Surveillance and diagnosis of zoonotic foodborne parasites

Abstract Foodborne parasites are a source of human parasitic infection. Zoonotic infections of humans arise from a variety of domestic and wild animals, including sheep, goats, cattle, camels, horses, pigs, boars, bears, felines, canids, amphibians, reptiles, poultry, and aquatic animals such as fishes and shrimp. Therefore, the implementation of efficient, accessible, and controllable inspection policies for livestock, fisheries, slaughterhouses, and meat processing and packaging companies is highly recommended. In addition, more attention should be paid to the education of auditors from the quality control (QC) and assurance sectors, livestock breeders, the fishery sector, and meat inspection veterinarians in developing countries with high incidence of zoonotic parasitic infections. Furthermore, both the diagnosis of zoonotic parasitic infections by inexpensive, accessible, and reliable identification methods and the organization of effective control systems with sufficient supervision of product quality are other areas to which more attention should be paid. In this review, we present some examples of successful inspection policies and recent updates on present conventional, serologic, and molecular diagnostic methods for zoonotic foodborne parasites from both human infection and animal‐derived foods.


| Monitoring and inspection
Themajorreasonforthemonitoringandinspectionofanimal-derived foods is to guarantee food safety (Berends & Van Knapen, 1999;Naugle,Holt,Levine,&Eckel,2005).Aslongasmanhaseatenmeat, some kind of evaluation of safety and meat quality has most likely been carried out. Early control systems are in religious texts, which gives rules for the edibility of meat (Eliasi & Dwyer, 2002;Farouk, 2013). In this century in Europe, the European Commission has implemented a regulatory program 178/2002 to establish the general principlesandrequirementsoffoodlaws (Frentzel,Menrath,Tomuzia, Braeunig,&Appel,2013),andalloftheEUmemberstateshavehad their own meat inspection systems long before the European commonsystem.Forexample,inFinland,trichinellainspectionstartedin 1867, and in addition to imported meat, domestic animals are controlledcurrentlyforpresenceoftrichinellainfection (Sukura,Nareaho, Mikkonen, Niemi, & Oivanen, 2002). The scientific panels and committees of European Food Safety Authority (EFSA) also advised the procedures for matters of food safety to European member states. 1. Nergal-Abattoir is a compulsory regulatory system that was designed by the French Ministry of Agriculture and implemented in several slaughterhouses (Dupuy etal., 2013). It has been a potent meat surveillance and inspection project in France since 2006. This online system collects demographic data such as age, sex, and breed and health related data of slaughtered cattle.

| Diagnosis of zoonotic foodborne parasites from both human infection and animal-derived foods
The control of animal-derived foods for the presence of zoonotic foodborne parasites is a high-priority for the safety and quality as-  (Pozio,Rossi,&DipartimentoDiMalattie InfettiveParassitarieEImmunomediate,2008).Somelaboratorytechniques that are used to diagnose human infections can also be applied for the detection of parasites in food animals. To design new molecular-based diagnostic methods to detect foodborne parasites, weshouldunderstandthepresentstatusofdiagnosticassaysforeach parasite.Inthisreview,weclassifiedthezoonoticfoodborneparasites from both human infections and animal-derived foods as helminths (Trematoda, Cestoda, and Nematoda) and protozoans. Additionally, we presented the latest progress in conventional, serologic, and molecular diagnostic methods for detection of parasites from both human infection and animal-derived foods (Figure1). A summary of thesediagnosticmethodsisshowninTable1. Approximatelyahundredspeciesoffoodbornetrematodesinfecthumans(Fried&Abruzzi,2010;Keiser,Duthaler,&Utzinger,2010),and someexamplesarediscussedherein.

| Anisakis simplex
The nematode Anisakis simplex is the causative agent of anisakiasis,

| Gnathostoma spp.
Parasitic nematodes Gnathostoma spp. are the causative agents of gnathostomiasis.Humanexposuretothisparasiteishighlydependent on the ingestion of undercooked meat, including shrimp and fish.

Amagnetic-capturepolymerasechainreaction(MC-PCR)wasused
to detect T. gondiiDNAin231horsemeatsamplesfromFrenchsupermarkets for the molecular identification of toxoplasmosis, and theresultswerecomparedwithanELISA(Aroussietal.,2015).The MC-PCRdetectedT. gondiiDNAin43%ofthehorsemeatsamples, while the ELISA was able to detect the infection in 13%-90% of the samples.Therefore, no correlationwas identified between the MC-PCR and ELISA assays for T. gondii DNA. In addition, T. gondii ITS1-derived primers and a fluorogenic probe have been used to detect the protozoan infection in mice and pork meat samples by real-time PCR (Jauregui, Higgins, Zarlenga, Dubey, & Lunney, 2001

| CONCLUSIONS
The "top ten" foodborne parasites of the FAO-WHO in July 2014 (FAO,2014) Additionally, these methods can be applied now to develop selectedparasite-freefarmingsystemsforspecificconsumergroups,althoughastudyoffarmingconditionsrevealedthattheircurrentstatus does not guarantee the production of Toxoplasma-free pork (Djokic etal.,2016).

CONFLICT OF INTEREST
Theauthorsdeclarethattheyhavenoconflictofinterests.