Grupo de Estudio en Parasitología y Micología Molecular (GEPAMOL), Centro de Investigaciones Biomédicas, Facultad Ciencias de la Salud, Universidad del Quindío, 630004 Armenia, Colombia.
Grupo de Biodiversidad y Conservación Genética, Instituto de Genética, Universidad Nacional de Colombia, 111321 Bogotá, Colombia.
Parasite. 2020;27:25. doi: 10.1051/parasite/2020023. Epub 2020 Apr 17.
The high prevalence of Toxoplasma gondii in the human population in Colombia has been linked to the existence of a high density of urban stray cats, exposing the whole population to a high density of oocysts. The goal of this study was to determine the DNA prevalence of T. gondii by conventional PCR and to phylogenetically analyze ROP18 sequences from positive samples in domestic cat (Felis catus) fecal samples in the city of Armenia, Quindío. Fecal samples from 140 cats were collected from 10 districts around the city. Samples were concentrated using Ritchie's method and analyzed through optical microscopy. Concentrates were used for DNA extraction followed by nested PCR amplification for T. gondii gene B1. PCR for ROP18 was performed on all B1 positive samples; the ROP18 sequences obtained were related to the Archetype I Brazilian and Chinese strains. No oocysts were detected by optical microscopy; however, 17.8% (25/140) B1 and 24% (6/25) ROP18 PCR-positive samples were detected. Phylogenetic analyses showed that isolates clustered into a single group. We assessed whether associations existed between T. gondii positive fecal samples and survey variables such as cat healthcare and socioeconomic characteristics of owners, but no statistically significant associations were found. The presence of T. gondii in cat feces is an important factor contributing to the high prevalence in the human population of this city.
在哥伦比亚，人类群体中刚地弓形虫的高流行率与城市流浪猫的高密度存在有关，这使整个人群暴露于高密度的卵囊之下。本研究的目的是通过常规 PCR 确定 T. gondii 的 DNA 流行率，并对来自亚美尼亚市（昆迪纳马卡省）家猫粪便中阳性样本的 ROP18 序列进行系统发育分析。从该市周围 10 个区采集了 140 只猫的粪便样本。使用 Ritchie 法对样本进行浓缩，并通过光学显微镜进行分析。对浓缩物进行 DNA 提取，然后对 T. gondii 基因 B1 进行巢式 PCR 扩增。对所有 B1 阳性样本进行 ROP18 PCR；获得的 ROP18 序列与巴西和中国原型 I 株相关。光学显微镜未检测到卵囊；然而，检测到 17.8%（25/140）B1 和 24%（6/25）ROP18 PCR 阳性样本。系统发育分析显示，分离株聚集在单个组中。我们评估了 T. gondii 阳性粪便样本与调查变量（如猫的医疗保健和主人的社会经济特征）之间是否存在关联，但未发现统计学上显著的关联。猫粪便中存在刚地弓形虫是导致该市人类群体高流行率的重要因素。
