The Roman writer Vitruvius wrote of an unhealthy wind blowing off the city’s marshlands, bringing sickness. While this ancient miasmal theory of infection was superseded by germ theory, researchers have found that dust storms really can spread pathogens.
Scientists from George Mason University, Virginia, are studying dust storms in the south-western US and their connection with Valley fever, a fungal disease that kills hundreds of people every year.
The team developed a low-cost sampling tool: a cake tin filled with marbles, left outside in an affected area. Dust deposited by the storm collects in the bottom of the tin, rather than being blown away on the wind. The accumulated dust samples are tested for DNA from the Coccidioides fungal spores that cause Valley fever, allowing researchers to map their spread across the region.
The team are combining their data with information from Nasa’s Moderate Resolution Imaging Spectroradiometer (Modis) satellite sensors. Modis is able to measure soil moisture, so can help map where conditions are best for fungal growth. It is also able to track the progress of dust storms, and gather data on their changing distribution.
The work will refine the Sand and Dust Storm Warning Advisory and Assessment System to help forecast where risk is greatest for vulnerable people.