Molecular and Morphological Characterization of Anisakis simplex in Frozen and Smoked Herring and Mackerel Fish species in Egypt

Abstract

Food-borne zoonoses are of serious public health concern, with a high risk on human health in both developed and developing countries. Thus, this study aimed to determine the prevalence of zoonotic anisakis larvae in smoked imported herring fish (Clupea harengus) and frozen mackerel (Scomber scomberus) from Assiut and Menoufia governorates, respectively in Egypt. All herring specimens were heavily infected with Anisakis larvae, while 9 out of 15 mackerel fish were infected. A total of 434 Anisakis larvae were collected from stomach, abdominal cavity, liver, between skin, muscles and gonads of 45 herring fish. In frozen mackerel, number of detected larvae was 78. Sequencing and phylogenetic analysis of internal transcribed spacer rDNA (ITS-rDNA) ribosomal DNA confirmed that the Anisakis larvae belonged to Anisakis simplex species. Furthermore, by employing light and scanning electron microscope, the morphological characters of Anisakis larvae were also determined. These findings highlight the importance of detecting health hazards in seafood products for helping in the management and prevention of anisakiasis.