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E Pozio

Publications and source records attributed to E Pozio.

At least 55 records · Page 3Linked to original sources
PubMed2001

New patterns of Trichinella infection.

Human and animal trichinellosis should be considered as both an emerging and reemerging disease. The reemergence of the domestic cycle has been due to an increased prevalence of Trichinella spiralis, which has been primarily related to a breakdown of government veterinary services and state farms (e.g., in countries of the former USSR, Bulgaria, Romania), economic problems and war (e.g., in countries of the former Yugoslavia), resulting in a sharp increase in the occurrence of this infection in swine herds in the 1990s, with a prevalence of up to 50% in villages in Byelorussia, Croatia, Latvia, Lithuania, Romania, Russia, Serbia, and the Ukraine, among other countries. The prevalence has also increased following an increase in the number of small farms (Argentina, China, Mexico, etc.) and due to the general belief that trichinellosis was a problem only until the 1960s. The sylvatic cycle has been studied in depth at both the epidemiological and biological level, showing the existence of different etiological agents (Trichinella nativa, Trichinella britovi, Trichinella murrelli, Trichinella nelsoni) in different regions and the existence of "new" transmission patterns. Furthermore, the role of game animals as a source of infection for humans has greatly increased both in developed and developing countries (Bulgaria, Canada, Lithuania, some EU countries, Russia, USA, etc.). The new emerging patterns are related to non-encapsulated species of Trichinella (Trichinella pseudospiralis, Trichinella papuae, Trichinella sp.), infecting a wide spectrum of hosts (humans, mammals including marsupials, birds and crocodiles) and to encapsulated species (T. spiralis, T. britovi, and T. murrelli) infecting herbivores (mainly horses). The existence of non-encapsulated species infecting mammals, birds and crocodiles had probably remained unknown because of the difficulties in detecting larvae in muscle tissues and for the lack of knowledge on the role of birds and crocodiles as a reservoir of Trichinella. On the other hand, it is not known whether horse and crocodile infections existed in the past, and their occurrence has been related to improper human behavior in breeding. The problem of horse-meat trichinellosis is restricted to France and Italy, the only two countries where horse-meat is eaten raw, whereas mutton and beef have been found to be infected with Trichinella sp. only in China.

Alligators and Crocodiles↗
PubMed2001

Genotyping Cryptosporidium parvum by single-strand conformation polymorphism analysis of ribosomal and heat shock gene regions.

Polymerase chain reaction (PCR)-coupled single-strand conformation polymorphism (SSCP) approaches utilizing nuclear DNA regions of the small subunit (SSU) of ribosomal RNA and heat shock protein 70 gene (HSP70) were established for genotyping Cryptosporidium parvum. The regions were amplified (individually or in a multiplex reaction) by PCR from DNA extracted from oocysts from ruminant or human hosts, then denatured and subjected to electrophoresis in a mutation detection enhancement (nondenaturing) gel matrix. Single-strand profiles produced in SSCP allowed the unequivocal identification/differentiation of the two common (human, 1 and cattle, 2) genotypes of C. parvum and the direct display of sequence variability within some samples, reflecting population variation. As these are considered among the most closely related genotypes (based on SSU and HSP70 sequence data), these findings and other preliminary results for C. felis (from cat) C. serpentis (from snake) and C. baileyi (from bird) indicate that the SSCP approaches established could be employed to identify any of the currently recognised genotypes and species of Cryptosporidium.

Animals↗
PubMed2001

Trichinella pseudospiralis populations of the Palearctic region and their relationship with populations of the Nearctic and Australian regions.

Since few non-encapsulated isolates of Trichinella have been studied to date, their level of differentiation from encapsulated species and the taxonomic value of the observed polymorphisms remain to be determined. To this end, biological, biochemical and molecular data from 11 isolates of Trichinella pseudospiralis and one isolate of Trichinella papuae were examined using the broad group of encapsulated species and genotypes for comparison. Single-worm cross-breeding experiments and reproductivity capacity indices revealed F1 progeny only among T. pseudospiralis isolates from different zoogeographical regions, whereas no F1 were produced when T. pseudospiralis was crossed with T. papuae. Furthermore, unlike T. pseudospiralis, T. papuae failed to infect chickens. Comparative analysis of 12 allozymes revealed a single difference between Nearctic and Australian isolates of T. pseudospiralis, but substantial differences when compared with T. papuae (i.e. two unique and six diagnostic markers). Molecular studies involving mitochondrial-derived genes encoding cytochrome oxidase I and the large subunit ribosomal DNA indicated a high level of sequence similarity among T. pseudospiralis isolates; however, a concomitantly high level of variation was observed in expansion segment five of the genomic large subunit ribosomal DNAs among T. pseudospiralis isolates and between this species and T. papuae. Collectively, these results demonstrate high uniformity among isolates of T. pseudospiralis from Eurasia and polymorphism among isolates of T. pseudospiralis belonging to different zoogeographical regions; the results corroborate the classification of T. papuae as a differentiated species.

Animals↗
PubMed2001

Large sequence variation at two microsatellite loci among zoonotic (genotype C) isolates of Cryptosporidium parvum.

The genetic polymorphism among 57 Cryptosporidium parvum isolates belonging to genotype 'C' was studied by PCR amplification and the sequencing of two microsatellite loci (ML1 and ML2). A comparative analysis of DNA sequences showed the presence of three (ML1-238, ML1-226, and ML1-220) and seven (ML2-231, ML2-229, ML2-227, ML2-213, ML2-193, ML2-191, and ML2-187) different alleles at these two loci. Alleles differed by expansions/contractions of the microsatellite repeats that generated length polymorphisms. Some alleles were found to be associated with infections of all examined hosts (calf, kid, lamb, and human), whereas others were either associated with a single host, or were geographically restricted. When considering the information from both loci, some preferential associations between alleles are apparent. These data confirm the utility of microsatellite markers for the molecular identification of C. parvum, which is of particular relevance in the investigation of the source of infection of outbreaks and single cases, as well as for genetic studies.

Animals↗
PubMed2001

First report of Trichinella nativa in red foxes (Vulpes vulpes schrencki) from Otaru City, Hokkaido, Japan.

Forty-three red foxes (Vulpes vulpes schrencki) and nine raccoon dogs (Nyctereutes procyonoides viverrinus) were captured in Otaru City, Hokkaido, Japan and examined by muscle digestion for the presence of Trichinella sp. larvae. Of the foxes, five (11.6%) were positive for larvae of Trichinella nativa while none of the raccoon dogs were found to be positive. This finding suggests that the red foxes are important reservoir hosts of sylvatic trichinellosis in Otaru, Hokkaido. This is the first report on Trichinella nativa in wild red foxes of Hokkaido, Japan.

Animals↗
PubMed2001

The detection of encapsulated and non-encapsulated species of Trichinella suggests the existence of two evolutive lines in the genus.

In recent years, the discovery of many non-encapsulated isolates of Trichinella, designated Trichinella pseudospiralis and the identification of a new non-encapsulated species, Trichinella papuae, has revealed that the biomass of the genus Trichinella does not only include the well known encapsulated species (T. spiralis, T. nativa, T. britovi, T. murrelli, and T. nelsoni) but also includes geographically disseminated, non-encapsulated species that represent important biological entities in the genus. Larvae of the first stage (L1) of both non-encapsulated and encapsulated species are able to penetrate the muscle cell and induce a dedifferentiation of this cell. But following this point in the parenteral cycle, non-encapsulated and encapsulated species diverge with respect to their developmental strategies where L1 of encapsulated species are able to induce the nurse cell to synthesize collagen, unlike non-encapsulated larvae which do not induce collagen production. The presence or absence of a collagen capsule is of great importance in the natural cycle of these parasites in that it allows the encapsulated larva to survive to substantially longer periods of time and therefore remain infective even within putrified muscle tissue.

Animals↗
PubMed2001

Evaluation of two PCR-based techniques for molecular epidemiology in Finland, a high-endemic area with four sympatric Trichinella species.

Trichinella larvae collected from wildlife, domestic and synanthropic animals in Finland were identified to species by two molecular techniques: Random amplified polymorphic DNA (RAPD) polymerase chain reaction (PCR) and the recently described multiplex PCR. The RAPD-PCR was very sensitive to the sub-optimal preservation muscle larvae and resulting in weak and smeared bands on the gels for such material. However, the same samples yielded easily recognizable bands in the multiplex PCR; this latter technique is then recommended for epidemiological studies, especially when the preservation of the samples is sub-optimal. For larvae in good condition the unequivocal bands obtained by multiplex was the easiest identifiable. Four species of Trichinella were identified in the material: T. spiralis, T. nativa, T. britovi, and T. pseudospiralis. Trichinella britovi is a new record for Finland, and T. pseudospiralis is a new record for Northern Europe. Mixed infections between T. britovi and T. spiralis, T. nativa and T. spiralis, and between T. britovi and T. nativa were detected; this is the first record of a mixed infection between T. spiralis and T. nativa in a naturally infected host. Raccoon dogs were the only host species from which all of the four Trichinella species were detected. Trichinella spiralis was found in both domestic animals and wildlife, but none of the sylvatic Trichinella species were detected in domestic pig.

Animals↗
PubMed2001

Twelve years of activity of the International Trichinella Reference Centre.

The ITRC is the official reference laboratory of both the International Commission on Trichinellosis (since 1988) and the International Office of Epizootics (since 1992). The ITRC was created as a repository for Trichinella strains and as a source of materials and information for international research in 1988. To date, about 900 isolates of human and animal origin from throughout the world have been examined and identified by new procedures developed at the ITRC or in collaboration with other institutions. Using material from this collection, the ITRC has provided a complete revision of the systematics of the genus Trichinella. The ITRC database can be consulted by accessing the web-site: www.simi.iss.it/trichinella/index.htm.

Animals↗
PubMed2001

Ultrastructural characteristics of nurse cell-larva complex of four species of Trichinella in several hosts.

The nurse cell-larva complex of nematodes of the genus Trichinella plays an important role in the survival of the larva in decaying muscles, frequently favouring the transmission of the parasite in extreme environmental conditions. The ultrastructure of the nurse cell-larva complex in muscles from different hosts infected with T. nativa (a walrus and a polar bear), T. spiralis (horses and humans), T. pseudospiralis (a laboratory mouse) and T. papuae (a laboratory mouse) were examined. Analysis with transmission electron microscope showed that the typical nurse cell structure was present in all examined samples, irrespective of the species of larva, of the presence of a collagen capsule, of the age of infection and of the host species, suggesting that there exists a molecular mechanism that in the first stage of larva invasion is similar for encapsulated and non-encapsulated species.

Animals↗
PubMed2001

Sylvatic trichinellosis in Texas.

There are no published reports of domestic or sylvatic trichinellosis in Texas. The aim of the present survey was to determine the presence of Trichinella species in selected representative species of potential wildlife reservoirs in southern Texas. In 1998-99, tongues of 211 wild mammals were collected in southern Texas: 154 coyotes (Canis latrans), three bobcats (Lynx rufus), 32 racoons (Procyon lotor), 13 opossum (Didelphis marsupialis), four ocelots (Leopardus pardalis) and five wild boars (Sus scrofa). Presence of Trichinella sp. larvae was investigated by artificial digestion and larvae of positive samples were identified at the species level by a multiple-polymerase chain reaction analysis. Nine (5.8%) coyotes had trichinellosis; in the muscles of seven of these coyotes, the larvae were identified as Trichinella murrelli. This is the first report of sylvatic trichinellosis in Texas.

Animals↗
PubMed2001

Epidemiological studies on animal and human trichinellosis in Estonia.

From 1992 to 1999, muscle samples from 814 sylvatic animals and 1,173 domestic and synanthropic animals were collected in 15 districts of Estonia; the prevalence of trichinellosis ranged from 1.0% to 79.4% for sylvatic animals and from 0.6% to 24.5% for domestic or synanthropic animals and for animals from fur-bearing farms. The most important reservoirs of Trichinella in nature were the raccoon dog, the red fox, the lynx and the wolf. Three species of Trichinella (T. spiralis, T. nativa, and T. britovi) were identified by several types of PCR-based analyses. Meat from sylvatic animals was the main source of Trichinella infection for humans.

Animals↗
PubMed2001

High prevalence of Trichinella nativa infection in wolf (Canis lupus) populations of Tvier and Smoliensk regions of European Russia.

Domestic and sylvatic trichinellosis have frequently been documented in European regions of Russia, with the highest prevalence reported in wolves (Canis lupus). From 1998 to 2000, 75 carcasses of wolves shot by hunters were tested for Trichinella larvae, and 73 (97.3%) of them were found to be positive. This very high prevalence of infection, the highest ever detected in a natural population of carnivores, could be explained by the human impact on the natural ecosystem. In fact, the diet of wolves living in the region under study mainly consists of carcasses of dogs and wolves, which are left in the forest or used as bait by hunters.

Animals↗
PubMed2001

Epidemiology of swine trichinellosis in the Republic of Croatia.

In order to study the epidemiology of trichinellosis with special emphasis on swine a detailed study was performed. The goals of the study were to define the prevalence of trichinellosis in swine and rats and to determine the etiological agents of the disease with special emphasis on sylvatic species, Trichinella britovi. Considering the obtained data it can be concluded that the risk of Trichinella infection for swine in endemic areas in Croatia is rather high today. On the contrary, a sharp decline in human cases is registered what is certainly a result of obligatory trichinelloscopy even for private purposes. The parasite was found to be prevalent in rats too. Studies on genotypes suggest that Trichinella spiralis is the most prevalent etiological agent of domestic trichinellosis in Croatia, even so the sylvatic species Trichinella britovi can be also present in the domestic habitat suggesting a link between the sylvatic and domestic cycle.

Animals↗
PubMed2001

Diagnosis and epidemiology of Trichinella infections in wildlife in The Netherlands.

Trichinella infections in foxes and wild boars were studied to determine the prevalence of infection in wildlife in the Netherlands. Muscles of 429 forelegs of foxes (Vulpes vulpes) and diaphragms of 11 wild boars (Sus scrofa) were artificially digested. Single larvae of Trichinella were identified at species level using random amplified polymorphic DNA (RAPD-PCR). In addition, an ELISA using ES antigen was used to test serum samples of 458 wild boars. The prevalence of Trichinella in foxes ranged from 3.9% in the the eastern part of the country, 13.1% in the central part of the country and 1.3% in the most western part of the country. Trichinella larvae of foxes were identified as T. britovi. In most samples, identification of larvae did not show reproducible results. The serological prevalence of Trichinella infections in wild boars was 6.8%. Wild boar populations are located in the central and in the southern part of the country. Trichinella larvae of wild boar were identified as T. spiralis. These results show that two Trichinella species are involved in the epidemiology of trichinellosis among wildlife. On the basis of previous reports, the present results suggest that the prevalence of Trichinella infection in wildlife is increasing in the last 20 years.

Animals↗
PubMed2001

Epidemiology of human and animal trichinellosis in Italy since its discovery in 1887.

The epidemiology of trichinellosis in Italy is characterised by a sylvatic cycle present only on the mainland. The domestic cycle probably never existed, though a domestic focus occurred on the island of Sicily between 1933 and 1946. The red fox is the main reservoir, with the prevalence of infection ranging from 0.0% in lowlands to 60% in the Alps. The main etiological agent is Trichinella britovi. Trichinella pseudospiralis has been detected in two birds. From 1948 to March 2000, trichinellosis was diagnosed in 1,347 persons, who acquired the infection in 21 outbreaks.

Animals↗
PubMed2001

An expected outbreak of human trichinellosis for the consumption of horsemeat.

In late February 1998, an outbreak of human trichinellosis occurred in the town of Piacenza (northern Italy) among 92 persons who had eaten raw horsemeat. The source of infection was a horse imported to the abattoir of Brescia one month previously. Although the horse had been found to be positive for trichinellosis upon routine examination, the head of an uninfected horse was exchanged with the head of the infected animal, which was mistakenly placed on the market.

Animals↗