Sporothrix spp. EVALUATION IN SOIL OF A HYPERENDENIC AREA FOR SPOROTRICHOSIS IN SOUTHERN BRAZIL

Abstract The increase in zoonotic sporotrichosis cases has become a public health problem in hyperendemic areas for the feline disease. Domestic cats involvement in this transmission and the continuous contact of these animals with soil suggest that the environment may be an essential source and/or reservoir of Sporothrix spp. Thus, the current study aimed to evaluate the presence of Sporothrix spp. in the soil of places where infected cats in Southern Brazil is present. In total, 101 soil samples were collected from the residence of cats with sporotrichosis, from regions around to these residences, and also from public places. These samples were processed using the direct plating technique being incubated at 25 °C for up to 15 days. Additionally, seventeen samples were also submitted to DNA extraction (NORGEN BIOTEK CORP® kit), PCR-specific and Nested-PCR technique. Although the presence of Sporothrix in soil has been undetected, by culture or molecular biology, this study does not reject the role of the environment in the triad of the infectious process (soil-animal-human). Thus, further studies are necessary for expanding the area of coverage, volume, type and method of sampling, and/or detection techniques.

摘要：人畜共患孢子丝菌病病例数的增加，已在该猫源孢子丝菌病的高流行区成为一项公共卫生问题。家猫参与了该疾病的传播，且这类动物与土壤存在持续接触，这提示环境可能是孢子丝菌属（Sporothrix spp.）的重要传染源和/或储存库。因此，本研究旨在检测巴西南部受感染猫所在场所土壤中的孢子丝菌属分布情况。本研究共采集101份土壤样本，采集来源包括孢子丝菌病患猫的居所、居所周边区域以及公共场所。所有样本均采用直接平板培养法处理，并在25℃条件下培养最长15天。此外，另有17份样本采用DNA提取试剂盒（NORGEN BIOTEK CORP®试剂盒）完成DNA提取，并开展特异性聚合酶链式反应（PCR）与巢式聚合酶链式反应（Nested-PCR）检测。尽管通过培养或分子生物学方法均未在土壤中检出孢子丝菌属，但本研究并未否定环境在土壤-动物-人这一传染病传播三角中的作用。因此，未来需开展进一步研究，扩大采样覆盖范围、提升样本量、优化采样类型与采样方法，并完善检测技术。