Dipartimento di Patologia e Clinica Veterinaria, Facoltà di Medicina Veterinaria, Università degli Studi di Sassari, Via Vienna, Sassari, Italy.
Zoonoses Public Health. 2010 Dec;57(7-8):e102-8. doi: 10.1111/j.1863-2378.2009.01292.x.
An outbreak of toxoplasmosis occurring in a typical farm of 524 ovines was monitored for 1 year after the occurrence of 31 abortions. Abortion events involved 7.2% of 430 pregnant sheep. Presence of antibodies to Toxoplasma gondii in sheep sera was investigated by the indirect fluorescence antibody test (IFAT). A total of 422 ewes were bled four times during the year, and an epidemiological analysis was performed on all serology data collected in this subgroup. The prevalence of IgG positives ranged from 31.52% (133/422) at the first sampling to 62.56% (264/422) at the fourth sampling. Incidence of IgG antibodies was 38.75% at the second sampling, 14.92% at the third and 29.28% at the fourth sampling. At the beginning of the study, prevalence was 70.7% in primiparous sheep and 20.9% in sheep older than 5 years; at the third sampling, prevalence was stable at 70% in pluriparous sheep. The mean prevalence of IgM antibodies was 14.87%. A total of 147 out of all 524 ovines of the flock tested positive for IgM in more than one sampling. After an initial positivity, 60 sheep tested negative for IgG at the following serological controls (4 between the first and the second sampling, 30 between the second and the third and 28 between the third and the fourth sampling). One stray cat was positive for IgG, with a titre of 1 : 320. Moreover, one of the farmers was also positive, with a titre of 1 : 160 for IgG. A positive PCR result for T. gondii DNA was also observed in aliquots of grain and pellets taken from feed stocks amassed inside the sheds without protection, suggesting that an adequate management of the farm might be useful, if not essential, for controlling T. gondii outbreaks in ovine flocks.
在发生 31 例流产后，对一个典型的 524 只绵羊养殖场中的弓形虫病暴发进行了为期 1 年的监测。流产事件涉及 430 只怀孕绵羊的 7.2%。通过间接荧光抗体试验（IFAT）检测绵羊血清中的弓形虫抗体。在这一年中，共有 422 只母羊被采血 4 次，并对该亚组收集的所有血清学数据进行了流行病学分析。在第一次采样时，IgG 阳性率为 31.52%（133/422），在第四次采样时达到 62.56%（264/422）。第二次采样时 IgG 抗体的发病率为 38.75%，第三次和第四次采样时分别为 14.92%和 29.28%。在研究开始时，初产绵羊的患病率为 70.7%，5 岁以上绵羊的患病率为 20.9%；在第三次采样时，多产绵羊的患病率稳定在 70%。IgM 抗体的平均阳性率为 14.87%。在羊群的 524 只绵羊中，共有 147 只在多次采样中检测到 IgM 阳性。在初次阳性后，60 只绵羊在随后的血清学对照中 IgG 检测为阴性（第一次和第二次采样之间 4 只，第二次和第三次采样之间 30 只，第三次和第四次采样之间 28 只）。一只流浪猫 IgG 阳性，滴度为 1：320。此外，其中一名农民的 IgG 也呈阳性，滴度为 1：160。从没有保护措施的棚内饲料中采集的谷物和颗粒样本的 T. gondii DNA 的 PCR 结果也呈阳性，这表明如果不是绝对必要，对农场进行适当的管理可能有助于控制绵羊群中的弓形虫病暴发。
