Towards a standardised surveillance for Trichinella in the European Union

First Identification of Trichinella pseudospiralis in a Golden Jackal (Canis aureus) in Romania

Trichinella spp. are etiological zoonotic agents that spread throughout the world and affect mammals, birds, and reptiles. Within this genus, Trichinella pseudospiralis is the only recognized non-encapsulated species known to infect mammals and birds. This species has been reported in the majority of European countries, and the real epidemiological scenario of this species remains to be defined because its detection in mammals is much lower than that of the capsulated species. The aim of this study was to examine the presence of Trichinella larvae isolated from the muscles of a jackal from the hunting fund of 36 Murfatlar, Constanta County, Romania. The muscle samples were examined by artificial digestion, and the larvae were identified at the species level by multiplex PCR. The presence of larvae belonging to T. pseudospiralis, a species more frequently reported in carnivorous birds, was observed. This study describes the first identification of T. pseudospiralis in a jackal. The results suggest that there is an urgent need to investigate which species of mammals and/or birds act as reservoirs for this zoonotic nematode in Romania.

The European Union One Health 2022 Zoonoses Report

This report by the European Food Safety Authority and the European Centre for Disease Prevention and Control presents the results of the zoonoses monitoring and surveillance activities carried out in 2022 in 27 Member States (MSs), the United Kingdom (Northern Ireland) and 11 non-MSs. Key statistics on zoonoses and zoonotic agents in humans, food, animals and feed are provided and interpreted historically. In 2022, the first and second most reported zoonoses in humans were campylobacteriosis and salmonellosis, respectively. The number of cases of campylobacteriosis and salmonellosis remained stable in comparison with 2021. Nineteen MSs and the United Kingdom (Northern Ireland) achieved all the established targets in poultry populations for the reduction of Salmonella prevalence for the relevant serovars. Salmonella samples from carcases of various animal species, and samples for Campylobacter quantification from broiler carcases, were more frequently positive when performed by the competent authorities than when own checks were conducted. Yersiniosis was the third most reported zoonosis in humans, followed by Shiga toxin-producing Escherichia coli (STEC) and Listeria monocytogenes infections. L. monocytogenes and West Nile virus infections were the most severe zoonotic diseases, with the most hospitalisations and highest case fatality rates. In 2022, reporting showed an increase of more than 600% compared with 2021 in locally acquired cases of human West Nile virus infection, which is a mosquito-borne disease. In the EU, the number of reported foodborne outbreaks and cases, hospitalisations and deaths was higher in 2022 than in 2021. The number of deaths from outbreaks was the highest ever reported in the EU in the last 10 years, mainly caused by L. monocytogenes and to a lesser degree by Salmonella. Salmonella and in particular S. Enteritidis remained the most frequently reported causative agent for foodborne outbreaks. Norovirus (and other calicivirus) was the agent associated with the highest number of outbreak human cases. This report also provides updates on brucellosis, Coxiella burnetii (Q fever), echinococcosis, rabies, toxoplasmosis, trichinellosis, infection with Mycobacterium tuberculosis complex (focusing on Mycobacterium bovis and Mycobacterium caprae) and tularaemia.

A Quality Assurance Discrimination Tool for the Evaluation of Satellite Laboratory Practice Excellence in the Context of the European Official Meat Inspection for Trichinella spp

Trichinellosis is a parasitic foodborne zoonotic disease transmitted by ingestion of raw or undercooked meat containing the first larval stage (L1) of the nematode. To ensure the quality and safety of food intended for human consumption, meat inspection for detection of Trichinella spp. larvae is a mandatory procedure according to EU regulations. The implementation of quality assurance practices in laboratories that are responsible for Trichinella spp. detection is essential given that the detection of this parasite is still a pivotal threat to public health, and it is included in list A of Annex I, Directive 2003/99/EC, which determines the agents to be monitored on a mandatory basis. A Quality Management System (QMS) was applied to slaughterhouses and game handling establishments conducting Trichinella spp. testing without official accreditation but under the supervision of the relevant authority. This study aims to retrospectively analyze the outcomes of implementing the QMS in slaughterhouses and game handling establishments involved in Trichinella testing in southern Spain. Canonical discriminant analyses (CDAs) were performed to design a tool enabling the classification of SLs while determining whether linear combinations of measures of quality-assurance-related traits describe within- and between-SL clustering patterns. The participation of two or more auditors improves the homogeneity of the results deriving from audits. However, when training expertise ensures that such levels of inter-/intralaboratory homogeneity are reached, auditors can perform single audits and act as potential trainers for other auditors. Additionally, technical procedure issues were the primary risk factors identified during audits, which suggests that they should be considered a critical control point within the QMS.

Role of Bacteriophages for Optimized Health and Production of Poultry

The poultry sector is facing infections from Salmonella, Campylobacter, Listeria and Staphylococcus spp., and Escherichia coli, that have developed multidrug resistance aptitude. Antibiotics cause disturbances in the balance of normal microbiota leading to dysbiosis, immunosuppression, and the development of secondary infections. Bacteriophages have been reported to lower the colonization of Salmonella and Campylobacter in poultry. The specificity of bacteriophages is greater than that of antibiotics and can be used as a cocktail for enhanced antibacterial activity. Specie-specific phages have been prepared, e.g., Staphylophage (used against Staphylococcus bacteria) that specifically eliminate bacterial pathogens. Bacteriophage products, e.g., BacWash^TM and Ecolicide PX have been developed as antiseptics and disinfectants for effective biosecurity and biosafety measures. The success of phage therapy is influenced by time to use, the amount used, the delivery mechanism, and combination therapy with other therapeutics. It is a need of time to build a comprehensive understanding of the use of bacteriophages in poultry production. The current review thus focuses on mechanisms of bacteriophages against poultry pathogens, their applications in various therapeutics, impacts on the economy, and current challenges.

The European Union One Health 2021 Zoonoses Report

This report of the European Food Safety Authority and the European Centre for Disease Prevention and Control presents the results of zoonoses monitoring and surveillance activities carried out in 2021 in 27 MSs, the United Kingdom (Northern Ireland) and nine non-MSs. Key statistics on zoonoses and zoonotic agents in humans, food, animals and feed are provided and interpreted historically. In 2021, the first and second most reported zoonoses in humans were campylobacteriosis and salmonellosis, respectively. Cases of campylobacteriosis and salmonellosis increased in comparison with 2020, but decreased compared with previous years. In 2021, data collection and analysis at the EU level were still impacted by the COVID-19 pandemic and the control measures adopted in the MSs, including partial or total lockdowns. Sixteen MSs and the United Kingdom (Northern Ireland) achieved all the established targets in poultry populations for reduction in Salmonella prevalence for the relevant serovars. Salmonella samples from carcases of various animal species and samples for Campylobacter quantification from broiler carcases were more frequently positive when performed by the competent authorities than when own-checks were conducted. Yersiniosis was the third most reported zoonosis in humans, followed by Shiga toxin-producing Escherichia coli (STEC) and Listeria monocytogenes infections. L. monocytogenes and West Nile virus infections were the most severe zoonotic diseases, with the most hospitalisations and highest case fatality rates. Overall, MSs reported more foodborne outbreaks and cases in 2021 than in 2020. S. Enteritidis remained the most frequently reported causative agent for foodborne outbreaks. Salmonella in 'eggs and egg products' and in 'mixed foods' were the agent/food pairs of most concern. Outbreaks linked to 'vegetables and juices and products thereof' rose considerably compared with previous years. This report also provides updates on brucellosis, Coxiella burnetii (Q fever), echinococcosis, rabies, toxoplasmosis, trichinellosis, tuberculosis due to Mycobacterium bovis or M. caprae, and tularaemia.

The European Union One Health 2020 Zoonoses Report

This report of the EFSA and the European Centre for Disease Prevention and Control presents the results of zoonoses monitoring activities carried out in 2020 in 27 EU Member States (MS) and nine non-MS. Key statistics on zoonoses and zoonotic agents in humans, food, animals and feed are provided and interpreted historically. Two events impacted 2020 MS data collection and related statistics: the Coronavirus Disease 2019 (COVID-19) pandemic and the withdrawal of the United Kingdom from the EU. In 2020, the first and second most reported zoonoses in humans were campylobacteriosis and salmonellosis, respectively. The EU trend for confirmed human cases of these two diseases was stable (flat) from 2016 to 2020. Fourteen of the 26 MS reporting data on Salmonella control programmes in poultry met the reduction targets for all poultry categories. Salmonella results for carcases of various species performed by competent authorities were more frequently positive than own-checks conducted by food business operators. This was also the case for Campylobacter quantification results from broiler carcases for the MS group that submitted data from both samplers, whereas overall at EU level, those percentages were comparable. Yersiniosis was the third most reported zoonosis in humans, with 10-fold less cases reported than salmonellosis, followed by Shiga toxin-producing Escherichia coli (STEC) and Listeria monocytogenes infections. Illnesses caused by L. monocytogenes and West Nile virus infections were the most severe zoonotic diseases with the highest case fatality. In 2020, 27 MS reported 3,086 foodborne outbreaks (a 47.0% decrease from 2019) and 20,017 human cases (a 61.3% decrease). Salmonella remained the most frequently reported causative agent for foodborne outbreaks. Salmonella in 'eggs and egg products', norovirus in 'crustaceans, shellfish, molluscs and products containing them' and L. monocytogenes in 'fish and fish products' were the agent/food pairs of most concern. This report also provides updates on tuberculosis due to Mycobacterium bovis or Mycobacterium caprae, Brucella, Trichinella, Echinococcus, Toxoplasma, rabies, Coxiella burnetii (Q fever) and tularaemia.

The European Union One Health 2019 Zoonoses Report

This report of the EFSA and the European Centre for Disease Prevention and Control presents the results of zoonoses monitoring activities carried out in 2019 in 36 European countries (28 Member States (MS) and eight non-MS). The first and second most reported zoonoses in humans were campylobacteriosis and salmonellosis, respectively. The EU trend for confirmed human cases of these two diseases was stable (flat) during 2015-2019. The proportion of human salmonellosis cases due to Salmonella Enteritidis acquired in the EU was similar to that in 2017-2018. Of the 26 MS reporting on Salmonella control programmes in poultry, 18 met the reduction targets, whereas eight failed to meet at least one. The EU prevalence of Salmonella target serovar-positive flocks has been stable since 2015 for breeding hens, laying hens, broilers and fattening turkeys, with fluctuations for breeding turkey flocks. Salmonella results from competent authorities for pig carcases and for poultry tested through national control programmes were more frequently positive than those from food business operators. Shiga toxin-producing Escherichia coli (STEC) infection was the third most reported zoonosis in humans and increased from 2015 to 2019. Yersiniosis was the fourth most reported zoonosis in humans in 2019 with a stable trend in 2015-2019. The EU trend of confirmed listeriosis cases remained stable in 2015-2019 after a long period of increase. Listeria rarely exceeded the EU food safety limit tested in ready-to-eat food. In total, 5,175 food-borne outbreaks were reported. Salmonella remained the most detected agent but the number of outbreaks due to S. Enteritidis decreased. Norovirus in fish and fishery products was the agent/food pair causing the highest number of strong-evidence outbreaks. The report provides further updates on bovine tuberculosis, Brucella, Trichinella, Echinococcus, Toxoplasma, rabies, West Nile virus, Coxiella burnetii (Q fever) and tularaemia.

Trichinella britovi as a risk factor for alternative pig production systems in Greece and Europe

Trichinellosis is an important zoonosis and the most common source of human infection is meat from pigs and wild boars. The European Union (EU) supports alternative pig production systems (organic and free-ranging) as sustainable farming systems. However, these systems that allow outdoor access for farm animals, may create new or reintroduce old risks to public health. During the last years, alternative pig production systems (free-ranging or organic pig) are growing in popularity in Greece due to the increasing interest of consumers for organic products. The majority of the trichinellosis outbreaks in the EU were associated with pork and meat products including wild boars. In Greece, from 2009 to 2012, 37 Trichinella spp. positive free-ranging pigs were reported in free-ranging pig farms of Northern-Eastern Greece (31 were identified as T. britovi). The recent re-emerging present of the Trichinella spp. infections in free-ranging pigs and wild boars are a high risk for the consumers and should alarm the Public Health Authorities in Greece and the EU. During the last years, the organic or free-ranging pig production systems are growing in popularity in the EU. However, these systems increase the risk of Trichinella spp. infections, since pigs are possible to be infected by feeding on carcasses or the offal of hunted or dead wild animals. For this reason, it is important for Public Health Authorities to be focused on the training of hunters and farmers in order to avoid the transmission among free-ranging pigs and prevent the cases of human infection.

Trichinella spiralis – New method for sample preparation and objective detection of specific antigens using a chemiluminescence immunoassay

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Introduction of a new sample preparation method involving shredding of pork.

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Automated detection of specific T. spiralis antigens via chemiluminescence.

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Trichinella ChLIA detects antigens of 1 larva in 100 g infected pork (0.01 lpg).

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Objective evaluation via Trichinella ChLIA allows reliable meat inspection.

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Meat inspection is faster with the new method than with the gold standard.

The parasitic roundworm Trichinella spiralis is most commonly transmitted to humans through consumption of raw or undercooked meat of infected pigs or game. To prevent human infection, slaughterhouses perform meat safety surveillance using the gold standard “Magnetic Stirrer Method”. We introduce a fast and objective method using automated detection of specific Trichinella spiralis antigens by a newly developed immunoassay based on chemiluminescence (ChLIA). Panel A comprised muscle tissue samples from non-infected pigs (n = 37). Panel B comprised muscle tissue samples from non-infected pigs spiked with different amounts of Trichinella larvae without collagen capsules (n = 56). Panel C contained muscle tissue samples from experimentally infected pigs including Trichinella larvae encapsulated in collagen (n = 32). Each sample was shredded with PBS buffer in a knife mill, destroying Trichinella larvae. Following centrifugation, the supernatant (muscle tissue extract containing released excretory and secretory Trichinella spiralis antigens) was used for Trichinella-specific antigen detection by the new Trichinella ChLIA. The overall accuracy of the Trichinella ChLIA was 97.6 %. The specificity of the Trichinella ChLIA was 100 % (panel A). The sensitivity in samples from experimentally infected pigs was 100 % representing a detection limit of 0.01 larvae per gram. Cross-reactivity with parasites other than Trichinella spp. was not observed. This new meat inspection method for the detection of Trichinella spiralis antigens presents high specificity and high sensitivity, especially in truly infected samples. In contrast to the gold standard, this new approach to meat safety surveillance does not require longsome digestion or microscopy by trained personnel.

The European Union One Health 2018 Zoonoses Report

This report of the European Food Safety Authority and the European Centre for Disease Prevention and Control presents the results of zoonoses monitoring activities carried out in 2018 in 36 European countries (28 Member States (MS) and 8 non‐MS). The first and second most commonly reported zoonoses in humans were campylobacteriosis and salmonellosis, respectively. The European Union (EU) trend for confirmed human cases of these two diseases was stable during 2014–2018. The proportion of human salmonellosis cases due to Salmonella Enteritidis was at the same level in 2018 as in 2017. Of the 27 reporting MS, 16 met all Salmonella reduction targets for poultry, whereas 11 MS failed meeting at least one. The EU flock prevalence of target Salmonella serovars in breeding hens, laying hens, broilers and fattening turkeys decreased during recent years but stalled in breeding turkeys. Salmonella results from Competent Authorities for pig carcasses and for poultry tested through National Control Programmes were more frequently positive compared with food business operators. Shiga toxin‐producing Escherichia coli (STEC) infections in humans were the third most commonly reported zoonosis in the EU and increased from 2014 to 2018. Yersiniosis was the fourth most frequently reported zoonosis in humans in 2018 with a stable trend in 2014–2018. The number of reported confirmed listeriosis cases further increased in 2018, despite Listeria rarely exceeding the EU food safety limit tested in ready‐to‐eat food. In total, 5,146 food‐ and waterborne outbreaks were reported. Salmonella was the most commonly detected agent with S. Enteritidis causing one in five outbreaks. Salmonella in eggs and egg products was the highest risk agent/food pair. A large increase of human West Nile virus infections was reported in 2018. The report further updates on bovine tuberculosis, Brucella, Trichinella, Echinococcus, Toxoplasma, rabies, Coxiella burnetii (Q fever) and tularaemia.

Risk-based surveillance for meat-borne parasites

There is a plethora of meat-borne hazards - including parasites - for which there may be a need for surveillance. However, veterinary services worldwide need to decide how to use their scarce resources and prioritise among the perceived hazards. Moreover, to remain competitive, food business operators - irrespective of whether they are farmers or abattoir operators - are preoccupied with maintaining a profit and minimizing costs. Still, customers and trade partners expect that meat products placed on the market are safe to consume and should not bear any risks of causing disease. Risk-based surveillance systems may offer a solution to this challenge by applying risk analysis principles; first to set priorities, and secondly to allocate resources effectively and efficiently. The latter is done through a focus on the cost-effectiveness ratio in sampling and prioritisation. Risk-based surveillance was originally introduced into veterinary public health in 2006. Since then, experience has been gathered, and the methodology has been further developed. Guidelines and tools have been developed, which can be used to set up appropriate surveillance programmes. In this paper, the basic principles are described, and by use of a surveillance design tool called SURVTOOLS (https://survtools.org/), examples are given covering three meat-borne parasites for which risk-based surveillance is 1) either in place in the European Union (EU) (Trichinella spp.), 2) to be officially implemented in December 2019 (Taenia saginata) or 3) only carried out by one abattoir company in the EU as there is no official EU requirement (Toxoplasma gondii). Moreover, advantages, requirements and limitations of risk-based surveillance for meat-borne parasites are discussed.

International Commission on Trichinellosis: Recommendations for quality assurance in digestion testing programs for Trichinella

Effective performance of digestion testing methods for Trichinella, and their use for the detection of infected animals and the prevention of human trichinellosis require system-wide incorporation of appropriate quality assurance (QA) practices. The recommendations of the International Commission on Trichinellosis (ICT) aim to facilitate reliable test results when laboratories operate within a quality management system (QMS) which includes: 1) a quality manual (or similar documentation of the QMS); 2) a validated test method with identified critical control points; 3) a training program; 4) procedures utilizing proficiency testing and other methods to confirm technical capability of analysts; 5) equipment calibration and maintenance; 6) standard operating procedures, related documentation and reporting; 7) procedures to enable continuous monitoring and improvements; and 8) regular internal and third party audits. The quality manual or similar documentation describes the QMS within a testing laboratory, and lists the QA policies and good laboratory practices. Quality assurance goals contained in such documentation are the foundation of an effective QA program and must be explicit, measurable, and expressed in terms of performance criteria for the test method based on purpose for testing. The digestion method is capable of consistently detecting Trichinella larvae in meat at a level of sensitivity that is recognized to be effective for use in controlling animal infection and preventing human disease. However, consistent performance of the assay is assured only when parameters of the test method have been defined, scientifically validated as fit for purpose, and used within an effective QMS. The essential components of a digestion assay, specifically the critical control points and minimum standards for test performance are described. Reliable proficiency samples and their appropriate use in a quality system are key factors for certifying and maintaining an effective testing laboratory, including qualifying, re-qualifying and disqualifying of analysts as appropriate. Thus recommendations are included for the preparation and use of proficiency samples in a Trichinella digestion testing laboratory. The minimum training requirements for analysts performing a quality assured digestion assay, as well as suggested requirements for the content of a training manual, are also outlined. Finally, these ICT recommendations include essential components and minimum standards for maintaining and achieving certification and maintenance of a laboratory performing digestion testing for Trichinella. The certification program for the laboratory, including qualifying analysts, may be administered by a National Reference Laboratory or an authorized third party certifying body, under the auspices of the appropriate competent authority.

The European Union summary report on trends and sources of zoonoses, zoonotic agents and food-borne outbreaks in 2017

This report of the European Food Safety Authority and the European Centre for Disease Prevention and Control presents the results of zoonoses monitoring activities carried out in 2017 in 37 European countries (28 Member States (MS) and nine non-MS). Campylobacteriosis was the commonest reported zoonosis and its EU trend for confirmed human cases increasing since 2008 stabilised during 2013-2017. The decreasing EU trend for confirmed human salmonellosis cases since 2008 ended during 2013-2017, and the proportion of human Salmonella Enteritidis cases increased, mostly due to one MS starting to report serotype data. Sixteen MS met all Salmonella reduction targets for poultry, whereas 12 MS failed meeting at least one. The EU flock prevalence of target Salmonella serovars in breeding hens, laying hens, broilers and fattening turkeys decreased or remained stable compared to 2016, and slightly increased in breeding turkeys. Salmonella results on pig carcases and target Salmonella serovar results for poultry from competent authorities tended to be generally higher compared to those from food business operators. The notification rate of human listeriosis further increased in 2017, despite Listeria seldom exceeding the EU food safety limit in ready-to-eat food. The decreasing EU trend for confirmed yersiniosis cases since 2008 stabilised during 2013-2017. The number of confirmed shiga toxin-producing Escherichia coli (STEC) infections in humans was stable. A total of 5,079 food-borne (including waterborne) outbreaks were reported. Salmonella was the commonest detected agent with S. Enteritidis causing one out of seven outbreaks, followed by other bacteria, bacterial toxins and viruses. The agent was unknown in 37.6% of all outbreaks. Salmonella in eggs and Salmonella in meat and meat products were the highest risk agent/food pairs. The report further summarises trends and sources for bovine tuberculosis, Brucella, Trichinella, Echinococcus, Toxoplasma, rabies, Coxiella burnetii (Q fever), West Nile virus and tularaemia.

Occurrence of selected zoonotic food-borne parasites and first molecular identification of Alaria alata in wild boars (Sus scrofa) in Italy

Wild boar is a source of human infections with zoonotic pathogens, including food-borne parasites. With the aim of a characterization of the human exposure risk, a survey on wild boars intended for human consumption was planned, selecting three pathogens, Toxoplasma gondii, Alaria alata, and Trichinella spp., as markers of meat infection. Diaphragm muscle samples from 100 wild boars hunted in Piedmont region (Northern Italy) in two hunting seasons (2015-2016) were collected. Concerning T. gondii, a combined approach of antibody detection and molecular techniques with genotyping was performed. For the detection of A. alata and Trichinella spp., the larva migration technique and the magnetic stirrer method were employed, respectively; in addition, molecular confirmation of the morphological identification of the recovered specimen was performed. Anti-T. gondii antibodies were found in meat juice samples (43.3%) and T. gondii DNA (type II) was detected in three animals (7.1%) out of 42 seropositive examined. In none of the sampled wild boars (0%), Trichinella spp. larvae were found, whereas one animal (1%) scored positive to A. alata mesocercariae. The molecular diagnosis proved the morphological identification of the trematode. This is the first finding of A. alata in Italian wild boar population. The present study confirmed the role of wild boars as a source of parasitic zoonotic diseases and thus the risk derived for humans posed by the consumption of game meat. Considering the zoonotic implications, the results underline the importance of monitoring and surveillance of zoonotic parasites in Italian wild boar populations.

Assessing the risk of human trichinellosis from pigs kept under controlled and non-controlled housing in Europe

To support risk-based approach to prevent human trichinellosis, we estimated the human incidence for pigs originating from controlled and non-controlled housing, using a quantitative microbial risk assessment model for Trichinella (QMRA-T). Moreover, the effect of test sensitivity on human trichinellosis incidence from pigs from non-controlled housing was quantified. The estimated annual risk from pigs from non-controlled housing was 59,443 human trichinellosis cases without testing at meat inspection and 832 (95%CI 346-1410) cases with Trichinella testing, thus preventing 98.6% of trichinellosis cases per year by testing at meat inspection. Using the QMRA-T, a slight decrease in test sensitivity had a significant effect on the number of human trichinellosis cases from this housing type. The estimated annual risk for pigs from controlled housing was <0.002 (range 0.000-0.007) human cases with- and <0.010 (0.001-0.023) cases without Trichinella testing at meat inspection, which does not differ significantly (p = 0.2075). In practice, this means no cases per year irrespective of Trichinella testing. Thus controlled housing effectively prevents infection and Trichinella testing does not contribute to food safety for this housing type. Not testing for Trichinella requires evidence based full compliance with regulations for controlled housing.

The European Union summary report on trends and sources of zoonoses, zoonotic agents and food-borne outbreaks in 2016

This report of the European Food Safety Authority and the European Centre for Disease Prevention and Control presents the results of the zoonoses monitoring activities carried out in 2016 in 37 European countries (28 Member States (MS) and nine non-MS). Campylobacteriosis was the most commonly reported zoonosis and the increasing European Union (EU) trend for confirmed human cases since 2008 stabilised during 2012-2016. In food, the occurrence of Campylobacter remained high in broiler meat. The decreasing EU trend for confirmed human salmonellosis cases since 2008 ended during 2012-2016, and the proportion of human Salmonella Enteritidis cases increased. Most MS met their Salmonella reduction targets for poultry, except five MS for laying hens. At primary production level, the EU-level flock prevalence of target Salmonella serovars in breeding hens, broilers, breeding and fattening turkeys decreased or stabilised compared with previous years but the EU prevalence of S. Enteritidis in laying hens significantly increased. In foodstuffs, the EU-level Salmonella non-compliance for minced meat and meat preparations from poultry was low. The number of human listeriosis confirmed cases further increased in 2016, despite the fact that Listeria seldom exceeds the EU food safety limit in ready-to-eat foods. The decreasing EU trend for confirmed yersiniosis cases since 2008 stabilised during 2012-2016, and also the number of confirmed Shiga toxin-producing Escherichia coli (STEC) infections in humans was stable. In total, 4,786 food-borne outbreaks, including waterborne outbreaks, were reported. Salmonella was the most commonly detected causative agent - with one out of six outbreaks due to S. Enteritidis - followed by other bacteria, bacterial toxins and viruses. Salmonella in eggs continued to represent the highest risk agent/food combination. The report further summarises trends and sources for bovine tuberculosis, brucellosis, trichinellosis, echinococcosis, toxoplasmosis, rabies, Q fever, West Nile fever and tularaemia.

Surveillance and diagnosis of zoonotic foodborne parasites

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.

Active animal health surveillance in European Union Member States: gaps and opportunities

Animal health surveillance enables the detection and control of animal diseases including zoonoses. Under the EU-FP7 project RISKSUR, a survey was conducted in 11 EU Member States and Switzerland to describe active surveillance components in 2011 managed by the public or private sector and identify gaps and opportunities. Information was collected about hazard, target population, geographical focus, legal obligation, management, surveillance design, risk-based sampling, and multi-hazard surveillance. Two countries were excluded due to incompleteness of data. Most of the 664 components targeted cattle (26·7%), pigs (17·5%) or poultry (16·0%). The most common surveillance objectives were demonstrating freedom from disease (43·8%) and case detection (26·8%). Over half of components applied risk-based sampling (57·1%), but mainly focused on a single population stratum (targeted risk-based) rather than differentiating between risk levels of different strata (stratified risk-based). About a third of components were multi-hazard (37·3%). Both risk-based sampling and multi-hazard surveillance were used more frequently in privately funded components. The study identified several gaps (e.g. lack of systematic documentation, inconsistent application of terminology) and opportunities (e.g. stratified risk-based sampling). The greater flexibility provided by the new EU Animal Health Law means that systematic evaluation of surveillance alternatives will be required to optimize cost-effectiveness.

Regulatory Issues Associated with Preharvest Food Safety: European Union Perspective

Free movement of safe and wholesome food is an essential aspect of any society. This article contains an updated description of the regulatory issues associated with preharvest food safety within the European Union. Salmonella , Campylobacter , Trichinella , antimicrobial resistance, and bovine spongiform encephalopathy are dealt with in detail. Moreover, Cysticercus bovis / Taenia saginata , Toxoplasma , Yersinia , verotoxigenic/shigatoxigenic Escherichia coli , Listeria , and foodborne viruses are briefly covered. The article describes how the focus in the European Union is changing to involve a supply chain view with a focus on cost-effectiveness. The precautionary principle—as well as the use of private standards as an instrument to ensure compliance—is dealt with. In addition, actions in the pipeline are presented and discussed.

Innovative molecular diagnosis of Trichinella species based on β-carbonic anhydrase genomic sequence

Trichinellosis is a helminthic infection where different species of Trichinella nematodes are the causative agents. Several molecular assays have been designed to aid diagnostics of trichinellosis. These assays are mostly complex and expensive. The genomes of Trichinella species contain certain parasite‐specific genes, which can be detected by polymerase chain reaction (PCR) methods. We selected β‐carbonic anhydrase (β‐CA) gene as a target, because it is present in many parasites genomes but absent in vertebrates. We developed a novel β‐CA gene‐based method for detection of Trichinella larvae in biological samples. We first identified a β‐CA protein sequence from Trichinella spiralis by bioinformatic tools using β‐CAs from Caenorhabditis elegans and Drosophila melanogaster. Thereafter, 16 sets of designed primers were tested to detect β‐CA genomic sequences from three species of Trichinella, including T. spiralis, Trichinella  pseudospiralis and Trichinella  nativa. Among all 16 sets of designed primers, the primer set No. 2 efficiently amplified β‐CA genomic sequences from T. spiralis, T. pseudospiralis and T. nativa without any false‐positive amplicons from other parasite samples including Toxoplasma gondii, Toxocara cati and Parascaris equorum. This robust and straightforward method could be useful for meat inspection in slaughterhouses, quality control by food authorities and medical laboratories.

New finding of Trichinella britovi in a European beaver (Castor fiber) in Latvia

We report the first finding of Trichinella britovi in a European beaver. In Latvia, beaver is a common game animal and frequently used in human diet. A high prevalence of Trichinella infections in Latvia is present in the most common hosts-carnivores and omnivores. In total, 182 European beaver muscle samples were tested for Trichinella larvae accordingly to the reference method of European Communities Commission Regulation (EC) No. 2075/2005 (2005). Trichinella britovi larvae were detected in one animal (prevalence 0.5%; intensity 5.92 larvae per gram of muscle). This finding suggests that the consumption of European beaver meat can be a risk to human health. Further studies are needed in order to determine if the present observation represents an isolated individual case or low prevalence of Trichinella infection in beavers.

Outbreak of trichinellosis due to wild boar meat and evaluation of the effectiveness of post exposure prophylaxis, Germany, 2013

BACKGROUND

Food safety authorities discovered that wild boar meat products contaminated with Trichinella spiralis had entered the food chain in Germany in March 2013. Public health authorities issued guidelines for health professionals including post-exposure prophylaxis (PEP) using mebendazole and advised the public to seek medical advice if exposed. Our objective was to identify factors associated with the development of trichinellosis and to evaluate post exposure prophylaxis.

METHODS

Persons who reported to local public health departments as exposed were interviewed concerning exposure, symptoms, and medication. Serum samples were tested by an in-house Trichinella-specific enzyme-linked innunosorbent assay. Cases were defined as persons presenting with myalgia and/or periorbital edema and Trichinella-specific immunoglobulin M and immunoglobulin G antibodies after exposure to implicated products.

RESULTS

Of 101 persons interviewed, 71 were exposed and serologically tested. Antibodies were detected in 21/71 (30%) and 14/71 (20%) met the case definition. Attack rates were positively correlated to the amount of implicated product consumed. Among n = 37 persons who received anthelmintics as PEP, 6 persons developed trichinellosis. These cases exclusively occurred among persons starting PEP 6 days or later post-exposure. Exposure to implicated products and delaying PEP were also significantly associated with developing trichinellosis (P < .01) in a multivariable analysis.

CONCLUSIONS

Concerted efforts by food safety and public health authorities lead to timely outbreak control and facilitated the provision of early PEP. PEP appears to be effective in preventing trichinellosis when given early, preferably within 6 days. We therefore recommend initiating PEP without delay in similar settings and encourage public health professionals to fast-track this intervention.

The low global burden of trichinellosis: evidence and implications

Trichinellosis is a cosmopolitan foodborne disease that may result in severe health disorders and even death. Despite international awareness of the public health risk associated with trichinellosis, current data on its public health impact are still lacking. Therefore we assessed, for the first known time, the global burden of trichinellosis using the Disability-Adjusted Life Year metric. The global number of Disability-Adjusted Life Years due to trichinellosis was estimated to be 76 per billion persons per year (95% credible interval: 38-129). The World Health Organization European Region was the main contributor to this global burden, followed by the WHO region of the Americas and the World Health Organization Western Pacific region. The global burden of trichinellosis is much lower than that of other foodborne parasitic diseases and is in sharp contrast to the high budget allocated to prevent the disease in many industrialised countries. To decrease the uncertainty around the current estimates, more knowledge is needed on the level of underreporting of clinical trichinellosis in different parts of the world.

Detecting Trichinella infections using inverse microscopy and an improved larval counting technique

Several methods for the detection of Trichinella in meat are legally prescribed in regulation (EC) No 2075/2005, which prescribes the magnetic stirrer method for pooled sample digestion (MSM) as the reference method. However, the MSM's multistage protocol requires several preparatory steps that seem to be accountable for the loss of larvae. Here we present a modified MSM (mMSM) based on: (1) an inversion of the optical path using inverse microscopy; and (2) a modified larval counting basin (mLCB, 'Trichoview'). This enables one to examine samples of up to 40 ml and reduces the examination area from 72 to 10.3 cm2. Preparatory steps that might cause the loss of Trichinella larvae are eliminated from the new protocol. Correspondingly, the overall analytical time is reduced. In a direct and blinded comparison using 60 digest samples containing spiked vital Trichinella larvae (1-90 L1), both methods performed well for both small and large numbers of L1. However, 1278 of 1285 L1 (99.4%) were detected using the mMSM, while MSM recovered only 1225 L1 (95.3%). The improvement stems largely from samples with small numbers of L1: in all samples spiked with fewer than 10 L1, the recovery rate of mMSM was 100% compared to only 93% with MSM. Our data suggest that the use of the mMSM can improve the recovery rate by about 4% and therefore reduce the chances of a false-negative result in a sample containing 5 larvae by a factor of about 4.

Endoparasites of the raccoon dog (Nyctereutes procyonoides) and the red fox (Vulpes vulpes) in Denmark 2009-2012 - A comparative study

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Raccoon dogs recently invaded Denmark.

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Raccoon dogs and foxes harboured several helminths, some are zoonotic.

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A markedly different helminth fauna was evident between the two hosts.

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A fox was infected with Echinococcus multilocularis, no Trichinella spp. were detected.

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Wildlife surveillance is a foundation for the protection against communicable parasites.

Invasive species negatively influence the biodiversity of the ecosystems they invade and may introduce pathogens to native species. Raccoon dogs have very successfully invaded Europe, including, recently, Denmark. This study included analyses of gastrointestinal helminths and Trichinella spp. from 99 raccoon dogs and 384 native red foxes collected from October 2009 to March 2012. The sedimentation and counting method used revealed that raccoon dogs and foxes harboured 9 and 13 different helminth species, respectively, of which several known to be zoonotic. Significantly more nematode and cestode species were found in foxes while raccoon dogs had more trematode species. Rodent transmitted parasites were more prevalent in foxes, while amphibian transmitted parasites were more prevalent in raccoon dogs. One fox was infected with Echinococcus multilocularis (0.3%), while no Trichinella spp. were detected in raccoon dogs or foxes. The trematode Brachylaima tokudai was detected for the first time in Denmark in five of 384 foxes (1.3%). Prevalences of Pygidiopsis summa (3.0% and 3.4%) and Cryptocotyle spp. (15.2% and 15.4%) were comparable in raccoon dogs and foxes, respectively. Four helminth species were more prevalent in foxes than in raccoon dogs: Toxocara canis (60.9% and 13.1%); Uncinaria stenocephala (84.1% and 48.5%); Mesocestoides spp. (42.7% and 23.2%); and Taenia spp. (30.7% and 2.0%), respectively. Three helminth species were more prevalent in raccoon dogs than in foxes: Dipylidium caninum (5.1% and 0.3%); Mesorchis denticulatus (38.4% and 4.2%); and Alaria alata (69.7% and 34.4%), respectively. T. canis was more abundant in foxes while A. alata was more abundant in raccoon dogs. The intestinal distribution of a number of helminth species was comparable between hosts, but highly variable between parasite species. Inherent biological factors and host invasion of new areas might have shaped these marked differences in helminth fauna between the invasive raccoon dog and the native red fox.

One world health: socioeconomic burden and parasitic disease control priorities

Parasitic diseases present a considerable socio-economic impact to society. Zoonotic parasites can result in a considerable burden of disease in people and substantive economic losses to livestock populations. Ameliorating the effects of these diseases may consist of attempts at eradicating specific diseases at a global level, eliminating them at a national or local level or controlling them to minimise incidence. Alternatively with some parasitic zoonoses it may only be possible to treat human and animal cases as they arise. The choice of approach will be determined by the potential effectiveness of a disease control programme, its cost and the cost effectiveness or cost benefit of undertaking the intervention. Furthermore human disease burden is being increasingly measured by egalitarian non-financial measures which are difficult to apply to livestock. This adds additional challenges to the assessment of socio-economic burdens of zoonotic diseases. Using examples from the group of neglected zoonotic diseases, information regarding the socio-economic effects is reviewed together with how this information is used in decision making with regard to disease control and treatment.

How safe is the meat inspection based on artificial digestion of pooled samples for Trichinella in pork? A scenario from wildlife to a human patient in a non-endemic region of Europe

The occurrence of trichinellosis in a resident of the Netherlands prompted us to examine the likelihood of this originating from infected rats in spite of prevailing biosecurity and testing procedures. In so doing, we sought to calculate the possible risks for trichinellosis in countries deemed non-endemic. The infection risk was determined by simulating a scenario from a reservoir of minimally contaminated wildlife to pigs to humans. Results indicate that humans might become infected even in the event that artificial digestion had been performed on individually tested pig carcasses. Our conclusions justify reconsidering Trichinella control strategies based on the current testing protocol, and emphasize the importance of proper cooking as further insurance against human infection.

A bead-based suspension array for the serological detection of Trichinella in pigs

The feasibility of using bead-based suspension arrays to detect serological evidence of Trichinella in pigs was assessed. Trichinella spiralis excretory-secretory antigen was covalently coupled to paramagnetic beads and used to bind serum antibodies, which were subsequently detected using anti-swine antibody. The assay was evaluated by testing pig sera from farms where trichinellosis was endemic and comparing the results with those obtained using two commercially available ELISAs. With cut-offs established by receiver operating characteristic (ROC) analysis, digestion-negative sera from a Trichinella-free population of pigs were deemed seronegative. When anti-swine antibody was replaced with protein A/G, higher test sensitivity (94% vs. 88%) at similar test specificity (95%), was achieved. The potential use of this assay in species other than swine was also demonstrated by testing human sera.

Granulocytes in helminth infection -- who is calling the shots?

Helminths are parasitic organisms that can be broadly described as “worms” due to their elongated body plan, but which otherwise differ in shape, development, migratory routes and the predilection site of the adults and larvae. They are divided into three major groups: trematodes (flukes), which are leaf-shaped, hermaphroditic (except for blood flukes) flatworms with oral and ventral suckers; cestodes (tapeworms), which are segmented, hermaphroditic flatworms that inhabit the intestinal lumen; and nematodes (roundworms), which are dioecious, cylindrical parasites that inhabit intestinal and peripheral tissue sites. Helminths exhibit a sublime co-evolution with the host´s immune system that has enabled them to successfully colonize almost all multicellular species present in every geographical environment, including over two billion humans. In the face of this challenge, the host immune system has evolved to strike a delicate balance between attempts to neutralize the infectious assault versus limitation of damage to host tissues. Among the most important cell types during helminthic invasion are granulocytes: eosinophils, neutrophils and basophils. Depending on the specific context, these leukocytes may have pivotal roles in host protection, immunopathology, or facilitation of helminth establishment. This review provides an overview of the function of granulocytes in helminthic infections.

Policy-driven development of cost-effective, risk-based surveillance strategies

Animal health and residue surveillance verifies the good health status of the animal population, thereby supporting international free trade of animals and animal products. However, active surveillance is costly and time-consuming. The development of cost-effective tools for animal health and food hazard surveillance is therefore a priority for decision-makers in the field of veterinary public health. The assumption of this paper is that outcome-based formulation of standards, legislation leaving room for risk-based approaches and close collaboration and a mutual understanding and exchange between scientists and policy makers are essential for cost-effective surveillance. We illustrate this using the following examples: (i) a risk-based sample size calculation for surveys to substantiate freedom from diseases/infection, (ii) a cost-effective national surveillance system for Bluetongue using scenario tree modelling and (iii) a framework for risk-based residue monitoring. Surveys to substantiate freedom from infectious bovine rhinotracheitis and enzootic bovine leucosis between 2002 and 2009 saved over 6 million € by applying a risk-based sample size calculation approach, and by taking into account prior information from repeated surveys. An open, progressive policy making process stimulates research and science to develop risk-based and cost-efficient survey methodologies. Early involvement of policy makers in scientific developments facilitates implementation of new findings and full exploitation of benefits for producers and consumers.