Arias María Sol, Moreno Virginia, Sarasa Mathieu, Paz-Silva Adolfo, Sánchez-Andrade Rita, Morrondo Patrocinio, Díez-Baños Pablo, Granados José E, Sánchez Antonio, Pérez Jesús M
Departamento de Parasitología y Enfermedades Parasitarias, Facultad de Veterinaria, Universidad de Santiago de Compostela, Campus Universitario, s.n., E-27002, Lugo, Spain;
J Parasitol. 2014 Apr;100(2):235-8. doi: 10.1645/13-190.1. Epub 2013 Dec 3.
Oestrosis is one of the most prevalent parasitosis affecting the Iberian ibex, Capra pyrenaica . To date, both the diagnosis of oestrosis and the determination of the intensity of parasitism require the use of invasive methods (necropsy), which necessarily limit research possibilities. We analyzed the immune humoral response (IgM and IgG) against Oestrus ovis L. excretory/secretory larval antigens in 32 sera taken from Iberian ibex from the Sierra Nevada Natural Space (southern Spain). Three antigens were collected: L1OES (from L1 larvae), L2OES (L2), and L3OES (L3). Necropsy was considered as the gold standard. The percentage of ibexes harboring Oestrus spp. larvae was 88%, the mean intensity of parasitism being 16.96 ± 14.96 larvae per parasitized host (range: 2-52). In our sample, first-instar larvae (L1) were found in 9% of ibexes, while 69% of hosts carried L2 larvae and 88% L3 larvae. Positive correlations between L1 and L2 numbers, and between L2 and L3 numbers were detected. The best results with the immunoenzymatic assay were obtained using IgG antibodies against the L1OES antigens (specificity = 89%; sensitivity = 100%; positive predictive value = 100%; negative predictive value = 57%). The IgG seroprevalence against L1OES was 78%. Thus, the analysis of IgG antibodies against antigens collected from L1 O. ovis larvae would seem to be a noninvasive method for reliably diagnosing oestrosis in naturally infested Iberian ibex. Nevertheless, additional immunological and methodological advances are still required because false positive and false negative results still represent a non-negligible part of the results of the ELISA tests.
狂蝇蛆病是影响西班牙伊比利亚野山羊（Capra pyrenaica）的最常见寄生虫病之一。迄今为止，狂蝇蛆病的诊断和寄生虫感染强度的测定都需要使用侵入性方法（尸检），这必然限制了研究的可能性。我们分析了取自西班牙南部内华达山脉自然保护区的32份伊比利亚野山羊血清中针对羊狂蝇（Oestrus ovis L.）排泄/分泌幼虫抗原的免疫体液反应（IgM和IgG）。收集了三种抗原：L1OES（来自L1幼虫）、L2OES（L2）和L3OES（L3）。尸检被视为金标准。感染狂蝇属幼虫的野山羊比例为88%，每个受感染宿主的平均寄生虫感染强度为16.96±14.96条幼虫（范围：2 - 52条）。在我们的样本中，9%的野山羊体内发现了一龄幼虫（L1），而69%的宿主携带L2幼虫，88%携带L3幼虫。检测到L1和L2数量之间以及L2和L3数量之间存在正相关。使用针对L1OES抗原的IgG抗体进行免疫酶测定获得了最佳结果（特异性 = 89%；敏感性 = 100%；阳性预测值 = 100%；阴性预测值 = 57%）。针对L1OES的IgG血清阳性率为78%。因此，分析针对L1羊狂蝇幼虫收集的抗原的IgG抗体似乎是一种用于可靠诊断自然感染伊比利亚野山羊狂蝇蛆病的非侵入性方法。然而，仍需要进一步的免疫学和方法学进展，因为假阳性和假阴性结果在ELISA检测结果中仍占不可忽视的比例。
