Laboratory of Foodborne Parasitic Zoonoses, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, Belgium.
Laboratory of Foodborne Parasitic Zoonoses, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, Belgium.
Int J Food Microbiol. 2020 Aug 16;327:108657. doi: 10.1016/j.ijfoodmicro.2020.108657. Epub 2020 May 8.
Anisakidae and Raphidascaridae are marine nematodes present in a wide range of fish hosts, which may cause gastro-intestinal complaints and/or allergy in human, in addition to economic losses for the industry. Data regarding the presence of these parasites in fish for the Belgian market is currently missing; therefore, our aim was to investigate the presence and intensity of ascaridoids in a wide range of commercially fish species. A total of 415 fish samples, belonging to 36 different fish species, were collected from a Belgian whole-sale company. Ascaridoid larvae from the viscera (if present) and the muscles were collected by enzymatic digestion and the prevalence, median intensity, mean number of larvae per 100 g infected muscle, and localisation were determined. An overall prevalence of 53% [95%-CI: 42-63%] in the viscera and 27% [95%-CI: 23-32%] in the muscles was observed. Infection in the muscles varied between the fish species; no larvae were detected in 13 fish species, while a high prevalence (>78%) was observed in pollack, halibut, and gurnard. Most samples originated from the Northeast Atlantic Ocean, with the highest prevalence in the muscles observed in the Barents & Norwegian Sea (65% [95%-CI: 38-86]). Muscle samples were, if possible, divided in an anterior region, belly flap, medial region, and posterior region, with the most infections and larvae found in the belly flaps. In all samples, a total of 2569 larvae were recovered, with 1594 larvae originating from the viscera and 975 from the muscles; with an average of two larvae per 100 g infected fillet detected. Larvae were morphologically identified, and a subgroup was further confirmed using PCR/RFLP, resulting ultimately in the identification of Anisakis simplex s.s. (1853 larvae), A. pegreffii (137), A. simplex/pegreffii hybrid genotype (38), Pseudoterranova decipiens (160) and Hysterothylacium aduncum (380). This study demonstrates that ascaridoid larvae are highly prevalent in different fish species on the Belgian market.
海蛔科和圆线科是广泛存在于鱼类宿主中的海洋线虫，它们可能会引起人类的胃肠道不适和/或过敏，此外还会给渔业造成经济损失。目前，有关这些寄生虫在比利时市场鱼类中的存在的数据尚不清楚；因此，我们的目的是调查广泛的商业鱼类物种中蛔目线虫的存在和强度。从一家比利时批发商处采集了 415 个属于 36 个不同鱼类物种的鱼样本。通过酶消化收集内脏（如有）和肌肉中的蛔目幼虫，并确定其流行率、中位数强度、每 100 克感染肌肉中的幼虫平均数和定位。在内脏中观察到 53%[95%CI：42-63%]的总体流行率，在肌肉中观察到 27%[95%CI：23-32%]。肌肉中的感染在鱼类之间有所不同；13 种鱼类中未检测到幼虫，而在牙鳕、大比目鱼和鲂鮄中观察到高流行率（>78%）。大多数样本来自东北大西洋，在巴伦支海和挪威海观察到的肌肉中流行率最高（65%[95%CI：38-86%]）。如果可能，肌肉样本分为前区、腹鳍、中区和后区，腹鳍中发现的感染和幼虫最多。在所有样本中，共回收了 2569 条幼虫，其中 1594 条幼虫来自内脏，975 条幼虫来自肌肉；每 100 克感染鱼片检测到平均 2 条幼虫。幼虫进行了形态学鉴定，一小部分通过 PCR/RFLP 进一步确认，最终鉴定出单纯异尖线虫（1853 条幼虫）、拟异尖线虫（137 条）、单纯/拟异尖线虫杂种基因型（38 条）、伪旋尾线虫（160 条）和东方次睾吸虫（380 条）。本研究表明，在比利时市场上的不同鱼类中，蛔目幼虫的流行率很高。
