Microbial responses to climate change and potential impacts to public health

Background/Question/Methods

Global climate change is projected to increase the spread of soil-borne infectious diseases due to persistent stressful environmental conditions, such as drought and soil disturbances (e.g., dust storms). Because pathogenic microbes are good at tolerating stress, they may thrive under environmental stressful conditions compared to other non-pathogenic microbes. This represents a threat to public health because many soil-borne pathogens, particularly spore-producing fungi, have small aerodynamic spores which are easily dispersed. The overarching goal of this project was to determine if dried and disturbed soils represent a threat to public health by examining if global climate change favors the growth of pathogenic soil fungi. Therefore, we sampled soils from a global change experiment where soils are experimentally dried and disturbed as predicted for the Southwest of the USA in the wake of global climate change. We hypothesized that pathogenic soil fungi increase in abundance under treatments compared to control.

Results/Conclusions

We extracted DNA from control and treatment soils. Within each plot, we collected samples from two different micro-sites: under vegetation and inter space (i.e., bare soil without vegetation); nutrients, moisture, and temperature are vastly different between micro-sites and can consequently affect the community of microbes. We carried out ITS metabarcoding to identify fungi at the taxonomical level and at the functional level. Understanding the complex causal relationship between global climate change, changes in the fungal community, and potential public health threats, will allow to better predict future infectious disease hot spots and outbreaks. Moreover, our work is providing information for policy makers on the public health threat potential that climate change has on soil fungal communities in the Southwest of the USA.