According to a study, climate change is increasing the spread of many pathogens. A team of researchers from the University of Hawaii concludes in a review that 58 percent of the diseases caused by pathogens can be made worse by climate change.
This happens through the warming itself, but also through extreme weather phenomena such as droughts, floods or heat waves. The study in the journal "Nature Climate Change" was based on a list of 375 diseases worldwide that are caused by pathogens such as viruses, bacteria, plant pollen or fungi.
In their literature research, the researchers found over 1000 individual pathways, each of which promoted a pathogen as a result of climate change. For example, heat (160 individual diseases) or floods (121) could promote the spread of pathogens such as bacteria or mosquitoes, ticks and other disease carriers. Extreme weather can weaken the human immune system through stress or malnutrition and increase susceptibility to infections.
Co-author Tristan McKenzie of the University of Hawaii highlights vector-borne diseases (such as mosquitoes or ticks). "We found over 100 diseases that were amplified by this transmission route," McKenzie said when asked.
Lothar Wieler: "Return of malaria possible"
The President of the Robert Koch Institute (RKI), Lothar Wieler, had previously called for exotic diseases to be considered in this country. "Climate change is leading to an expansion of the habitats for mosquitoes and ticks in Germany," Wieler told the newspapers of the Funke media group. "Many mosquito and tick species can transmit viral, bacterial and parasitic pathogens," says Wieler. These could be zika or dengue viruses, for example. "A return of malaria caused by Plasmodium is also possible." It is therefore an important concern of the RKI to sensitize the medical profession to these diseases.
Renke Lühken, ecologist at the Bernhard Nocht Institute for Tropical Medicine in Hamburg, is also concerned about the development. "In general, higher temperatures and changed precipitation regimes increase the risk of pathogens transmitted by so-called vectors - such as mosquitoes or ticks. This is worrying because only a few of these pathogens have approved vaccines," says the expert, who was not involved in the article was involved.
"In Germany and Europe we are already observing the impact of climate change-related events on pathogens. Vector-borne pathogens also play a major role here," said Lühken. "Exotic mosquito species such as the Asian tiger mosquito are establishing themselves in large parts of Europe. The Asian tiger mosquito is particularly responsible for outbreaks of the chikungunya virus and dengue virus in the Mediterranean region."
Greenhouse gas emissions must be reduced
The University of Hawaii research team sees the need for "aggressive measures to limit greenhouse gas emissions" given the looming risks from climate change-fueled diseases.
Lühken shares this assessment. "The study impressively shows that many different transmission paths have an impact on various pathogens," says the expert. "This complexity makes social adaptation very difficult, so that reducing greenhouse gas emissions must continue to be the most important countermeasure."
