Climate change could affect occurrences of diseases like bird-flu and Ebola, with environmental factors playing a larger role than previously understood in animal-to-human disease transfer, Australian researchers have found.
The team, a collaboration between The University of Queensland and Swansea University—and whose research is published in Trends in Parasitology—have been looking at how different environments provide opportunities for animal-to-human diseases, known as zoonotic diseases, to interact with and infect new host species, including humans.
These diseases are caused by pathogens—for example, viruses, bacteria or parasitic worms—that cross from animals to humans, including notorious infections like bird flu, rabies virus and Ebola.
“In the past, we’ve primarily looked at how many different types of animal species a pathogen infects—widely considered an indicator of its risk to shift between host species,” said Dr Nicholas Clark, from UQ’s School of Veterinary Science.
“This is just one factor, and we’ve found that how infected animals are related is also important.
“But importantly, our research also shows that different environments provide new opportunities for pathogens to interact with and infect new host species,” Dr Clark added.
Dr Konstans Wells, from Swansea University, led the team’s review of a growing number of research studies, demonstrating that this ‘host shifting’, where a pathogen moves between animal species, is linked to the environment.
“Now that we know that environmental conditions are key, the question is: how can we develop models to predict disease moving between species in times of global environmental change?” Dr Wells said.
“As a recent study that we published in Ecology Letters found, climate change may constrain or facilitate the spread of diseases like avian malaria, and this is just one example.
“We need to find out more information about how climate alters animal-to-human shifts, and this might help us build a new modelling framework, which could help us forecast disease spread.”