Mohammedsalih Khalid M, Hassan Salma A, Juma Fathel-Rahman, Saeed Shamsaldeen I, Bashar Ahmed, von Samson-Himmelstjerna Georg, Krücken Jürgen
Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Robert-von-Ostertag-Str. 7, 14163, Berlin, Germany.
Veterinary Centre for Resistance Research, Freie Universität Berlin, 14163, Berlin, Germany.
Parasit Vectors. 2025 Jan 12;18(1):5. doi: 10.1186/s13071-024-06637-3.
Faecal egg counts (FECs) are essential for diagnosing helminth infections and guiding treatment decisions. For camels, no evaluations of coproscopic methods regarding precision, sensitivity and correlation between individual and pooled faecal samples are currently available.
Here, 410 camel faecal samples were collected in 2022 from South Darfur State, Sudan, and analysed to compare the semi-quantitative flotation, McMaster and Mini-FLOTAC methods in terms of precision, sensitivity, inter-rater reliability and helminth egg count correlations, as well as the effects of pooling samples. Six samples were used to assess precision for McMaster and Mini-FLOTAC, while the remaining 404 samples were evaluated for sensitivity, inter-rater reliability and egg count correlations. Of these, 80 samples were used in pooling experiments.
Six analyses of each sample (n = 6) using the McMaster and Mini-FLOTAC methods revealed no significant difference in the coefficient of variation between the two. For strongyle eggs, 48.8%, 52.7% and 68.6% were positive for McMaster, semi-quantitative flotation and Mini-FLOTAC, respectively. The sensitivity of the three methods showed only minimal improvement when three egg counts were performed on the same sample. McMaster and Mini-FLOTAC had similar sensitivity for Strongyloides spp. (3.5% frequency), while it was lower for semi-quantitative flotation at 2.5%. Mini-FLOTAC was more sensitive for Moniezia spp., detecting 7.7% of positives compared with 4.5% for semi-quantitative flotation and 2.2% for McMaster. For Trichuris spp., frequencies were 0.3% with Mini-FLOTAC, 0.7% with McMaster and 1.7% with semi-quantitative flotation. Mini-FLOTAC also detected higher strongyle eggs per gram (EPG) of faeces (mean 537.4) compared with McMaster (330.1). More samples exceeded treatment thresholds with Mini-FLOTAC, with 28.5% of animals having EPG ≥ 200 compared with 19.3% for McMaster, while 19.1% showed EPG ≥ 500 with Mini-FLOTAC compared with 12.1% with McMaster. There was no significant correlation between individual and pooled strongyle FECs, as indicated by Pearson correlation coefficients of r ≥ 0.368 (P ≥ 0.113) and Spearman correlation.
Mini-FLOTAC outperformed semi-quantitative flotation and McMaster in diagnosing helminth infections in camels, offering greater sensitivity and detecting higher EPGs, particularly for strongyles, Strongyloides spp. and Moniezia spp. Thus, treatment decisions based on Mini-FLOTAC EPGs will lead to more treatments.
粪便虫卵计数（FECs）对于诊断蠕虫感染和指导治疗决策至关重要。目前尚无关于骆驼粪便镜检方法的精密度、敏感性以及个体粪便样本与混合粪便样本之间相关性的评估。
2022年从苏丹南达尔富尔州收集了410份骆驼粪便样本，分析比较了半定量浮选法、麦克马斯特法和Mini-FLOTAC法在精密度、敏感性、评分者间可靠性、蠕虫卵计数相关性以及混合样本影响方面的差异。使用6份样本评估麦克马斯特法和Mini-FLOTAC法的精密度，其余404份样本用于评估敏感性、评分者间可靠性和虫卵计数相关性。其中80份样本用于混合实验。
使用麦克马斯特法和Mini-FLOTAC法对每个样本进行6次分析（n = 6），结果显示两者变异系数无显著差异。对于圆线虫卵，麦克马斯特法、半定量浮选法和Mini-FLOTAC法的阳性率分别为48.8%、52.7%和68.6%。对同一样本进行3次虫卵计数时，三种方法的敏感性仅略有提高。麦克马斯特法和Mini-FLOTAC法对类圆线虫属的敏感性相似（频率为3.5%），而半定量浮选法较低，为2.5%。Mini-FLOTAC法对莫尼茨绦虫属更敏感，检测到7.7%的阳性样本，而半定量浮选法为4.5%，麦克马斯特法为2.2%。对于鞭虫属，Mini-FLOTAC法的频率为0.3%，麦克马斯特法为0.7%，半定量浮选法为1.7%。与麦克马斯特法（每克粪便平均330.1个）相比，Mini-FLOTAC法检测到的每克粪便中圆线虫卵（EPG）也更多（平均537.4个）。Mini-FLOTAC法超过治疗阈值的样本更多，28.5%的动物EPG≥200，而麦克马斯特法为19.3%；19.1%的动物EPG≥500，而麦克马斯特法为12.1%。个体和混合圆线虫FECs之间无显著相关性，皮尔逊相关系数r≥0.368（P≥0.113）及斯皮尔曼相关性分析均表明如此。
在诊断骆驼蠕虫感染方面，Mini-FLOTAC法优于半定量浮选法和麦克马斯特法，具有更高的敏感性，能检测到更高的EPG，尤其是对于圆线虫、类圆线虫属和莫尼茨绦虫属。因此，基于Mini-FLOTAC法EPG做出的治疗决策将导致更多的治疗。
