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Research in Veterinary Science May 2021Apicomplexan species in the genus Sarcocystis form tissue cysts, in their intermediate hosts, similar to those established in chronic toxoplasmosis. More than 200... (Review)
Review
Apicomplexan species in the genus Sarcocystis form tissue cysts, in their intermediate hosts, similar to those established in chronic toxoplasmosis. More than 200 species are known, but just a few are known to threaten human health owing to infection in livestock species. Intestinal sarcocystosis occurs when people consume raw or undercooked beef contaminated with Sarcocystis hominis or S. heydorni or undercooked pork contaminated with S. suihominis. Those infections may cause mild enteritis, but most infections are thought to be asymptomatic. People also become dead-end (intermediate) hosts for non-human Sarcocystis spp. after accidentally ingesting sporocysts, leading to extraintestinal sarcocystosis. The clinical spectrum may range from asymptomatic muscle cysts to a severe, acute, eosinophilic myositis associated with systemic symptoms with peripheral eosinophilia. Most human cases have been described from Southeast Asia, but Sarcocystis parasites have a worldwide distribution, especially where livestock is raised, and human infections in other areas have been described but may be underrecognized.
Topics: Animals; Cattle; Cattle Diseases; Humans; Prevalence; Red Meat; Sarcocystis; Sarcocystosis; Zoonoses
PubMed: 33626441
DOI: 10.1016/j.rvsc.2021.02.008 -
Veterinary Parasitology Sep 2015Sarcocystis species are worldwide spread cyst-forming protozoa that can infect wild boar but little is known about the prevalence of these parasites. In this study we...
Sarcocystis species are worldwide spread cyst-forming protozoa that can infect wild boar but little is known about the prevalence of these parasites. In this study we assessed the prevalence of Sarcocystis spp. infections in wild boars from northeastern Portugal, for which novel PCR testing assays targeting Sarcocystis genus, S. miescheriana and S. suihominis were implemented, and risk factors potentially associated with these infections were evaluated. Samples from muscle tissue, namely diaphragm (n=102), oesophagus (n=96) and heart (n=101), were collected from a total of 103 wild boar hunted between October 2011 and February 2012. Diaphragm muscle was used for the PCR detection of Sarcocystis nucleic acids since a higher proportion of samples showed the presence of cysts during histological examination. PCR assay targeting Sarcocystis genus yielded a 73.8% infection rate, which indicate a high level of exposure to these protozoan parasites among wild boars. These samples showed to be positive with the S. miescheriana-specific PCR assay and no sample was positive with the S. suihominis-specific assay, suggesting that a single species infecting wild boar is circulating in Portugal. These results were confirmed by the partial sequencing of the 18S rRNA gene amplified from selected samples from different geographic regions. Adults, young adults and female wild boars were found to be more likely infected. Hunters have an important role in the life cycle of S. miescheriana since potentially infected viscera and carcasses can be left behind promoting the protozoan dissemination to the scavenging final hosts. If hunting dogs bite and ingest infected meat they can perpetuate the life cycle of Sarcocystis spp. spreading oocysts or sporocysts in the environment.
Topics: Aging; Animals; DNA, Protozoan; Female; Male; Muscle, Skeletal; Odds Ratio; Polymerase Chain Reaction; Portugal; RNA, Ribosomal, 18S; Risk Factors; Sarcocystis; Sarcocystosis; Species Specificity; Sus scrofa; Swine; Swine Diseases
PubMed: 26319199
DOI: 10.1016/j.vetpar.2015.08.015 -
Parasitology Research Apr 2019A sample of the diaphragm was collected from each of 100 wild boars legally hunted in the Val Grande National Park in north-western Italy and examined for the presence...
A sample of the diaphragm was collected from each of 100 wild boars legally hunted in the Val Grande National Park in north-western Italy and examined for the presence of Sarcocystis infection by histological and molecular methods. In histological sections, thick-walled sarcocysts consistent with those of Sarcocystis miescheriana were detected in 32 wild boars. Genomic DNA extracted from diaphragm samples was initially subjected to PCR amplification of the internal transcribed spacer 1 (ITS1) region, and 97 wild boars were found to harbour a Sarcocystis infection at this screening. Selected DNA samples were then subjected to PCR amplification and sequencing of the ITS1 region and the 18S and 28S ribosomal RNA (rRNA) genes of the nuclear ribosomal DNA unit, while all positive samples were subjected to PCR amplification of the mitochondrial cytochrome c oxidase subunit I (cox1) gene. S. miescheriana was identified in 97 wild boars (97%), while the zoonotic Sarcocystis suihominis was identified in one wild boar (1%), which also harboured S. miescheriana. Intra-specific sequence variation was found in all four DNA regions of S. miescheriana examined and in the 18S rRNA gene and ITS1 region of S. suihominis. The partial cox1 gene was amplified and sequenced from 72 isolates of S. miescheriana, yielding 43 haplotypes with pairwise sequence identities of 97.6-99.9%. These haplotypes were 79.1-79.8% identical with the cox1 sequence of S. suihominis. Phylogeny based on cox1 sequences placed S. miescheriana and S. suihominis as sister species within a clade comprising mainly Sarcocystis spp. of ruminants with felids as known or presumed definitive hosts. The same was true for the phylogeny based on 18S rRNA gene sequences.
Topics: Animals; Cyclooxygenase 1; DNA, Intergenic; DNA, Ribosomal; Diaphragm; Female; Italy; Male; Molecular Typing; Phylogeny; Polymerase Chain Reaction; Prevalence; RNA, Ribosomal, 18S; RNA, Ribosomal, 28S; Sarcocystis; Sarcocystosis; Sequence Analysis, DNA; Sus scrofa; Swine
PubMed: 30788573
DOI: 10.1007/s00436-019-06249-2 -
Parasitology Research Oct 2020A total of 57 tissue samples of domestic pigs (Sus scrofa) were collected from the meat outlets of five north Indian states and examined for sarcocystosis by...
A total of 57 tissue samples of domestic pigs (Sus scrofa) were collected from the meat outlets of five north Indian states and examined for sarcocystosis by histological and molecular methods. The genomic DNA extracted from five representative positive isolates was subjected to PCR amplification of the partial 18S rRNA gene followed by cloning and sequencing. Sequence analysis of the newly generated Indian isolates recorded 96.9-100.0% identity with published sequences of Sarcocystis suihominis. Two new haplotypes that have not been previously described manifested 99.5-100.0% nucleotide homology within themselves. In the phylogenetic analysis, Indian isolates of S. suihominis grouped together with S. suihominis originating from Italy, and they collectively formed a sister clade with Sarcocystis miescheriana within a clade containing various Sarcocystis spp. of ruminants having felids as final hosts. At the same time, this clade separated from a sister clade containing Sarcocystis spp. of bovid or cervid ruminants using canids as known or surmised definitive host. The current study established the phylogenetic relationship of Indian isolates of S. suihominis with various Sarcocystis spp. as well as with other taxa of Sarcocystidae family based on 18S rRNA gene for the first time.
Topics: Animals; Haplotypes; India; Phylogeny; RNA, Ribosomal, 18S; Sarcocystis; Sarcocystosis; Sus scrofa; Swine; Swine Diseases
PubMed: 32833051
DOI: 10.1007/s00436-020-06857-3 -
Research in Veterinary Science Nov 2023The increase of wild boar populations density and their meat consumption across Europe could expose humans to a plethora of foodborne diseases as sarcocystosis, caused...
The increase of wild boar populations density and their meat consumption across Europe could expose humans to a plethora of foodborne diseases as sarcocystosis, caused by the zoonotic protozoan Sarcocystis suihominis. Humans become infected by eating raw or undercooked pig (Sus scrofa domesticus) containing S. suihominis sarcocysts. Despite this, to date very few data are available on the risk of infection by this parasite to wild boar (Sus scrofa) meat consumers. Thus, the present study aimed to assess the occurrence of Sarcocystis spp. in wild boars from southern Italy, applying both histology and a new multiplex PCR assay targeting the cox1 gene. Between 2019 and 2020, 997 muscle tissues (i.e., n = 269 oesophagus, n = 277 diaphragms, n = 298 hearts, n = 153 tongues) from 311 wild boars were collected and screened by a combined histological and molecular approach. Overall, 251 (80.7%) animals tested were positive for Sarcocystis spp., and S. miescheriana whose definitive hosts are canids, was the only molecularly identified species. A statistically significant difference (p < 0.05) in the prevalence of Sarcocystis infection was found according to the wild boar age and muscle tissue. Findings outlined the low zoonotic potential of infection to humans via wild boar meat consumption in Italy and the importance of the application of new molecular methods in distinguishing different Sarcocystis species.
Topics: Animals; DNA, Mitochondrial; Italy; Multiplex Polymerase Chain Reaction; Phylogeny; Sarcocystis; Sarcocystosis; Sus scrofa; Swine; Swine Diseases; Electron Transport Complex IV
PubMed: 37812987
DOI: 10.1016/j.rvsc.2023.105039 -
Clinical Microbiology Reviews Apr 2015Recurrent outbreaks of muscular sarcocystosis among tourists visiting islands in Malaysia have focused international attention on sarcocystosis, a disease once... (Review)
Review
Recurrent outbreaks of muscular sarcocystosis among tourists visiting islands in Malaysia have focused international attention on sarcocystosis, a disease once considered rare in humans. Sarcocystis species require two hosts, definitive and intermediate, to complete their life cycle. Humans can serve as definitive hosts, with intestinal sarcocystosis for two species acquired from eating undercooked meat: Sarcocystis hominis, from beef, and Sarcocystis suihominis, from pork. Symptoms such as nausea, stomachache, and diarrhea vary widely depending on the number of cysts ingested but appear more severe with pork than with beef. Humans serve as intermediate hosts for Sarcocystis nesbitti, a species with a reptilian definitive host, and possibly other unidentified species, acquired by ingesting sporocysts from feces-contaminated food or water and the environment; infections have an early phase of development in vascular endothelium, with illness that is difficult to diagnose; clinical signs include fever, headache, and myalgia. Subsequent development of intramuscular cysts is characterized by myositis. Presumptive diagnosis based on travel history to tropical regions, elevated serum enzyme levels, and eosinophilia is confirmed by finding sarcocysts in muscle biopsy specimens. There is no vaccine or confirmed effective antiparasitic drug for muscular sarcocystosis, but anti-inflammatory drugs may reduce symptoms. Prevention strategies are also discussed.
Topics: Animals; Enzymes; Humans; Intestines; Life Cycle Stages; Meat; Muscles; Sarcocystis; Sarcocystosis; Travel
PubMed: 25715644
DOI: 10.1128/CMR.00113-14 -
Parasitology Research Dec 2019In this study, 36.8% (28/76) of tissue samples collected from domestic pigs (Sus scrofa) contained sarcocysts, as determined by light microscopy. The organisms were...
In this study, 36.8% (28/76) of tissue samples collected from domestic pigs (Sus scrofa) contained sarcocysts, as determined by light microscopy. The organisms were identified as Sarcocystis miescheriana and Sarcocystis suihominis based on their morphological and molecular characteristics. Four genetic markers, i.e., 18S rDNA, 28S rDNA, ITS-1 region (ITS-1), and the mitochondrial COX1 gene (COX1), of the two parasites were sequenced and analyzed, and the 28S rDNA and ITS-1 of S. suihominis obtained from pigs constituted the first records of these markers in GenBank. The sequences of the four loci (18S rDNA, 28S rDNA, ITS-1, and COX1) of S. miescheriana shared high identities with those of S. miescheriana obtained from domestic and/or wild pigs in GenBank, with similarities of 99.6%, 99.6%, 95.9%, and 95.4%, respectively. The 18S rDNA sequences of S. suihominis exhibited 99.4% identity with those of S. suihominis from domestic and wild pigs. The comparison of the newly obtained sequences of the four genetic markers between the two parasites revealed that the interspecific similarities of 18S rDNA, 28S rDNA, ITS-1, and COX1 were 97.7%, 96.6%, 80.3%, and 81.2%, respectively. Therefore, the two species could be better discriminated with ITS-1 and mitochondrial COX1 compared with 18S rDNA or 28S rDNA. The phylogenetic analysis using 28S rDNA indicated that the two Sarcocystis species in domestic pigs had a close relationship.
Topics: Animals; China; DNA, Protozoan; DNA, Ribosomal; Genes, Mitochondrial; Phylogeny; Polymerase Chain Reaction; RNA, Ribosomal, 18S; Sarcocystis; Sarcocystosis; Sus scrofa; Swine; Swine Diseases
PubMed: 31728723
DOI: 10.1007/s00436-019-06521-5 -
Parasitology Research Feb 2023Sarcocystis spp. are intracellular protozoan parasites with an obligatory heteroxenous life cycle. The objective of this study is to identify Sarcocystis spp. in wild...
Sarcocystis spp. are intracellular protozoan parasites with an obligatory heteroxenous life cycle. The objective of this study is to identify Sarcocystis spp. in wild boar muscles from Argentina by light and transmission electron microscopy and molecular characterization. Muscle samples from diaphragm, tongue, masseter, intercostals, heart, and forelimbs of 240 wild boars were analyzed. Of the animals, 48.3% (116/240) were positive for sarcocysts by light microscopy, whereas 45.8% (110/240) were positive for Sarcocystis spp. by PCR targeting 18S rRNA fragment. These samples were subjected to a specific PCR for S. suihominis coxI gene, 3.6% (4/110) of which were weak positives. Unfortunately, sequence analysis was inconclusive. This could be related to a potentially low S. suihominis cyst load in the samples, or to an incomplete primer matching with the South American S. suihominis sequences. Seventeen individual sarcocysts were positive by PCR for the 18S rRNA fragment, whose sequences showed 99.75-100% identity with each other and with previously reported S. miescheriana sequences. A total of 21 cysts collected from 11 muscle samples and analyzed by TEM presented a cyst wall type compatible with S. miescheriana, and one cyst presented an ultrastructure compatible with S. suihominis. The latter came from a sample that also contained S. miescheriana cysts, indicating that the animal was co-infected. This is the first study that provides infection rates and describes and identifies morphological and molecular features of Sarcocystis spp. cysts in wild boars from South America.
Topics: Animals; Swine; Sarcocystis; Sarcocystosis; RNA, Ribosomal, 18S; Argentina; Diaphragm; Cysts; Sus scrofa; Phylogeny
PubMed: 36471091
DOI: 10.1007/s00436-022-07743-w -
Parasitology Research Feb 2024Sarcocystis are Apicomplexan protozoa with a dixenous life cycle that includes a predator and a prey as definitive and intermediate hosts, respectively. Domestic and...
Sarcocystis are Apicomplexan protozoa with a dixenous life cycle that includes a predator and a prey as definitive and intermediate hosts, respectively. Domestic and wild pigs are intermediate hosts of S. suihominis, with formation of sarcocysts in their muscles, while humans and non-human primates act as final hosts. After ingesting raw or undercooked sarcocyst-infested pork, signs of gastroenteritis including inappetence, nausea, vomiting, and diarrhea may develop in humans. Moreover, excretion of infective forms with human feces leads to dissemination of the parasite in the environment. In this study, macroscopic sarcocysts of white color, oval shape, and a diameter of approximately 3-8 mm were found in the skeletal muscle of a slaughtered domestic pig (Sus scrofa domesticus) destined for human consumption in an abattoir of Makurdi, Benue State, Nigeria. Sarcocyst DNA was used as template to PCR amplify the near-complete length of the 18S rRNA gene and a fragment of the cytochrome c oxidase subunit 1 (cox-1) gene. Amplicons were sequenced and used to construct phylogenetic trees with selected available Sarcocystis spp. sequences. In both cases, the placement of the analyzed sequences with S. suihominis was strongly supported, confirming the species identity of this macroscopic sarcocyst-forming parasite. This constitutes the first molecular identification of S. suihominis in Nigeria and the African continent. Proximity between pigs and humans, and poor sanitary conditions frequently encountered in pig farms of Nigeria might favor the dissemination of this zoonotic parasite, posing a threat to public health.
Topics: Animals; Humans; Swine; Sarcocystis; Sarcocystosis; Phylogeny; Nigeria; RNA, Ribosomal, 18S; Muscle, Skeletal; Sus scrofa
PubMed: 38393400
DOI: 10.1007/s00436-024-08160-x -
The Journal of Veterinary Medical... Mar 1998Sarcoystis suihominis was detected for the first time in Japan from the heart and diaphragm of 5 out 600 older culled breeding pigs slaughtered in Saitama Prefecture,...
Sarcoystis suihominis was detected for the first time in Japan from the heart and diaphragm of 5 out 600 older culled breeding pigs slaughtered in Saitama Prefecture, Japan. Fresh cysts were 1,080-2,040 x 106-170 microns in size. Bradysoites measured 15 x 4 microns on average. The cyst wall was usually observed thick, 4-6 microns, and striated, but occasionally thin and smooth according to the difference in sectioning angle and in portion of cysts. Scanning electron microscopy showed that many palisade-like villar protrusions, 6-6 x 0.3-0.5 microns in size, were closely folded onto the surface of cyst. A small number of microtubules were seen in the core of protrusion. No dogs nor domestic cats fed with 20 fresh cysts each excreted oocysts or sporocysts in the feces throughout the experimental period of 30 days.
Topics: Animals; Cats; Diaphragm; Dogs; Heart; Japan; Myocardium; Sarcocystis; Sarcocystosis; Swine; Swine Diseases
PubMed: 9560777
DOI: 10.1292/jvms.60.307