Animal Trichinella infection in Romania: Geographical heterogeneity for the last 8 years

The First Identification of Trichinella britovi in the Raccoon Dog (Nyctereutes procyonoides) in Romania

Trichinella spp. are nematodes distributed throughout the world that affect an impressive number of host animals (mammals, birds, and reptiles) involved in the evolution of two cycles, the domestic and the sylvatic. The raccoon dog (Nyctereutes procyonoides) is an omnivorous mammal with great ecological plasticity. The expansion of the raccoon dog in Europe is associated with the risk of the introduction and spread of different pathogens, especially zoonotic ones (Trichinella, Echinococcus). Currently, the raccoon dog's range in Romania is limited to the Danube Delta area, the Lower Danube Meadow, and the Prut Meadow. The aim of this study was to examine the presence of Trichinella larvae isolated from the muscles of raccoon dog from six hunting funds of Giurgeni, Ialomița County, Romania. The muscle samples were examined via artificial digestion, and the obtained larvae were processed via multiplex PCR. The PCR-amplified ESV and ITS1 DNA fragments were then sequenced for species confirmation. The species Trichinella britovi, which is the most common species identified in wild carnivores in temperate zones, was confirmed. Although T. britovi has been reported in several host animals in Romania, this case report confirms its presence in the raccoon dog for the first time.

Trichinellosis in Hospitalized Children and Adults from Western Romania: A 11-Year Retrospective Study

Trichinellosis, a serious and sometimes fatal human disease, is a consequence of consuming raw or improperly cooked meat containing the infective larvae of Trichinella spp. The aim of this observational cohort retrospective study is to compare the epidemiological, laboratory, clinical and therapeutic aspects of trichinellosis in children and adults from Western Romania. We investigated the medical records of patients who were diagnosed with trichinellosis and hospitalized between 17 January 2010 and 31 December 2020. One hundred thirty-three patients were identified according to the electronic databases of infectious disease hospitals, located in four counties from Western Romania. A total of 19 patients (14.28%) were children and 114 patients (85.71%) were adults. In children, the most frequent symptoms were digestive in 78.94%, followed by fever in 57.89%, eyelid or facial edema in 57.89% and myalgia in 52.63% of cases, while adults presented mainly myalgia in 87.71%, followed by fever in 77.19%, digestive symptoms in 68.42% and eyelid or facial edema in 66.66% of cases. The source of infection was pork meat products in the majority of patients (89.47%). Our results revealed a general declining trend in infection rates for both children and adults during the studied period. The vast majority of cases were severe and all required hospitalization. Education of the population along with public health strategies should be improved and maintained to fully prevent trichinellosis in Western Romania.

A review of Trichinella species infection in wild animals in Romania

Nematodes of the genus Trichinella are important zoonotic parasites present throughout Romania. This study aimed to assess the status of Trichinella species in wild animals in Romania over the past 30 years. A literature review of original studies concerning the only two species (out of the four in Europe) of Trichinella (T. spiralis and T. britovi) confirmed in wildlife from Romania was conducted and corroborated with the results of our original research concerning the topic. This review article has shown that, in Romania, European minks were infected with T. spiralis, while wolves, European wild cats, Eurasian lynx, golden jackals, stone marten, and European badgers were infected with T. britovi, respectively. Both Trichinella species have been identified in foxes, bears, wild boars, and ermines, but mixed infections have been found only in European polecats. Trichinella infection is still significantly present in Romania, infecting several wild omnivorous and carnivorous species in an equal manner, with different prevalence rates over the years. Regarding the spatial distribution of T. spiralis and T. britovi in Romania, both species can be found all over the country, but in wild animals, T. britovi is the most prevalent.

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Trichinella spiralis and T. britovi have been confirmed in wild animals in Romania.

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The highest prevalence rates for Trichinella spp. have been found in wolves, bears, and foxes.

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Similar prevalence rates have been identified for T. britovi and T. spiralis in wild omnivores and carnivores.

Trichinella spp. Infection in European Polecats (Mustela Putorius Linnaeus, 1758) from Romania

The European polecat (Mustela putorius Linnaeus, 1758) is in decline in Romania, often living near human settlements, from mountains to lowlands. They feed on a wide variety of small animals, including rodents, such as mice or rats. The occurrence of this parasite in polecats from Romania was mentioned only once in 1991, but the parasite species was not confirmed by molecular biology. The study aimed to investigate the occurrence of Trichinella spp. in European polecats from Romania and to identify the parasite species by molecular tools. A total of 75 wild European polecats were examined by trichinoscopy and artificial digestion. A large number of animals were examined because of their wide distribution in Romanian territory and their presence near human settlements. For species determination, the positive muscle samples and the larvae recovered from artificial digestion were collected for DNA isolation and further processed by means of Multiplex PCR.

Only two polecats from southern Romania tested positive for Trichinella spp. infection. During trichinoscopy examination, 48 (in a polecat from Giurgiu County) and 78 (in a polecat from Ialomița County) cysts were found in the tested (56 samples/animal) tissue samples. Artificial digestion revealed infection with 2466 larvae/100 g of muscle in the polecat from Ialomița and 254/100 g in the polecat from Giurgiu. The Multiplex PCR indicated the occurrence of Trichinella spiralis in the polecat from Giurgiu and a co-infection with T. spiralis and T. britovi in the polecat from Ialomița.

The current study confirms through molecular biology, the occurrence of T. spiralis and T. britovi, as well as the occurrence of co-infection with these two Trichinella species in European polecats from Romania.

Reprint of: The European badger, Meles Meles, as a new host for Trichinella britovi in Romania

The European badger, Meles meles (Carnivora, Mustelidae) is a widespread opportunistic omnivorous mammal. Its food spectrum comprises a wide variety of plants and small animals, occasionally including rodents, such as mice or rats. Considering that rodents are known to play a key role in the life cycle of Trichinella spp., the aims of this study were to investigate the occurrence of these parasites in badgers from Romania and to identify the species. Overall, 61 badgers originating from 14 counties were examined by trichinoscopy and artificial digestion. For species determination, the positive muscle samples, and the larvae recovered from the artificial digestion were used for DNA isolation, and further processed by multiplex PCR. A single badger, originating from Sibiu County, Central Romania, was found positive for Trichinella spp. Five cysts were identified using trichinoscopy: four in the diaphragm and one in the foreleg muscles. Artificial digestion revealed an infection rate of 70 larvae/100 g of muscle. The PCR indicated the occurrence of T. britovi, which is the most commonly detected species in wild carnivores in temperate areas. Although T. britovi has previously been reported in Romania, this represents the first report of its occurrence in the European badger in the country. However, the low prevalence indicates a minor reservoir role of this species.

The European badger, Meles meles, as a new host for Trichinella britovi in Romania

The European badger, Meles meles (Carnivora, Mustelidae) is a widespread opportunistic omnivorous mammal. Its food spectrum comprises a wide variety of plants and small animals, occasionally including rodents, such as mice or rats. Considering that rodents are known to play a key role in the life cycle of Trichinella spp., the aims of this study were to investigate the occurrence of these parasites in badgers from Romania and to identify the species. Overall, 61 badgers originating from 14 counties were examined by trichinoscopy and artificial digestion. For species determination, the positive muscle samples, and the larvae recovered from the artificial digestion were used for DNA isolation, and further processed by multiplex PCR. A single badger, originating from Sibiu County, Central Romania, was found positive for Trichinella spp. Five cysts were identified using trichinoscopy: four in the diaphragm and one in the foreleg muscles. Artificial digestion revealed an infection rate of 70 larvae/100 g of muscle. The PCR indicated the occurrence of T. britovi, which is the most commonly detected species in wild carnivores in temperate areas. Although T. britovi has previously been reported in Romania, this represents the first report of its occurrence in the European badger in the country. However, the low prevalence indicates a minor reservoir role of this species.

Seroprevalance of Trichinella Spp. in Wild Boars (Sus Scrofa) from Bihor County, Western Romania

The wild boar (Sus scrofa) has a wide geographical distribution and can be an important source of Trichinella spp. infection in humans in Romania.

The objective of this study was to identify the presence of Trichinella spp. in the wild boar population in Bihor County, Romania.

Eighty four plasma and diaphragm samples, collected from wild boars, were included in this study. Artificial digestion, ELISA and Western blot were performed on these specimens. All diaphragm samples were negative for Trichinella larvae in artificial digestion, while in ELISA, 54 (64.2 %) plasma samples were positive and 6 (7.1 %) plasma samples were doubtful. Western blot was performed on 26 plasma samples from which only 6 (23.0 %) gave a positive result.

Serological evidences indicate the presence of Trichinella spp. in wild boars from western Romania. Therefore, human consumers might be at risk to ingest Trichinella larvae, even in low numbers.

Prevalence and genetic characterization of Toxoplasma gondii in naturally infected backyard pigs intended for familial consumption in Romania

BACKGROUND

Foodborne toxoplasmosis in humans can be due to the exposure to tissue cysts of Toxoplasma gondii through the consumption of meat, including pork, of infected animals. Traditional Romanian food habits include pork as the preferred meat, while backyard pig rearing remains a common practice in many rural areas of Romania. The aims of the present study were to estimate the prevalence of T. gondii infection in naturally infected backyard pigs slaughtered for familial consumption and to genetically characterize the T. gondii strains obtained.

METHODS

Paired blood and heart samples were collected from 94 backyard pigs, home slaughtered for private consumption. Serum samples were analyzed using the immunofluorescence antibody test (IFAT) for anti-T. gondii antibody detection. Heart samples were screened by polymerase chain reaction (PCR) targeting the 529-bp repeat region (REP529) for T. gondii detection. In addition, heart samples from IFAT positive animals were bioassayed in mice. The T. gondii isolates were genotyped by the analysis of 15 microsatellite markers.

RESULTS

The results showed that almost half of the pigs investigated were T. gondii seropositive (46.8%, 95% confidence interval (CI): 36.4-57.4%) and in more than a quarter of the pigs (26.6%, 95% CI: 18.0-36.7%), the parasite was detected by PCR. Three (3/44) T. gondii strains were isolated from hearts of seropositive pigs and they all belonged to genotype II.

CONCLUSIONS

The present study showed the presence of T. gondii infection in backyard pigs in Romania, which suggests that consumption of pork from animals reared and slaughtered at home may pose a potential threat to human health and should be given attention. In addition, to our knowledge, this is the first study to provide data concerning T. gondii strains circulating in pigs from Romania.

The red fox (Vulpes vulpes) plays a minor role in the epidemiology of the domestic cycle of Trichinella in Romania

Nematode worms of the genus Trichinella are zoonotic parasites with a worldwide distribution. The majority of the biomass of these nematodes circulates among wildlife, but when humans fail in the proper management of domestic animals and wildlife, Trichinella infections are transmitted from the sylvatic to the domestic environment. Such failures occur in Romania, where a high prevalence of Trichinella spiralis has been detected in domestic pigs. The aim of the present study was to provide data about the prevalence of Trichinella spp. infections in red foxes (Vulpes vulpes) that are hunted in Romanian counties, in which the prevalences of Trichinella spp. infection in backyard and free-ranging pigs range from 0.17 to 2.5%, to determine the role played by this carnivore species in the transmission of the parasite to domestic cycle. A total of 121 animals from 45 hunting grounds of three counties were screened to detect Trichinella spp. larvae by the digestion method. Infections were detected in 26 (21.5%) foxes from 18 (40%) hunting grounds of the three counties (13/67 in Arad, 1/3 in Hunedoara, and 12/51 in Timiş). The mean larval density was 10.5 larvae per gram. Of the 25 successfully tested samples, the Trichinella larvae from 24 isolates were identified as T. britovi (96%), and the larvae from one isolate were identified as T. spiralis (4%). No mixed infections were recorded. The present results revealed that the red fox should be considered an important T. britovi reservoir in the sylvatic cycle; in contrast, the detection of only a single T. spiralis-positive isolate suggests that red foxes play a minor role in the epidemiology of the domestic cycle in the investigated area of western Romania.

Epidemiology and epizootology of trichinellosis in Romania 1868-2007

According to the International Commission on Trichinellosis, Romania accounted for the most cases of trichinellosis reported worldwide in 2004. The following report summarizes the evolution of trichinellosis in Romania over a 140-year period (1868-2007). The sylvatic cycle, such as the consumption of meat from wild boar and bear, has been implicated in human cases. However, 95% of human trichinellosis cases originate from specific cultural food practices involving pork consumption. The first report of human and pig trichinellosis in Romania dates back to 1868. After the political changes of 1989, the annual incidence increased from between 0.1 and 4.1 cases per 100,000 inhabitants during the communist period (1963-1989) to 6.2 cases per 100,000 inhabitants, with a range of 2-15.9 per 100,000 between 1990 and 2007. Trichinellosis is a major public health issue in Romania that requires that policies be put forth to advance efficient prevention and control strategies.