Thanks to both Chris and Hikerdon for responding to my question. Both provided much information as well as fuel for more investigation. I ran a Google search on Coccidioides immitis finding many of the symptoms to be similar to an upper-respiratory disease I encountered in the early summer of 1989. Nine of 14 participants came down with a flu-like condition after returning from an expedition studying wild cave systems in Mexico. The symptoms: cough, chest pain, shortness of breath, fever, night sweats, and fatigue were distributed in varying qualities throughout the non-Southwest people (3 in PA, 2 in FL, 1 in NC, 1 in IN, 1 in IL, and me in MO). Three days after returning from Mexico I received a call from the wife of the Illinois caver saying he was in intensive care with an unknown condition. She said two of the three Pennsylvanians and both Floridians were in bed with flu-like symptoms. She had not called the others yet. I was not feeling very well but was not bed-ridden. In two days I was at my doctor’s office complaining of the above symptoms and getting numerous blood tests and chest x-rays. When tests came back eliminating Histoplasmosis capsultum (from breathing dried bat guano) as well as other fungal entities, such as I suspect C. immitis, my doctor was in a quandary as well as the other’s doctors (who were now in touch with each other). I was now in bed and all the other eight above mentioned were also. The Center for Disease Control and Prevention in Atlanta monitored all with no success in naming the offending culprit. To cut to the chase, I was out of work for 33 days and lost 14 pounds. Others confirmed similar lost workage and poundage. The CDC eventually said the cause was an upper respiratory viral infection to raw sewage (human and other) pumped onto the hills outside Mexico City, which dried and became airborne. Medication consisted of anti-biotics, bed rest and lots of fluids. The un-named disease seemed to run its course in four to five weeks for all involved, but I was weak and very lethargic for two more months. Surprisingly the 3 Texans and 2 Arizonians did not show any signs of the disease. All involved were in above average health and all were avid outdoors persons. As instructed we all wore bandanas over our faces when at known Histoplasmosis sites but this came from outside – in what seemed to be just dusty, high-desert conditions in Mexico. With public awareness of airborne diseases in post 9/11 America what can or should we do to help prevent attacks from natural pathogens?<br><br>To Hikerdon: I enjoyed your description of rock shelter camping. That, I think, was what I wanted to know about the fire – did the Anasazi or other cliff dwellers just build a fire or did outside wind currents and other elements (not caves) have to do with the placement? <br><br>What does “prehistoric oonflagration” mean as in: Fire scarring on the walls of the rockshelter is less common and is often the result of a prehistoric oonflagration.<br><br><br>Thanks and sorry about the long post.<br><br>Arinite7<br><br><br><br>