With infectious diseases increasing worldwide, the need to understand how and why disease outbreaks occur is becoming increasingly important. Looking for answers, a team of University of South Florida (USF) biologists and colleagues found broad evidence that supports the controversial ‘dilution effect hypothesis,’ which suggests that biodiversity limits outbreaks of disease among humans and wildlife.
The paper describing their research appears in a recent issue of the Proceedings of the National Academy of Sciences.
‘The dilution effect hypothesis is important because it warns that human-mediated biodiversity losses can exacerbate disease outbreaks, yet it has been contentiously debated,’ said study lead author Dr. David Civitello, postdoctoral researcher in the Department of Integrative Biology at USF.
Much of the debate about the dilution effect hypothesis has focused on whether it applies generally or only to a few select parasites. Until now, there have been no quantitative assessments to broadly support or refute it, and the lack of evidence has hampered understanding the relationship between biodiversity and disease risk.
In reaching their conclusions, the research team reviewed more than 200 assessments relating biodiversity to disease and found that the dilution effect applied broadly to many parasitic species.