Formenti Nicoletta, Gaffuri Alessandra, Trogu Tiziana, Viganò Roberto, Ferrari Nicola, Lanfranchi Paolo
Department of Veterinary Sciences and Public Health, Università degli Studi di Milano, via Celoria 10, 20133, Milan, Italy.
Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna "Bruno Ubertini" (IZSLER), via Rovelli 53, I-24100, Bergamo, Italy.
Parasitol Res. 2016 May;115(5):2115-20. doi: 10.1007/s00436-016-4981-x. Epub 2016 Mar 10.
The complex life cycle of Toxoplasma gondii involves many animal species, raising zoonotic, economic, and conservation issues. This complexity is reflected in the molecular structure of T. gondii, whose different genotypes differ in pathogenicity. Among the intermediate hosts of T. gondii, wild ungulates may be a source of human infection. Despite intense hunting activity and the consumption of raw or undercooked meat, little information is available on the spread of T. gondii and the distribution of its genotypes in these species, including the alpine chamois (Rupicapra r. rupicapra). Ninety-three sera and 50 brain tissues from chamois were sampled (1) to investigate the spread of T. gondii with serological and molecular analyses, and (2) to genotype the strains with a restriction fragment length polymorphism analysis of the SAG2 locus. The prevalence of T. gondii was low on both serological (3.2 %) and molecular (2 %) analyses, and infections were concentrated in individuals >1 year old. These findings demonstrate the sporadic presence of the protozoan in this species on consistent diagnostic tests. Horizontal transmission seems to be the main route of infection, and cats are the only definitive host in the study area. This prevalence suggests that the environment of the chamois is less contaminated with oocysts than environments close to human settlements. The SAG2 type II genotype was detected in this species for the first time. Although this genotype is predominant in human toxoplasmosis, these results suggest that the chamois is a minor source of human infection.
刚地弓形虫复杂的生命周期涉及许多动物物种，引发了人畜共患病、经济和保护等问题。这种复杂性体现在刚地弓形虫的分子结构上，其不同基因型在致病性方面存在差异。在刚地弓形虫的中间宿主中，野生有蹄类动物可能是人类感染的来源。尽管存在高强度的狩猎活动以及生肉或未煮熟肉类的消费，但关于刚地弓形虫在这些物种中的传播及其基因型分布的信息却很少，其中包括高山瞪羚（岩羚羊指名亚种）。采集了93份瞪羚血清和50份脑组织样本，（1）通过血清学和分子分析来研究刚地弓形虫的传播情况，（2）通过对SAG2基因座进行限制性片段长度多态性分析来对菌株进行基因分型。在血清学分析（3.2%）和分子分析（2%）中，刚地弓形虫的感染率都很低，且感染集中在1岁以上的个体。这些发现表明，在一致的诊断测试中，该原生动物在这个物种中呈散发性存在。水平传播似乎是主要的感染途径，而猫是研究区域内唯一的终末宿主。这种感染率表明，与靠近人类住区的环境相比，瞪羚所处的环境受卵囊污染的程度较低。首次在该物种中检测到SAG2 II型基因型。尽管这种基因型在人类弓形虫病中占主导地位，但这些结果表明瞪羚是人类感染的次要来源。
