Graduate College in Animal Sciences, University of Western São Paulo (UNOESTE), Rodovia Raposo Tavares km 572-Bairro Limoeiro, Presidente Prudente, São Paulo, 19050-920, Brazil.
Institute of Tropical Medicine of São Paulo, University of São Paulo, São Paulo, 05403-000, Brazil.
Parasit Vectors. 2021 May 11;14(1):250. doi: 10.1186/s13071-021-04755-w.
Toxocariasis, caused by a nematode species of the genus Toxocara, has been described as one of the most prevalent zoonotic helminthiases worldwide. Human transmission may occur by ingesting Toxocara spp. larvae from raw or undercooked meat or organs; however, no comprehensive serosurvey study has been conducted to date investigating the role of cattle as paratenic hosts. The aim of the study reported here was to assess the prevalence of anti-Toxocara spp. antibodies and associated risk factors in bovines from two slaughterhouses located in Presidente Prudente, southeastern Brazil.
Blood samples were collected and tested by indirect enzyme-linked immunosorbent assay (ELISA). Cattle farmers voluntarily responded to an epidemiologic questionnaire.
Overall, 213 of the 553 (38.5%) bovine samples were assessed as seropositive for anti-Toxocara spp. antibodies by indirect ELISA. Multivariate analysis revealed that the source of beef cattle and the presence of dogs or cats at the farm were associated with seropositivity. The use of feedlot systems was associated with lower likelihood of seropositivity.
These results indicate a high level of anti-Toxocara seropositivity in slaughterhouse cattle, with potentially contaminated meat posing an infection risk to humans. In addition, the presence of dogs and cats where the slaughtered beef cattle were raised was statistically associated with bovine seropositivity, probably due to the overlapping environment at the farm and the lack of pet deworming. The use of feedlot systems was a protective factor likely due to the absence of dog and cat contact, elevated feeding troughs that avoid contact with contaminated soil or grass, and younger age at slaughter of feedlot cattle. In summary, bovines may be used as environmental sentinels of Toxocara spp. contamination, and high seropositivity of slaughterhouse cattle may indicate a potential risk of human toxocariasis through the ingestion of raw or undercooked contaminated meat.
旋毛虫病是由旋毛线虫属的线虫种引起的，已被描述为全球最普遍的人畜共患蠕虫病之一。人类感染可能是通过摄入生的或未煮熟的肉或器官中的旋毛线虫幼虫引起的；然而，迄今为止，尚无全面的血清学调查研究来调查牛作为中间宿主的作用。本报告研究的目的是评估巴西东南部普鲁登特总统市两个屠宰场的牛群中抗旋毛线虫属抗体的流行率和相关危险因素。
采集血液样本并通过间接酶联免疫吸附试验（ELISA）进行检测。牛场主自愿回答了一份流行病学问卷。
通过间接 ELISA，553 份牛血样本中，213 份（38.5%）被评估为抗旋毛线虫属抗体阳性。多变量分析显示，肉牛的来源以及农场中是否存在狗或猫与血清阳性相关。使用育肥系统与血清阳性的可能性降低相关。
这些结果表明屠宰场牛群中存在高水平的抗旋毛线虫血清阳性，受污染的肉可能对人类造成感染风险。此外，在屠宰牛生长的地方存在狗和猫与牛的血清阳性呈统计学相关，可能是由于农场环境重叠以及宠物驱虫不足。育肥系统的使用是一个保护因素，可能是由于缺乏狗和猫的接触、抬高的饲料槽避免与受污染的土壤或草接触以及育肥牛的屠宰年龄较小。总之，牛可能被用作旋毛线虫属污染的环境哨兵，屠宰场牛的高血清阳性率可能表明通过摄入生的或未煮熟的受污染肉而导致人类旋毛虫病的潜在风险。
