Animal welfare and zoonosis risk: anti-Trichinella antibodies in breeding pigs farmed under controlled housing conditions.

BACKGROUND: Domesticated pigs are the main source of Trichinella sp. infections for humans, particularly when reared in backyards or free-ranging. In temperate areas of southern Europe, most pigs are farmed under controlled housing conditions, but sows and sometimes fattening pigs have access to outdoors to improve animal welfare. The aim of the present study was to investigate whether outdoor access of breeding pigs farmed under controlled housing conditions can represent a risk for Trichinella sp. transmission when the farm is located in an agricultural area interspersed with wooded areas and badlands, where Trichinella spp. could be present in wildlife. METHODS: Serum samples were collected from 63 breeding sows and one boar before and after their access to an open fenced area for 2 months and from 84 pigs that never had outdoor access. Samples were screened for anti-Trichinella antibodies by ELISA, and positive sera were confirmed using Western blot (Wb) excretory/secretory antigens. To detect Trichinella sp. larvae, muscle tissues from serologically positive and negative pigs were tested by artificial digestion. RESULTS: Thirteen (20.6%) sows and one boar tested positive with both ELISA and Wb. No larvae were detected in muscle samples of serologically positive and serologically negative pigs. Positive serum samples were then tested by Wb using crude worm extract as antigens. The Wb banding pattern displayed was that characteristic of encapsulated species (Trichinella spiralis or Trichinella britovi). CONCLUSIONS: The detection of anti-Trichinella antibodies without larvae in the pig muscles, supported by epidemiological data, suggests that pigs may have been exposed to T. britovi. This study stresses the importance of instigating monitoring systems at farm level to prevent Trichinella sp. transmission and to investigate, through a landscape parasitological study, the suitability of a site before the planting of a high containment level pig farm in which the sows can have outside access to improve their welfare during pregnancy.

Genetic evidence substantiates transmission of Trichinella spiralis from one swine farm to another.

BACKGROUND: Trichinella spiralis ranks seventh in the risk posed by foodborne parasites. It causes most human cases of trichinellosis and is the most frequent cause of Trichinella outbreaks on pig farms and in wild boar, worldwide. Veterinary inspectors seek the source of outbreaks in hopes of limiting the spread. Established molecular tools are inadequate for distinguishing among potential T. spiralis infection sources because genetic variability in these zoonotic pathogens is limited in Europe. Microsatellite markers proved successful in tracing an outbreak of T. britovi, a related parasite harboring much more genetic variation. Here, we successfully employed microsatellite markers to determine the genetic structure of T. spiralis isolates from two pig outbreaks, discovering notable uniformity among parasites within each farm and discovering an epidemiological link between these two outbreaks. METHODS: The individual larvae from five isolates of T. spiralis from two pig farms and from ten wild boars were genotyped using nine microsatellite markers to examine their genetic structure. RESULTS: Notably uniform parasite populations constituted each farm outbreak, and the parasites from the first and second outbreaks resembled each other to a notable degree, indicating an epidemiological link between them. Wild boar harbored more genetically variable larval cohorts, distinguishing them from parasites isolated from domestic pigs. CONCLUSIONS: Microsatellite markers succeeded in distinguishing isolates of the highly homogeneous T. spiralis, aiding efforts to track transmission. Each outbreak was composed of a homogenous group of parasites, suggesting a point source of contamination.

A review on Trichinella infection in South America.

Trichinella spp. causes human trichinellosis by means of the consumption of raw or inadequately treated meat from domestic or game animals. In the Americas, as well as in other continents, Trichinella infection is a health issue for humans and has a negative impact on the pork meat market, generated by people's fear of becoming infected with the parasite. The distribution of human cases and the sources of this disease in humans and animals were analysed in this report, which summarizes the information available regarding Trichinella infection in animals and humans in South America. Within South America, human infection with Trichinella was documented in Argentina and Chile during the period 2005-2019. Trichinellosis is endemic in these countries for, with human cases and foci in domestic and wild animals. In Argentina, human cases occur throughout the country, with foci found in pigs and wild animals. In Argentina, during the period 2012-2018, the number of suspected human cases reached 6,662. T. spiralis was identified in one South American sea lion (Otaria flavescens) from Patagonia, Argentina, for the first time in the region in 2018. In Chile, 258 human cases of trichinellosis were confirmed during the period 2005-2015; out of those 258 cases, most samples which tested positive for Trichinella spp. (29.5%) were detected in the Metropolitan district (Santiago de Chile and outskirts), and 17.4% in The Lake district. Regarding age brackets, people between 30-49 years of age showed the most cases (40.1%). In Brazil, the infection is absent in domestic species but it has been found in wild boars (Sus scrofa) but limited to one or more region of the country. Within the animal species destined for food in South America, those that showed higher parasitical loads were pigs and wild boars, while armadillos (Chaetophractus villosus) and peccaries (Tayassu tajacu) showed very low Trichinella spp. larvae loads (0.04 - 0.1 larvae/g). Antibodies against Trichinella spp. have been detected in pigs from Ecuador and Bolivia. In Bolivia, antibodies were also found in humans. Peru, Colombia and Uruguay have no documented presence of Trichinella spp. in animals and humans. There is insufficient information regarding the presence of Trichinella spp. in domestic and wild animals, as well as in humans, since only a very limited number of surveys have been carried out. No papers with information on Trichinella spp. circulating in animals or humans have been published regarding the situation in Guyana, Surinam, French Guiana, Venezuela and Paraguay. Considering the growth of the guinea pig meat market in the Andean region, and the high prevalence of the disease reported in free range pigs and wild boars, as well as other game animal species, it is important to focus on the role of biosecurity and risk management, while improving meat market regulations, and detection of infection prior to consumption, in order to reduce the risk of transmission of this zoonotic disease to humans.

Epidemiology and hypothetical transmission cycles of Trichinella infections in the Greater Kruger National Park of South Africa: an example of host-parasite interactions in an environment with minimal human interactions.

Knowledge on the epidemiology, host range and transmission of Trichinella spp. infections in different ecological zones in southern Africa including areas of wildlife-human interface is limited. The majority of reports on Trichinella infections in sub-Saharan Africa were from wildlife resident in protected areas. Elucidation of the epidemiology of the infections and the prediction of hosts involved in the sylvatic cycles within specific ecological niches is critical. Of recent, there have been reports of Trichinella infections in several wildlife species within the Greater Kruger National Park (GKNP) of South Africa, which has prompted the revision and update of published hypothetical transmission cycles including the hypothetical options based previously on the biology and feeding behaviour of wildlife hosts confined to the GKNP. Using data gathered from surveillance studies and reports spanning the period 1964-2019, confirmed transmission cycles and revised hypothesized transmission cycles of three known Trichinella species (T. zimbabwensis, Trichinella T8 and T. nelsoni) are presented. These were formulated based on the epidemiological factors, feeding habits of hosts and prevalence data gathered from the GKNP. We presume that the formulated sylvatic cycles may be extrapolated to similar national parks and wildlife protected areas in sub-Saharan Africa where the same host and parasite species are known to occur. The anecdotal nature of some of the presented data confirms the need for more intense epidemiological surveillance in national parks and wildlife protected areas in the rest of sub-Saharan Africa to unravel the epidemiology of Trichinella infections in these unique and diverse protected landscapes.

TITLE: Épidémiologie et cycles de transmission hypothétiques des infections à Trichinella dans le Grand Parc National Kruger en Afrique du Sud : un exemple d'interactions hôtes-parasites dans un environnement où les interactions humaines sont minimales. ABSTRACT: Les connaissances sur l'épidémiologie, la gamme d'hôtes et la transmission des infections à Trichinella spp. dans différentes zones écologiques d'Afrique australe, y compris les zones d'interface faune-homme, sont limitées. La majorité des signalements d'infections à Trichinella en Afrique subsaharienne proviennent animaux sauvages résidant dans des zones protégées. L'élucidation de l'épidémiologie des infections et la prévision des hôtes impliqués dans les cycles sylvatiques au sein de niches écologiques spécifiques sont essentielles. Récemment, des infections à Trichinella ont été signalées chez plusieurs espèces sauvages dans le Grand Parc National Kruger (GPNK) en Afrique du Sud, ce qui a incité à la révision et à la mise à jour des cycles de transmission hypothétiques publiés, y compris les options hypothétiques basées précédemment sur la biologie et le comportement alimentaire des hôtes de la faune sauvage confinés au GPNK. À partir des données des études de surveillance et de rapports couvrant la période 1964­2019, les cycles de transmission confirmés et les cycles de transmission hypothétiques révisés de trois espèces connues de Trichinella (T. zimbabwensis, Trichinella T8 et T. nelsoni) sont présentés. Ceux-ci ont été formulés sur la base des facteurs épidémiologiques, des habitudes alimentaires des hôtes et des données de prévalence recueillies au GPNK. Nous supposons que les cycles sylvatiques formulés peuvent être extrapolés aux parcs nationaux et zones protégées similaires en Afrique subsaharienne, où les mêmes hôtes et espèces de parasites sont connues. La nature anecdotique de certaines des données présentées confirme la nécessité d'une surveillance épidémiologique plus intense dans les parcs nationaux et zones protégées du reste de l'Afrique subsaharienne pour démêler l'épidémiologie des infections à Trichinella dans ces paysages protégés uniques et diversifiés.

Early diagnosis of experimental Trichinella spiralis infection by nano-based enzyme-linked immunosorbent assay (nano-based ELISA).

Trichinellosis is a serious foodborne zoonotic disease. It is an important threat to public health all over the world. Although anti-Trichinella IgG detection is the most widely used method for diagnosis of trichinellosis, but there is an obvious window between clinical symptoms and positive serology. Gold nanoparticles (AuNPs) can be conjugated with antibodies affording them promising applications for bio-chemical detection. Herein, AuNPs-based ELISA was evaluated for the first time in the detection of Trichinella spiralis circulating antigen (CAg) for its potential as a diagnostic tool of experimental infection. Swiss Albino mice were orally inoculated with 100 muscle larvae/mouse. Animals were sacrificed 6, 8, 10, 12, 14, 16, 22 and 28 day-post infection (dpi). Blood samples were tested for CAg by both standard ELISA and nano-based ELISA using anti-rabbit polyclonal IgG conjugated with AuNPs. CAg was only detected by nano-based ELISA 6, 8, 10 dpi and by both formats 12-28 dpi. Nano-based assay recorded a statistically significant high sensitivity (58.33%, 91.67%) and accuracy (72.22%, 94.44%) 8 and 10 dpi, respectively in comparison to standard ELISA. Both assays showed high sensitivity and accuracy 12-28 dpi. Thus, nano-based ELISA could be considered as an early sensitive diagnostic method for experimental trichinellosis.

Development of genome-wide polymorphic microsatellite markers for Trichinella spiralis.

BACKGROUND: Trichinella nematodes are globally distributed food-borne pathogens, in which Trichinella spiralis is the most common species in China. Microsatellites are a powerful tool in population genetics and phylogeographic analysis. However, only a few microsatellite markers were reported in T. spiralis. Thus, there is a need to develop and validate genome-wide microsatellite markers for T. spiralis. METHODS: Microsatellites were selected from shotgun genomic sequences using MIcroSAtellite identification tool (MISA). The identified markers were validated in 12 isolates of T. spiralis in China. RESULTS: A total of 93,140 microsatellites were identified by MISA from 9267 contigs in T. spiralis genome sequences, in which 16 polymorphic loci were selected for validation by PCR with single larvae from 12 isolates of T. spiralis in China. There were 7-19 alleles per locus (average 11.25 alleles per locus). The observed heterozygosity (HO) and expected heterozygosity (HE) ranged from 0.325 to 0.750 and 0.737 to 0.918, respectively. The polymorphism information content (PIC) ranged from 0.719 to 0.978 (average 0.826). Among the 16 loci, markers for 10 loci could be amplified from all 12 international standard strains of Trichinella spp. CONCLUSIONS: Sixteen highly polymorphic markers were selected and validated for T. spiralis. Primary phylogenetic analysis showed that these markers might serve as a useful tool for genetic studies of Trichinella parasites.

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.

[Trichinellosis outbreaks in Aragón (1998-2017)]. / Brotes epidémicos de triquinosis ocurridos en Aragón durante el periodo 1998 ­ 2017.

OBJECTIVE: In Aragon, official veterinary controls to detect the presence of Trichinella in meat products have allowed trichinosis to be a low-incidence disease in the form of outbreaks associated with family consumption of meat products that are not sanitarily controlled. The aim of the work was to describe the epidemiological characteristics of the trichinosis outbreaks that occurred in Aragon during the study period and the action measures carried out, which served as a basis for redesigning and strengthening prevention and control measures. METHODS: Descriptive study of the characteristics of time, place, person, food implicated, etiological agent and control measures implemented in the outbreaks identified by the Epidemiological Surveillance Network of Aragón from 01/01/1998 to 31/12/2017. For the descriptive analysis, the mean with its standard deviation and proportions were calculated. RESULTS: During the study period (from 01/01/1998 until 31/12/2017) there were 7 family outbreaks with 294 exposed, 103 cases (Attack Rate 35%), of which 29 were hospitalized (28.1%). The case fatality rate was 1%. The average age of the cases was 43.3 years (standard deviation 15.9). 70.8% of the cases were male. Outbreaks were concentrated between December and May. Five outbreaks originated after consumption of wild boar. The etiological agent identified in meat and/or biological samples from the cases was Trichinella spiralis in four outbreaks and Trichinella britovi in two other outbreaks, while the agent could not be identified in one outbreak. In all outbreaks, actions were carried out in accordance with the recommendations established by the National Epidemiological Surveillance Network (RENAVE). CONCLUSIONS: Trichinosis in Aragon takes the form of sporadic family outbreaks coinciding with the time of wild boar hunting and home slaughtering of pigs and is associated with the consumption of meat products not controlled sanitarily, so it is necessary to strengthen health education and intersectoral collaboration in the development and implementation of prevention and control strategies.

OBJETIVO: En Aragón, los controles oficiales veterinarios para detectar la presencia de triquina en productos cárnicos, han permitido que la triquinosis sea una enfermedad de baja incidencia, que se presenta en forma de brotes, asociados al consumo familiar de productos cárnicos no controlados sanitariamente. El objetivo del trabajo fue describir las características epidemiológicas de los brotes de triquinosis ocurridos en Aragón durante el periodo de estudio y las medidas de actuación llevadas a cabo, lo que sirvió de base para rediseñar y fortalecer las medidas de prevención y control. METODOS: Estudio descriptivo de las características tiempo, lugar, persona, alimentos implicados, agente etiológico y medidas de control implementadas en los brotes identificados por la Red de Vigilancia Epidemiológica de Aragón desde el 01/01/1998 al 31/12/2017. Para el análisis descriptivo se calcularon la media con su desviación estándar y las proporciones. RESULTADOS: Durante el periodo de estudio (desde el 01/01/1998 hasta el 31/12/2017) se declararon 7 brotes familiares con 294 expuestos, 103 casos (Tasa de Ataque 35%), de los que 29 fueron hospitalizados (28,1%). La tasa de letalidad fue del 1%. La media de edad de los casos fue de 43,3 años (desviación típica 15,9). El 70,8% de los casos fueron varones. Los brotes se concentraron entre diciembre y mayo. Cinco brotes se originaron tras el consumo de jabalí. El agente etiológico aislado en muestras cárnicas y/o muestras biológicas procedentes de los casos, fue Trichinella spiralis en cuatro brotes y Trichinella britovi en otros dos brotes. En todos los brotes las actuaciones se realizaron conforme a las recomendaciones establecidas por la Red Nacional de Vigilancia Epidemiológica (RENAVE). CONCLUSIONES: La triquinosis en Aragón se presenta en forma de brotes familiares esporádicos coincidentes con la época de caza de jabalí y matanza domiciliaria del cerdo y se asocia al consumo de productos cárnicos no controlados sanitariamente, por lo que es necesario reforzar la educación para la salud y la colaboración intersectorial en la elaboración e implantación de estrategias de prevención y control.

Occurrence of Trichinella spp. in rats on pig farms.

INTRODUCTION: The highest risk of trichinellosis for human is considered in eating meat products containing live larvae, mostly from wild boars or pigs. Spreading of Trichinella spp. may occur in various ways, one of which is transmission by vectors. The rat is considered to be the most common vector for Trichinella parasite. The population of rats living on pig farms can play an important role in maintaining or spreading the parasite to other animals. OBJECTIVE: The aim of presented survey was to investigate the occurrence of Trichinella spp. in rats on farms with pigs infected with this parasite. MATERIAL AND METHODS: From pig farms selected for study, the muscles of collected rats were investigated by magnetic stirrer digestion method to assess occurrence of Trichinella in the rat population. Isolated Trichinella parasites were identified under stereomicroscope and multiplex PCR were performed for species identification. RESULTS: Rats infected with Trichinella spp. were discovered on three of five investigated pig farms. The mean extent of invasion in rats from the studied farms was 23.33%. The calculated medium intensity of invasion was 4.09 lpg (larvae per gram) (SD 5.41). All larvae of Trichinella discovered from rats were identified as T.spiralis. CONCLUSIONS: The results obtained indicate that in farms with a high prevalence of Trichinella invasion in pigs there are very likely to be found rats infected by this nematode. This suggests possibility to maintain the invasion in herd and spread into neighborhood farms.

Outbreak of Trichinella T9 Infections Associated with Consumption of Bear Meat, Japan.

An outbreak of trichinellosis occurred in Japan in December 2016. All case-patients had eaten undercooked bear meat, from which Trichinella larvae were subsequently isolated. DNA sequencing analysis of the mitochondrial genes cytochrome c-oxidase subunit 1 and internal transcribed spacer 2 confirmed that Trichinella T9 had caused the outbreak.

Conocimientos y prácticas asociadas a transmisión de triquinelosis, hanta y equinococosis quística / Knowledge and practices associated with transmission of trichinellosis, hanta and cystic equinococcosis

RESUMEN Objetivo: Asociar el nivel de conocimiento y prácticas (hábitos y costumbres) responsables de la transmisión de Triquinelosis, Síndrome Cardiopulmonar por Hantavirus y Equinococosis quística (Hidatidosis), en habitantes de los sectores rurales. Material y método: Estudio descriptivo correlacional de corte transversal en el que se aplicó una encuesta a 149 habitantes residentes en el área rural de las localidades de Curacautín, Lonquimay y Melipeuco, a través de muestreo no probabilístico por conveniencia, durante los meses de diciembre 2013 a enero 2014. Resultados: La población posee mejores conocimientos de Triquinelosis y Hanta que Hidatidosis, 64,9, 72,8 y 39,3%, respectivamente; los hábitos y costumbres para Hanta e Hidatidosis alcanzan mejores prácticas (84% cada una) que para Triquinelosis (69,5%); la población reconoce correctamente reservorio, fuente de infección y mecanismos de transmisión en Triquinelosis y Hanta, pero en menor grado Hidatidosis; respecto de los hábitos y costumbres, aun desconociendo los fundamentos teóricos, reportan buenas prácticas, aunque mantienen algunas que favorecen la transmisión de infecciones predominantemente en Triquinelosis. Conclusión: El nivel de conocimiento no asegura buenas prácticas, además los conocimientos y prácticas siguen un patrón empírico más que cognitivo, respaldados por aspectos culturales y del entorno. Esto sugiere mayor participación de los equipos interdisciplinarios en comunidades aisladas para fortalecer la promoción, educación y refuerzo de las buenas prácticas de acuerdo con sus condiciones sociales e incentivar la adherencia a conductas que reduzcan el riesgo de la transmisión de zoonosis.

ABSTRACT Objective: To associate the level of knowledge and practices (habits and customs) responsible for the transmission of trichinellosis, Hanta and cystic echinococcosis (hydatidosis), among rural population. Material and method: Cross-sectional correlational descriptive study in which 149 residents of the rural areas of Curacautín, Lonquimay and Melipeuco were surveyed, using non-probability convenience sampling from December 2013 to January 2014. Results: The population has better knowledge of trichinellosis and Hanta than hydatidosis, 64.9%, 72.8 and 39.3% respectively; they also have better practices regarding Hanta and hydatidosis (84% each) than regarding trichinellosis (69.5%). The population recognizes correctly the reservoir, source of infection and transmission mechanisms of trichinellosis and Hanta, and to a lesser degree hydatidosis; they report good practices regarding habits and customs, even ignoring theoretical foundations, but maintain some practices that favor the transmission of infections related to trichinellosis. Conclusion: The level of knowledge does not ensure good practices. Additionally, knowledge and practices follow an empirical rather than cognitive pattern, rooted on cultural and environmental aspects. This suggests greater participation of interdisciplinary teams in isolated communities to strengthen the promotion, education and reinforcement of good practices in accordance with their social conditions and to encourage adherence to behaviors that reduce the risk of the transmission of zoonoses.

A synoptic overview of golden jackal parasites reveals high diversity of species.

The golden jackal (Canis aureus) is a species under significant and fast geographic expansion. Various parasites are known from golden jackals across their geographic range, and certain groups can be spread during their expansion, increasing the risk of cross-infection with other carnivores or even humans. The current list of the golden jackal parasites includes 194 species and was compiled on the basis of an extensive literature search published from historical times until April 2017, and is shown herein in synoptic tables followed by critical comments of the various findings. This large variety of parasites is related to the extensive geographic range, territorial mobility and a very unselective diet. The vast majority of these parasites are shared with domestic dogs or cats. The zoonotic potential is the most important aspect of species reported in the golden jackal, some of them, such as Echinococcus spp., hookworms, Toxocara spp., or Trichinella spp., having a great public health impact. Our review brings overwhelming evidence on the importance of Canis aureus as a wild reservoir of human and animal parasites.

Studies on vertical transmission of Trichinella spiralis in experimentally infected guinea pigs (Cavia porcellus).

An experimental study to enhance knowledge on the capability of Trichenella spiralis to pass from guinea pigs to progeny at different periods of pregnancy or lactation was performed. For this purpose, 18 female adult guinea pigs were inoculated with 100 or 1000 T. spiralis muscle larvae (ML) during early, late gestation and during lactation period. The presence of T. spiralis (ML) in mothers and newborns was studied through enzymatic digestion from muscle samples. ML were observed in 9 of 42 newborn guinea pigs and levels of infection were significantly higher when infections of mothers were done during late gestation (p = 0.0046) with the high infective dose (p = 0.0043). T. spiralis ML were not recovered from any of the newborns from mothers infected in the lactation period. Ten out of 18 infected mothers presented larvae 1 in their mammary glands. Muscle samples from the tongue and the masseter showed the highest larval burdens. These observations confirm previous reports on that ML of T. spiralis are capable to pass through placental tissues to reach and encyst in striated muscle groups of newborn guinea pigs. This study may also reinforce the importance of preventive programs to control trichinellosis in those endemic areas where pregnant women would have high risk of infection.

Trichinella and polar bears: a limited risk for humans.

In this review, we identified 63 cases reported since World War II of human trichinellosis linked to the consumption of parasitized polar bear (Ursus maritimus) meat. This low number contrasts to the numerous cases of human trichinellosis related to consumption of the meat of black (U. americanus) or brown bears (U. arctos). The prevalence of Trichinella infection is high in bears, but larval muscular burden is usually lower in polar bears compared to other bear species. Polar bears, therefore, seem to play a limited role in the transmission of trichinellosis to humans, as native residents living in the Arctic traditionally consume well-cooked bear meat, and travellers and foreign hunters have only limited access to this protected species due to the declining polar bear population.

Trichinellosis outbreak due to wild boar meat consumption in southern Italy.

We report a Trichinella britovi outbreak investigated during February-March 2016 in southern Italy. The source of infection was meat from infected wild boars that were illegally hunted and, hence, not submitted to post-mortem veterinary inspection. Thirty persons reported having eaten raw dried homemade sausages; five cases of trichinellosis were confirmed. Wild game meat consumers need to be educated about the risk for trichinellosis.

Meat sources of infection for outbreaks of human trichinellosis.

Trichinellosis is one of the most important foodborne zoonotic diseases, with worldwide distribution. While human risk for trichinellosis has historically been linked to pork, modern pork production systems and slaughter inspection programs have reduced or eliminated pork as a source for trichinellosis in many countries. While pork may no longer pose a significant risk for trichinellosis, many other animal species may be hosts for Trichinella species nematodes and when human consume meat from these animal species, there may be risk for acquiring trichinellosis. This review article describes the various non-pork meat sources of human trichinellosis outbreaks, where these outbreaks have occurred and some of the factors that contribute to human risk. The literature reviewed here provides evidence of the persistence of Trichinella as a human health risk for people who eat meat from feral and wild carnivores and scavengers, as well as some herbivores that have been shown to harbor Trichinella larvae. It points to the importance of education of hunters and consumers of these meats and meat products.

Parasite to patient: A quantitative risk model for Trichinella spp. in pork and wild boar meat.

Consumption of raw or inadequately cooked pork meat may result in trichinellosis, a human disease due to nematodes of the genus Trichinella. In many countries worldwide, individual control of pig carcasses at meat inspection is mandatory but incurs high costs in relation to absence of positive carcasses from pigs reared under controlled housing. EU regulation 2015/1375 implements an alternative risk-based approach, in view of absence of positive findings in pigs under controlled housing conditions. Moreover, Codex Alimentarius guidelines for the control of Trichinella spp. in meat of suidae have been published (CAC, 2015) and used in conjunction with the OIE terrestrial Animal health code, to provide guidance to governments and industry on risk based control measures to prevent human exposure to Trichinella spp. and to facilitate international pork trade. To further support such a risk-based approach, we model the risk of human trichinellosis due to consumption of meat from infected pigs, raised under non-controlled housing and wild boar, using Quantitative Microbial Risk Assessment (QMRA) methods. Our model quantifies the distribution of Trichinella muscle larve (ML) in swine, test sensitivity at carcass control, partitioning of edible pork parts, Trichinella ML distribution in edible muscle types, heat inactivation by cooking and portion sizes. The resulting exposure estimate is combined with a dose response model for Trichinella species to estimate the incidence of human illness after consumption of infected meat. Paramater estimation is based on experimental and observational datasets. In Poland, which served as example, we estimated an average incidence of 0.90 (95%CI: 0.00-3.68) trichinellosis cases per million persons per year (Mpy) due to consumption of pork from pigs that were reared under non-controlled housing, and 1.97 (95%CI: 0.82-4.00) cases per Mpy due to consumption of wild boar. The total estimated incidence of human trichinellosis attributed to pigs from non-controlled housing and wild boar in Poland, is similar to the incidence of human trichinellosis in that country reported by EFSA. Overall, in Europe, we estimated an upper incidence limit of 5.3×10-4 cases per Mpy, or less than one predicted case of trichinellosis in the European Union every 4years, due to consumption of pork from controlled housing. Therefore, Trichinella testing of pigs under controlled housing is not adding any value to protect human health. We suggest applying our farm-to-fork QMRA model to further support decision making on the global scale.

[Knowledge and practices regarding cystic echinococcosis and trichinellosis in users and companions of users of the Hospital Comunitario de Salud Familiar El Carmen, Biobio Region, Chile]. / Conocimientos y prácticas sobre hidatidosis y triquinosis en usuarios y acompañantes del Hospital Comunitario de Salud Familiar El Carmen, Región del Biobío, Chile.

We surveyed users of the Hospital Comunitario de Salud Familiar El Carmen and their companions to analyze knowledge and practices regarding cystic echinococcosis and trichinellosis. Most people recognized risky practices. Previous attendance at talks and working in agricultural-livestock enhanced the knowledge. Age, sex and formal education were not associated with the knowledge. Knowledge was not associated with practices.