Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Snail fever expected to decline in Africa due to climate change

13.12.2013
Research The dangerous parasite Schistosoma mansoni that causes snail fever in humans could become significantly less common in the future a new international study led by researchers from the University of Copenhagen predicts.
The results are surprising because they contradict the general assumption that climate change leads to greater geographical spread of diseases. The explanation is that the parasite’s host snails stand to lose suitable habitat due to climate change.

“Our research shows that the expected effects of climate change will lead to a reduction in suitable habitats for four out of five species of host snails for the parasite. According to our models, several areas will become too hot for the snails in the future and new precipitation patterns will affect the freshwater areas where they live”, says postdoc Anna -Sofie Stensgaard from the Danish National Research Foundation Center for Macroecology, Evolution and Climate at the University of Copenhagen.

Several of the freshwater snails acting as intermediate host for the schistosomiasis parasite, are predicted to have fewer climatically suitable habitat areas in the future. Photo: Henry Madsen, Department of Veterinary Disease Biology.

Schistosomiasis is an infectious disease caused by parasitic flatworms of the genus Schistosoma.

They infect humans by penetrating the skin when in contact with water. They spread in freshwater areas such as rivers and lakes where fresh water snails act as intermediate host for the parasite's larvae.

Therefore, the snails’ habitats are of great importance for the spread of the disease.

Up to 19 % reduction in infectious areas

The researchers modeled the changes in snail habitat from today to 2080 under various climate change scenarios, and what that will mean for the spread of the parasite. The forecasts show up to 19 % reduction in the total geographical area of infection risk in Africa, as the geographical distribution of the main host snail will be reduced significantly.

“Our results are consistent with the scientific view that climate change leads to lower biodiversity, but not that climate change necessarily leads to a greater spread of diseases”, Anna -Sofie Stensgaard explains about the study that has just been published in the scientific journal Acta Tropica.

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.

Humans are infected with schistosomiasis in freshwater areas like these, where freshwater snails act as intermediate hosts for the parasite. Photo Henry Madsen, Department of Veterinary Disease Biology. Download free press photo.

“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, mobile: +45 26297650
Senior researcher Thomas Kristensen, mobile: +45 40503674
Communications officer Elisabeth Wulffeld, mobile: +45 21179140

Anna-Sofie Stensgaard | EurekAlert!
Further information:
http://www.ku.dk

More articles from Health and Medicine:

nachricht Unique brain 'fingerprint' can predict drug effectiveness
11.07.2018 | McGill University

nachricht Direct conversion of non-neuronal cells into nerve cells
03.07.2018 | Universitätsmedizin der Johannes Gutenberg-Universität Mainz

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Subaru Telescope helps pinpoint origin of ultra-high energy neutrino

16.07.2018 | Physics and Astronomy

Barium ruthenate: A high-yield, easy-to-handle perovskite catalyst for the oxidation of sulfides

16.07.2018 | Life Sciences

New research calculates capacity of North American forests to sequester carbon

16.07.2018 | Earth Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>