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Coccidioidomycosis (Valley fever), caused by Coccidioides spp., is a fungal infection endemic to semi-arid regions of the Americas. Despite 80 years of disease recognition in New Mexico, there is limited disease awareness. We incorporated clinical, epidemiological, and ecological datasets to summarize the knowledge of Valley fever in New Mexico. We analyzed 1541 human cases from 2006 to 2023. On average, 86 cases were reported each year (4.1 cases per 100,000 population per year). The highest levels of incidence were in southwestern New Mexico. American Indian or Alaska Natives in New Mexico had a 1.9 times higher incidence rate of coccidioidomycosis than White people, and among age groups, older populations in New Mexico had the highest incidence rates. We analyzed 300 soil samples near Las Cruces, New Mexico, for the presence of Coccidioides and reported the first known positive soil samples collected from the state, the majority of which were from grassland-dominated sites and from animal burrows. Sequence analyses in clinical specimens, wild animals, and soil samples confirmed that Coccidioides posadasii is the main causative species of coccidioidomycosis in New Mexico. Environmental surveillance validated that locally acquired infections could occur in, but are not limited to, Catron, Doña Ana, Sierra, and Socorro Counties. 

Defined as fungi that grow better at 25 °C than at 45 °C, thermophilic fungi were discovered more than a century ago. Nevertheless, little is known about the natural roles and distribution of these organisms. Although common in “sun-heated soils” and other natural substrates they have most often been recovered from manmade composts, and one hypothesis suggests that they evolved as decomposers in natural compost. This hypothesis suggests that propagules found outside compost have been dispersed by wind, an idea that seems nearly impossible to reconcile with their high frequency and broad distribution. In this chapter we briefly review the biology, history, and evolution of thermophilic fungi. We also present new results from ongoing efforts to map the range of habitats from which thermophilic fungi can be obtained. We have isolated thermophilic fungi over small and large spatial scales. Our surveys have focused on soil, litter, and herbivore droppings sampled from diverse ecosystems (deserts, grasslands, and forests) across eight western states, Mexico and Canada—from southern deserts to alpine ecosystems in Colorado and Montana. Our results show that thermophiles can be isolated readily from all of these substrates at nearly every latitude and elevation. We observed that the success of recovering thermophilic fungi from soil decreases with increasing latitude. During this survey, we also discovered that several species of thermophilic fungi can survive storage in soil samples for several years at −80 °C.