that climate is not necessarily the most important factor for the spread of diseases such as snail fever. Natural and human-induced changes of the snails' habitats, which are difficult to predict, may also play a very important role.
"Over results highlights that especially anthropogenic environmental change - in combination with climatic factors - is crucial for the present distribution of host snails in Africa", concludes Anna -Sofie Stensgaard.
This is consistent with other studies showing that man-made changes in the environment such as the damming of rivers, irrigation of fields and construction of large water reservoirs can create new habitats for the snails, which could in turn increase the risk of infection.
The research was conducted in collaboration with researchers from Switzerland, Zambia, Uganda and Cameroon.
|Contact: Post doc Anna-Sofie Stensgaard|
University of Copenhagen