[Show abstract][Hide abstract] ABSTRACT: There is an increasing reporting of Anisakiasis in humans at the world level and this disease has become a concern for the public health and for the fish and derived product trade. Humans acquire the infection by the ingestion of live larvae present in raw or almost raw (e.g., marinate, salted) fish products if the processing is insufficient to devitalize the worms. The aim of this study was to asses a dry salting process in killing Anisakis pegreffii larvae in naturally infected European anchovies (Engraulis encrasicolus) and to evaluate the quality assessment. The results show that a dry salting process with a salt concentration of 21% in all parts of the anchovy fillets devitalize A. pegreffii larvae in a 15 day period. The finished product showed a good panel acceptance and anchovies reached a good quality grade.
[Show abstract][Hide abstract] ABSTRACT: Trichinella spp. are zoonotic parasites transmitted to humans by the consumption of raw or insufficiently cooked meat of different animal species. The most common source of infection for humans is meat from pigs and wild boar (Sus scrofa). The aim of the present work was to evaluate the incidence of Trichinella spp. infections in wild boar hunted in Latvia over a 38 year interval (1976 to 2013).
A total 120,609 wild boars were individually tested for Trichinella spp. by trichinoscopy and, in case of negativity, by artificial digestion of 25 g muscles, in the 1976-2005 period, and by artificial digestion of 25-50 g muscles in the 2006-2013 period. Trichinella spp. larvae were identified at the species level by multiplex PCR.
In the study period, the overall prevalence of infected wild boar was 2.5%. Trichinella britovi was the predominant (90%) species. The incidence of Trichinella spp. infection in wild boar exhibited two different trends. From 1976 to 1987, the incidence of infected/hunted wild boar increased from 0.23% to 2.56%, then it decreased to 0.19 in 1994. Thereafter, the incidence fluctuated between 0.05% and 0.37%. A statistically significant (P < 0.05) correlation (r = 0.54; p = 0.0199) was found between the trend of Trichinella spp. incidence in hunted wild boar and the number of snow cover days from 1976 to 1993. From 1997 to 2013, the estimated wild boar population of Latvia increased by 4.9 times and the hunting bag by 9.7 times, with a stable incidence of Trichinella spp. in the population. It follows that the biomass of Trichinella spp. larvae and of T. britovi, in particular, increased.
The incidence trends of Trichinella spp. in wild boar could be related to the role played by the snow in reducing the thermal shock and muscle putrefaction which increases the survival of the larvae in muscle tissues of carrion in the 1976-1993 period; and, in the 1997-2013 period, to the increased biomass of Trichinella spp. due to the increased carnivore populations, which are the main reservoirs of these parasites.
Full-text · Article · Dec 2015 · Parasites & Vectors
[Show abstract][Hide abstract] ABSTRACT: Several species of protozoa cause acute or chronic gastroenteritis in humans, worldwide. The burden of disease is particularly high among children living in developing areas of the world, where transmission is favored by lower hygienic standards and scarce availability of safe water. However, asymptomatic infection and polyparasitism are also commonly observed in poor settings. Here, we investigated the prevalence of intestinal protozoa in two small fishing villages, Porto Said (PS) and Santa Maria da Serra (SM), situated along the river Tietê in the State of São Paolo, Brazil. The villages lack basic public infrastructure and services, such as roads, public water supply, electricity and public health services.
Multiple fecal samples were collected from 88 individuals in PS and from 38 individuals in SM, who were asymptomatic at the time of sampling and had no recent history of diarrheal disease. To gain insights into potential transmission routes, 49 dog fecal samples (38 from PS and 11 from SM) and 28 river water samples were also collected. All samples were tested by microscopy and PCR was used to genotype Giardia duodenalis, Blastocystis sp., Dientamoeba fragilis and Cryptosporidium spp.
By molecular methods, the most common human parasite was Blastocystis sp. (prevalence, 45% in PS and 71% in SM), followed by D. fragilis (13.6% in PS, and 18.4% in SM) and G. duodenalis (18.2% in PS and 7.9% in SM); Cryptosporidium spp. were not detected. Sequence analysis revealed large genetic variation among Blastocystis samples, with subtypes (STs) 1 and 3 being predominant, and with the notable absence of ST4. Among G. duodenalis samples, assemblages A and B were detected in humans, whereas assemblages A, C and D were found in dogs. Finally, all D. fragilis samples from humans were genotype 1. A single dog was found infected with Cryptosporidium canis. River water samples were negative for the investigated parasites.
This study showed a high carriage of intestinal parasites in asymptomatic individuals from two poor Brazilian villages, and highlighted a large genetic variability of Blastocystis spp. and G. duodenalis.
Full-text · Article · Dec 2015 · Parasites & Vectors
[Show abstract][Hide abstract] ABSTRACT: Considering that the current immunoassays are not able to distinguish the infective forms that cause Toxoplasma gondii infection, the present study was carried out to evaluate the reactivity of two recombinant proteins (CCp5A and OWP1) from oocyst/sporozoite, in order to differentiate infections occurring by ingestion of oocysts or tissue cysts. The reactivity of the recombinant proteins was assessed against panels of serum samples from animals (chickens, pigs, and mice) that were naturally or experimentally infected by different infective stages of the parasite. Also, we tested sera from humans who have been infected by oocysts during a well-characterized toxoplasmosis outbreak, as well as sera from pregnant women tested IgM+/IgG+ for T. gondii, which source of infection was unknown. Only the sporozoite-specific CCp5A protein was able to differentiate the parasite stage that infected chickens, pigs and mice, with specific reactivity for oocyst-infected animals. Furthermore, the CCp5A showed preferential reactivity for recent infection by oocyst/sporozoite in pigs and mice. In humans, CCp5A showed higher reactivity with serum samples from the outbreak, compared with serum from pregnant women. Altogether, these findings demonstrate the usefulness of the CCp5A protein as a new tool to identify the parasite stage of T. gondii infection, allowing its application for diagnosis and epidemiological investigations in animals and humans. The identification of parasite infective stage can help to design effective strategies to minimize severe complications in immunocompromised people and, particularly, in pregnant women to prevent congenital infection.
Full-text · Article · Nov 2015 · Frontiers in Microbiology
[Show abstract][Hide abstract] ABSTRACT: Trichinellosis is a zoonotic disease caused by Trichinella muscle larvae (ML) through ingestion of raw or undercooked meat. To date, 12 taxa are recognized in this genus, of which four are circulating in Europe (Trichinella spiralis, Trichinella nativa, Trichinella britovi and Trichinella pseudospiralis). T. spiralis and T. britovi circulate in European wildlife and occur simultaneously in the same host species. The possibility of hybrid formation between T. britovi and T. spiralis has hardly been addressed and so far, results of experimental hybridisation attempts between T. britovi and T. spiralis are inconclusive. The aim of the present study was to analyse molecular polymorphisms of single T. spiralis and T. britovi (ML) from natural infections based on nuclear 5S rDNA intergenic spacer region (5S rDNA-ISR) and mitochondrial cytochrome c oxidase 1 (CO1) gene sequences. Six haplotypes of the 5S rDNA intergenic spacer region (5S rDNA-ISR) and 14 of the cytochrome c oxidase 1 (CO1) gene were demonstrated in 89 individual T. britovi ML from Latvia and Poland. In contrast, only two haplotypes were observed at both 5S rDNA-ISR and CO1 of 57 individual T. spiralis ML from Polish wild boar and red foxes. Moreover, this study demonstrates hybridisation in eight individual ML between T. britovi and T. spiralis under natural conditions in four Polish wild boar and two red foxes, revealed by combining 5S rDNA-ISR and CO1 sequence information of individual Trichinella ML. To our knowledge, this is the first report of interspecies hybridisation between T. spiralis and T. britovi under field conditions.
Full-text · Article · Oct 2015 · Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases
[Show abstract][Hide abstract] ABSTRACT: To investigate the spatial distribution of the Trichinella spp. and the factors influencing their circulation in Hungary, 4086 red foxes (Vulpes vulpes) and 0.32 million wild boars (Sus scrofa) were tested for Trichinella spp. infection in Hungary from 2006 to 2014. Trichinella spp. larvae from 86 (2.1%) foxes and 58 (0.02%) wild boars were identified by multiplex PCR as Trichinella britovi, Trichinella spiralis or Trichinella pseudospiralis. T. britovi was the dominant species in both foxes and wild boars (87.5% and 67.3%) followed by T. spiralis (11.2% and 31.0%) and T. pseudospiralis (1.3% and 1.7%). There was no correlation between environmental parameters in the home range of foxes and wild boars and the T. spiralis larval counts, but there was a positive correlation between the boundary zone of Hungary and T. spiralis infection. These results indicate that the distribution of T. spiralis in the Hungarian wildlife is determined by the transborder transmission of the parasite from the surrounding endemic countries. Based on the statistical analysis, non-agricultural areas and the mean annual temperature were the major determinants of the spatial distribution of T. britovi in Hungary. The positive relationship with non-agricultural areas can be explained by the generalist feeding behaviour including scavenging of foxes in these areas. The negative relationship with the mean annual temperature can be attributed to the slower decomposition of wildlife carcasses favouring a longer survival of T. britovi larvae in the host carrion and to the increase of scavenging of foxes.
Full-text · Article · Aug 2015 · Magyar Allatorvosok Lapja
[Show abstract][Hide abstract] ABSTRACT: Human alveolar echinococcosis, caused by the tapeworm Echinococcus multilocularis, is the most pathogenic parasitozoonosis in the temperate and arctic region of Europe. E. multiloculoris adult worms were detected in foxes of 16 Hungarian counties and in the suburban areas of the captial, Budapest. The prevalence of infection was 10.7% and 7.9%, the intensity of infection was 746 and 243 worms/fox in 2008-2009 and 2012-2013, respectively. The spatial distribution of the parasite was highly clumped; the majority of infected foxes came from the Northern Mountain Range and northern part of Transdanubia. The multi-locus microsatellite analysis of the worms indicate that Hungary should be considered as a peripheral area of a single European focus, where the dispersal movement of foxes resulted in the spreading of the parasite from one county to another within a time period short enough to avoid a substantial genetic drift. Based on geographic information system based analysis, mean annual temperature and annual precipitation were the major determinants of the spatia distribution of E. multiloculoris in Hungary. It can be attributed to the sensitivity of E. multiloculoris eggs to high temperatures and desiccation. Although spreading and emergence of the parasite was observed in Hungary before 2009, the prevalence and intensity of infection did not change significantly betwen the two collection periods. It can be explained by the considerably lower annual precipitation before the second collection period.
Full-text · Article · Jul 2015 · Magyar Allatorvosok Lapja
[Show abstract][Hide abstract] ABSTRACT: The European Union Reference Laboratory for Parasites (EURLP) organises proficiency testing (PT) for the National Reference Laboratories for Parasites (NRLs) of the member states and for public and private laboratories performing official controls in European and extra-EU countries, in order to assess their competence and to improve laboratory performance. Since its appointment in July 2006, the EURLP organised almost 50 PTs on different methods to detect and identify foodborne parasites. According to the Commission Regulation (EC) 2075/2005, all animals which are potential carriers of Trichinella spp. larvae, shall be tested at the slaughterhouse by one of the methods reported in the Regulation 2075/2005. The EURLP organised eight PTs (once a year) on detection of Trichinella larvae in a panel of meat balls, made by minced pork or horse meat spiked with Trichinella larvae. Moreover, PTs on the identification of Trichinella parasites by molecular methods were organised; samples consisted of Trichinella larvae preserved in 95 % ethanol. The EURLP organised PTs to test the competence of NRLs to detect Anisakidae larvae in fish fillets. PTs were also organised to test the competence of NRLs to detect Echinococcus sp. worms or their parts in the intestinal mucosa of canids, definitive hosts of these parasites. All PTs were qualitatively evaluated; a quantitative evaluation was also performed, when appropriate, in order to provide participants with a useful tool to improve their performance.
Full-text · Article · Jun 2015 · Accreditation and Quality Assurance
[Show abstract][Hide abstract] ABSTRACT: The flagellated protozoan Giardia duodenalis is a worldwide parasite causing giardiasis, an acute and chronic diarrheal disease. Metabolism in G. duodenalis has a limited complexity thus making metabolic enzymes ideal targets for drug development. However, only few metabolic pathways (i.e, carbohydrates) have been described so far. Recently, the parasite homolog of the mitochondrial-like glycerol-3-phosphate dehydrogenase (gG3PD) has been identified among the interactors of the g14-3-3 protein. G3PD is involved in glycolysis, electron transport, glycerophospholipids metabolism and hyperosmotic stress response, and is emerging as promising target in tumor treatment. In this work, we demonstrate that gG3PD is a functional flavoenzyme able to convert glycerol-3-phosphate into dihydroxyacetone phosphate and that its activity and the intracellular glycerol level increase during encystation. Taking advantage of co-immunoprecipitation assays and deletion mutants, we provide evidence that gG3PD and g14-3-3 interact at the trophozoite stage, the intracellular localization of gG3PD is stage dependent and it partially co-localizes with mitosomes during cyst development. Finally, we demonstrate that the gG3PD activity is affected by the antitumoral compound 6-(7-nitro-2,1,3-benzoxadiazol-4-ylthio)hexanol (NBDHEX), that results more effective in vitro at killing G. duodenalis trophozoites than the reference drug metronidazole. Overall, our results highlight the involvement of gG3PD in processes crucial for the parasite survival thus proposing this enzyme as target for novel anti-giardial interventions.
Full-text · Article · Jun 2015 · Frontiers in Microbiology