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，已成为猫孢子丝菌病高流行地区的公共卫生问题。家猫参与该疾病的传播，且这类动物持续与土壤接触，提示环境或为孢子丝菌属（Sporothrix spp.）的关键传染源与/或储存宿主。为此，本研究旨在检测巴西南部感染猫活动区域土壤中的孢子丝菌属。本研究共从孢子丝菌病患猫的居所、居所周边区域及公共场所采集101份土壤样本。采用直接平板接种法处理样本后，于25℃下培养至多15天。此外，使用NORGEN BIOTEK CORP®试剂盒对17份样本进行DNA提取，并开展特异性PCR及巢式PCR（Nested-PCR）检测。尽管通过培养及分子生物学方法均未检出土壤中的孢子丝菌属，但本研究并未否定环境在土壤-动物-人这一感染传播三角中的作用。因此，未来需开展进一步研究，扩大采样覆盖范围、增加样本量，优化采样类型、采样方法及检测技术。