Northern Arizona University researchers have concluded the spores that can cause Valley fever thrive in wet conditions.

Associate professor Bridget Barker with NAU’s Pathogen & Microbiome Institute said that’s one downfall of a wet Arizona monsoon season which just ended.

Barker said the previous scientific hypothesis was the fungus, Coccidioides, likes a hot, dry environment.  

“It turns out we were wrong, and we find the highest fungal burden actually in the wettest soils,” said Barker. “We believe that the period of drying that happens after monsoon or good winter rains is necessary for the organism to mature and for those spores to become airborne. It actually is responding to the monsoon in terms of growing prolifically with those wetter conditions and then responds to the drying conditions by forming those spore structures.”  

Dry spores can infect the lungs when inhaled and the infection can be fatal if it reaches the brain untreated.