Pathogen and Microbiome Institute, Northern Arizona University, Applied Research and Development Building, 1298 S Knoles Drive, Flagstaff, AZ, 86011-4073, USA.
School of Medicine, University of Brasília, Brasília, DF, Brazil.
Mycopathologia. 2020 Feb;185(1):145-159. doi: 10.1007/s11046-019-00391-2. Epub 2019 Oct 4.
The lack of knowledge regarding the ecology of Coccidioides spp. makes both modeling the potential for disease outbreaks and predicting the distribution of the organism in the environment challenging. No single ecological parameter explains the biogeography of the pathogen. Previous investigations suggest an association with desert mammals, but these results should be confirmed with modern molecular techniques. Therefore, we used molecular tools to analyze soils associated with animal activity (i.e., burrows) to better define the ecology and biogeography of Coccidioides spp. in Arizona. Soils were collected from locations predicted to have favorable habitat outside of the established endemic regions to better understand the ecological niche of the organism in this state. Our central hypothesis is that soils taken from within animal burrows will have a higher abundance of Coccidioides spp. when compared to soils not directly associated with animal burrows. Our results show that there is a positive relationship with Coccidioides spp. and animal burrows. The organism was detected in two locations in northern Arizona at sites not known previously to harbor the fungus. Moreover, this fungus is able to grow on keratinized tissues (i.e., horse hair). These results provide additional evidence that there is a relationship between Coccidioides spp. and desert animals, which sheds new light on Coccidioides' ecological niche. These results also provide evidence that the geographic range of the organism may be larger than previously thought, and the concept of endemicity should be reevaluated for Coccidioides.
由于对粗球抱子菌属生态学缺乏了解，使得疾病爆发的潜在可能性建模和预测该生物在环境中的分布都具有挑战性。没有单一的生态参数可以解释病原体的生物地理学。先前的研究表明其与沙漠哺乳动物有关，但这些结果应用现代分子技术加以证实。因此，我们使用分子工具来分析与动物活动（即洞穴）相关的土壤，以更好地定义亚利桑那州粗球抱子菌属的生态学和生物地理学。从预测在已建立的地方病流行地区之外具有有利栖息地的位置采集土壤，以更好地了解该生物在该州的生态位。我们的中心假设是，与动物洞穴直接相关的土壤相比，从动物洞穴中采集的土壤中粗球抱子菌属的丰度更高。我们的结果表明，粗球抱子菌属与动物洞穴之间存在正相关关系。该生物在亚利桑那州北部的两个地点被检测到，而这些地点以前并不知道存在这种真菌。此外，该真菌能够在角蛋白组织（即马毛）上生长。这些结果提供了更多证据表明粗球抱子菌属与沙漠动物之间存在关系，这为粗球抱子菌属的生态位提供了新的认识。这些结果还表明，该生物的地理范围可能比以前认为的要大，应该重新评估粗球抱子菌属的地方病概念。
