Morphological and molecular identification of third-stage larvae of Anisakis typica (Nematoda: Anisakidae) from Red Sea coral trout, Plectropomus areolatus

Abstract

Anisakidosis is a foodborne zoonotic infection induced by members of the family Anisakidae via the consumption of raw or undercooked fish such as sushi and sashimi. Identifying anisakid larval species is critical for the epidemiology and diagnosis of diseases caused by them. This study aimed at identifying Anisakis larvae collected from marine fish in Egyptian waters based on morphological characteristics and molecular analysis. Thirty marine fish bar-cheeked trout, Plectropomus maculatus, were collected from Hurghada, Red Sea, Egypt, to investigate larval nematodes of the genus Anisakis. The larvae were detected encapsulated in the peritoneal cavity and muscle of the fish host. This examination revealed that anisakid larvae naturally infected 19 fish specimens with a prevalence of 63.33% and a mean intensity of 4.1 ± 0.40. Most of them (68 larvae: 71.57%) were found in the musculature. Morphological and morphometric analyses using light and scanning electron microscopy revealed a head region with a prominent boring tooth, inconspicuous lips, and a characteristic protruded cylindrical mucron. All larvae in this study possessed the same morphology as Anisakis Larval type I. Molecular analysis based on ITS region using maximum likelihood and Bayesian phylogenetic methods confirmed them as Anisakis typica. This is the first study to identify A. typica larvae from the commercial fish bar-cheeked trout P. maculatus in Egyptian waters using morphological and molecular methods.

Anisakiasis in the Upper Esophagus: A Case Report

“…Previous reports described the Anisakis sp. larvae as displaying a cylindrical body shape, tapered at both ends, and with dimensions of 14.1-25.6 mm in length (a mean of 20.4 ± 1.2 mm) and 0.48-0.62 mm in width (a mean of 0.55 ± 0.02 mm) [6,7]. Microscopically, such larvae are enveloped by a rigid cuticle featuring circular transverse striations that commence from the cephalic region and extend toward the anus and which have a slit-shaped appearance.…”

One Health approach for prioritization of potential foodborne pathogens: Risk‐ranking, Delphi survey, and criteria evaluation pre‐ and post‐COVID‐19 pandemic

“…This matches the results of prioritization by VET experts, selecting Anisakis at the highest rate both before and after the pandemic (Table 3). Anisakiasis has been prevalent in Asia and Europe, including Japan, where cuisines made with raw or undercooked seafood (i.e., sushi and sashimi) are highly consumed (Mostafa et al., 2023).…”

Recombinase polymerase amplification combined with lateral flow dipstick assay for rapid visual detection of A.simplex (s. s.) and A.pegreffii in sea foods

“…Several techniques have been developed and used to identify Anisakis in food safety supervision and clinical examination. Traditional identification methods involve morphology identification, such as visual inspection, enzyme digestion, and ultraviolet-press methods [ [20] , [21] , [22] ]. Morphological identification is simple, rapid, and practicable; yet, damage or fragmentation during the egg stage or early stages of infection in fish and humans [ 23 , 24 ] and variations in structure and morphology during larval different developmental stages of Anisakis, as well as the impact of external environmental factors are some of the main challenges using this method for Anisakis detection in processed products such as surimi and canned fish [ 25 ].…”