A significant dust storm, referred to as a 'fungal storm,' is projected to sweep across central and southern Arizona on Wednesday, potentially carrying fungal spores that can cause a serious lung infection. The National Weather Service has issued a blowing dust advisory for the affected regions, warning of hazardous travel conditions and urging residents to remain indoors.
The storm is expected to impact Maricopa, Pinal, Pima, and Santa Cruz counties, including metropolitan areas like Phoenix and Tucson. Wind gusts reaching up to 55 mph are anticipated between 6 p.m. and 1 a.m. ET (3 p.m. to 10 p.m. local time), significantly reducing visibility to as little as a quarter-mile. Approximately 1.5 million people are within the advisory's path.
A primary concern during such dust storms is the microscopic fungus Coccidioides, which is prevalent in the soil of Arizona and surrounding Southwest states. When inhaled, these fungal spores can lead to Coccidioidomycosis, commonly known as Valley fever. While most cases result in mild, flu-like symptoms, a severe infection can spread to organs and bones, potentially becoming fatal.
Officials have not definitively confirmed the presence of Coccidioides spores in the approaching storm. However, the Centers for Disease Control and Prevention (CDC) notes that the fungus is widespread throughout Arizona and neighboring states. The CDC estimates that between 15% and 30% of all pneumonia cases in the Phoenix and Tucson areas are attributed to Valley fever.
Authorities are emphasizing safety precautions for both residents and travelers. The NWS advises individuals with respiratory issues to prepare to stay indoors until the storm subsides. For those driving, a specific safety protocol, "Pull Aside, Stay Alive," is recommended: if encountering blowing dust, drivers should pull over as far as possible, put their vehicle in park, turn off headlights, and keep their foot off the brake pedal to avoid being hit by other vehicles. Visibility can drop to near zero with little warning.