Prevalence and molecular identification of zoonotic Anisakis and Pseudoterranova species in fish destined to human consumption in Chile

Abstract

Zoonotic larvae of the family Anisakidae found in several fish species represent a serious risk in public health since they may cause food-borne anisakidosis in humans. Chile has culinary preferences including eating raw fish in many traditional preparations. In the present study, a total of 180 fish specimens representing three different fish species, i.e., Chilean hake (Merluccius gayi), snoek (Thyrsites atun), and sea bream (Brama australis), were caught at central coast of Chile. Parasitological examination was performed on musculature and abdominal cavity for subsequent extraction and quantification of anisakid larvae. Estimation of infection parameters, such as prevalence, was performed indicating 100% (CI: 0.94–1.0) prevalence of anisakid L3 in Chilean hakes and snoeks. Moreover, sea breams reached a prevalence of 35% (CI: 0.23–0.48). Prevalence of anisakid larvae in muscle was also analyzed showing values of 18.6% (CI: 0.097–0.309) in Chilean hakes, 15% (CI: 0.07–0.26) in snoeks, and 1.7% (CI: 0–0.089) in sea breams. Meanwhile, prevalence of anisakid larvae in internal organs showed highest values for peritoneum (100% and 83.3%) for snoeks and Chilean hakes, respectively, for liver (96.7%) and gonads (86.6%) in Chilean hakes, and for intestine (98.3%) in snoeks. Molecular analysis of collected anisakid L3 unveiled presence of two potentially zoonotic nematode species, i.e., Pseudoterranova cattani and Anisakis pegreffii. P. cattani was found in Chilean hakes and snoeks being the first molecular host species report for Chilean snoeks. Besides, A. pegreffii was also identified in these species being the first molecular report on this regard. These findings are relevant for better understanding of epidemiology of anisakiasis in Chilean coasts and for public health issues considering potential risk of human population due to its culinary preferences in eating raw fish.

An investigation of the prevalence and diversity of Anisakis in China: marine food safety implications

“…A recent study examining ready-to-eat mackerel (Scomber japonicus) samples in Japan found that 54% (244/448) were infected with Anisakis nematode (Ohnishi et al, 2023). In Chile, a survey indicated that almost all Chilean hake (Merluccius gayi) and sea bream (Brama australis) were parasitized with Anisakis (Muñoz-Caro et al, 2022). Another survey in Portugal on European hake (M. merluccius) showed that Anisakis had a prevalence of 76.7% (Santos et al, 2022).…”

Gene expression and allergenic potential of Pseudoterranova bulbosa L3 from different infection sites in North Atlantic cod (Gadus morhua)

“…We observed a distribution of Pseudoterranova bulbosa in different microhabitats, liver and viscera, within the body cavity of Atlantic Cod ( Gadus morhua ) caught off Greenland. Since aggregations of anisakid larvae have often been observed in the liver of fish hosts (Klapper et al., 2018; Muñoz‐Caro et al., 2022; Nadolna & Podolska, 2014; Najda et al., 2018; Severin et al., 2020), we hypothesized that this effect could become visible in a differential gene expression analysis, giving insight into the activities (e.g., feeding on blood or tissue in the liver) of anisakid L3 within their paratenic fish host.…”