Molecular identification of Sarcocystis species in diaphragm muscle tissue of European mouflon (Ovis gmelini musimon) from Austria

Previous morphological studies suggested that mouflon may have sarcocysts similar to those of sheep. However, to date, no molecular-based studies of the species of Sarcocystis infecting mouflon have been done. The present study identified Sarcocystis species in diaphragm muscle samples from 20 European mouflon (Ovis gmelini musimon). Molecular identification using the cox1 sequence analysis was performed on sarcocysts excised from muscle tissue and on DNA from digested muscle samples. Both frequency and intensity of infection in mouflon were high with 19 of 20 animals testing Sarcocystis positive and > 50 cysts per gram of tissue recovered from 10 of the 19 Sarcocystis positive animals. Molecular analysis revealed dominant Sarcocystis tenella (18/19 animals) and Sarcocystis arieticanis (1/19 animals), whose known intermediate hosts are sheep. In addition, Sarcocystis capracanis, which is known to form sarcocysts in goats, was detected in two animals. The results of this study demonstrated the digestion method to be superior over the direct isolation of sarcocysts for the molecular identification of Sarcocystis species in a certain host. Future research of Sarcocystis diversity in wild ovine and caprine species is needed.

Sarcocystis species in bovine carcasses from a Belgian abattoir: a cross-sectional study

BACKGROUND

Sarcocystis species are obligatorily heteroxenous parasites, of which some are zoonotic, representing a public health and economic impact. This study investigated the occurrence of Sarcocystis spp. in cattle sampled from a Belgian slaughterhouse.

METHODS

A total of 200 carcasses were included in the study, sampled during 10 sampling days. The sedimentation method was applied to isolate the sarcocysts from both heart and diaphragm muscles collected from each carcass. Multiplex PCR, PCR-RFLP as well as cox1 gene sequencing techniques were applied serially on collected sarcocysts for species identification.

RESULTS

Sarcocystis spp. were detected in 64% (128/200; 95% CI 57-71%) of the sampled carcasses. Female dairy cattle presented the highest Sarcocystis occurrence rate (91%) as well as the highest Sarcocystis species diversity compared to female beef and male beef. Sarcocystis spp. were detected more often in the heart muscles than in the diaphragm among female beef (p < 0.001) and dairy carcasses (p = 0.001), while in male carcasses no significant difference was observed (p = 0.763). The effect of age was not significant in male carcasses (p = 0.872), while the odds of finding sarcocysts significantly increased with age (p = 0.003) within both types of female carcasses. S. cruzi was the most prevalent species and was found in 56.5% (113/200) of the carcasses, followed by S. hominis (21.0%, 42/200), S. bovifelis (12.5%, 25/200), S. bovini (2.0%, 4/200), S. hirsuta (1.5%, 3/200) and S. heydorni (0.5%, 1/200). Six different species were detected in the diaphragm, while only two species were recovered from the heart. S. cruzi was the most prevalent species in heart, while in the diaphragm, this was S. hominis.

CONCLUSIONS

The detection of S. hominis in 21% of the sampled carcasses presents a potential food safety issue, and further research is warranted into controlling this infection.

Parasites in a hotspot: diversity and specificity patterns of apicomplexans infecting reptiles from the Socotra Archipelago

Although parasites represent a major component of biodiversity, they remain poorly assessed, especially in remote regions. In this study, we screened 461 reptiles from Socotra, the largest and most biologically diverse archipelago in Arabia. Using 18S rRNA primers, we detected various apicomplexan parasites, namely haemogregarines, sarcocystids and eimeriids. Haemogregarines were the most common and genetically diverse, followed by sarcocystids (genus Sarcocystis) and eimeriids (genera Isospora and Lankesterella). All were related to parasites of other reptiles, including species from Arabia, Northern Africa and Asia. Like their 29 endemic reptile hosts, almost all Socotran parasites presented high genetic divergence and ecological differences from those found elsewhere, and probably represent undescribed endemic species. Among hosts, skinks were the most parasitized, which contrasted with similar studies from other areas, probably due to their more generalist diet and habitat use. As expected due to its high species richness, geckos harboured the highest parasite diversity in the archipelago. Parasite diversity also seemed to be correlated to island size, as the largest island harboured most haplotypes. This study emphasizes the importance of screening parasites in wild hosts from remote regions and of considering host ecology to understand disease transmission across taxa.

Genetic characterization and phylogenetic analysis of Sarcocystis suihominis infecting domestic pigs (Sus scrofa) in India

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.

First molecular characterization of Sarcocystis neurona causing meningoencephalitis in a domestic cat in Brazil

Sarcocystis neurona is the main agent associated with equine protozoal myeloencephalitis (EPM). Apart from horses, S. neurona has been occasionally described causing neurologic disease in several other terrestrial animals as well as mortality in marine mammals. Herein, we describe the clinical, pathological, and molecular findings of a fatal case of S. neurona-associated meningoencephalitis in a domestic cat. The causing agent was analyzed by multilocus genotyping, confirming the presence of S. neurona DNA in the tissue samples of the affected animal. Significant molecular differences were found in relation to S. neurona isolates detected in other regions of the Americas. In addition, the parasite was identical to Sarcocystis sp. identified in opossum sporocysts in Brazil at molecular level, which suggests that transmission of. S. neurona in Brazil might involve variants of the parasite different from those found elsewhere in the Americas. Studies including more samples of S. neurona would be required to test this hypothesis, as well as to assess the impact of this diversity.

Morphological and molecular characterizations of Sarcocystis miescheriana and Sarcocystis suihominis in domestic pigs (Sus scrofa) in China

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.

Sarcocystis morae (Apicomplexa) in Fallow Deer (Dama dama) from Spain: Ultrastructure and New Host Record

Members of the genus Sarcocystis are frequently found infecting members of the family Cervidae. Although Sarcocystis species are generally host specific for their intermediate hosts, species in cervids appear to be less host specific. Here, we report fallow deer (Dama dama) as a new host for Sarcocystis morae, originally described from the red deer (Cervus elaphus). Tongues of 69 legally hunted animals in Spain were tested for sarcocysts, and the species were characterized by light microscopy, ultrastructurally and molecularly. Sarcocysts were identified in 66.7% of D. dama. Sarcocysts had thin (<2 μm thick) cyst wall with hair-like villar protrusions bifurcated at their tips resembling type 8a. Genetic sequences obtained for 18S rRNA and COI reached 99.6-100% and 97.9-98.7% similarity, respectively, to those of S. morae from the red deer. The present study provides new data concerning lower level of host specificity within Sarcocystis genus for cervids.

Morphological and molecular description of Sarcocystis ratti n. sp. from the black rat (Rattus rattus) in Latvia

Rodents have been widely studied as intermediate hosts of Sarcocystis; however, only a few reports on these parasites in the black rat (Rattus rattus) are known. Having examined 13 black rats captured in Latvia, sarcocysts were found in skeletal muscles of two mammals and were described as Sarcocystis ratti n. sp. Under a light microscope, sarcocysts were ribbon-shaped, 0.9-1.3 × 0.09-0.14 mm in size and had a thin (0.8-1.3 μm) and smooth cyst wall. The lancet-shaped bradyzoites were 8.3 × 4.3 (7.5-9.3 × 3.9-4.8) μm. Under a transmission electron microscope, the cyst wall was up to 1.3 μm thick, wavy, the ground substance appeared smooth, type 1a-like. Morphologically, sarcocysts of S. ratti were somewhat similar to those of S. cymruensis, S. rodentifelis, and S. dispersa-like previously identified in the brown rat (Rattus norvegicus). On the basis of 18S rDNA, 28S rDNA, and cox1, significant genetic differences (at least 2.3, 4.5, and 5.8%, respectively) were observed when comparing S. ratti with other Sarcocystis species using rodents as intermediate hosts. While ITS1 sequences of S. ratti were highly distinct from other Sarcocystis species available in GenBank. Phylogenetic and ecological data suggest that predatory mammals living near households are definitive hosts of S. ratti.

High prevalence of Sarcocystis calchasi in racing pigeon flocks in Germany

The apicomplexan parasite Sarcocystis calchasi (Coccidia: Eimeriorina: Sarcocystidae) is the causative agent of Pigeon Protozoal Encephalitis (PPE) and infects birds of the orders Columbiformes, Piciformes and Psittaciformes. Accipiter hawks (Aves: Accipitriformes) are the definitive hosts of this parasite. Infections of S. calchasi have been detected in Germany, the United States and Japan. However, the prevalence of the parasite in racing pigeon flocks has not yet been determined. Here, the first cross-sectional prevalence study to investigate S. calchasi in pigeon racing flocks was accomplished including 245 pigeon flocks across Germany. A total of 1,225 muscle biopsies, were taken between 2012 and 2016 and examined by semi-nested PCR for S. calchasi DNA targeting the ITS gene. Additionally, a questionnaire on construction of the aviary as well as management and health status of the flock was conducted. In 27.8% (95% C.I. = 22.3-33.8%) of the flocks, S. calchasi DNA was detected in at least one pigeon. Positive flocks were located in 15 out of 16 federal states. A significant increase of infected racing pigeons was seen in spring. Half-covered or open aviary constructions showed a trend of increase of the prevalence rate, while anti-coccidian treatment and acidified drinking water had no effects. The high prevalence and the geographical distribution of S. calchasi suggest a long-standing occurrence of the parasite in the German racing pigeon population. For pigeons presented with neurological signs or other symptoms possibly related to PPE, S. calchasi should be considered as a potential cause throughout Germany.

Prevalence of Sarcocysts in the Muscles of Raptors from a Rehabilitation Center in North Carolina

The life cycle of Sarcocystis species is heteroxenous (2-host), with carnivores being the definitive host and herbivores serving as intermediate hosts in predator-prey relationships. Raptors (eagles, hawks, falcons, and owls) are apex predators and are not consumed routinely by other carnivores, making the occurrence of sarcocysts in their muscles unusual. Recent reports of sarcocysts in eagles and owls with Sarcocystis encephalitis suggests that this condition may be becoming more frequent, and Sarcocystis falcatula has been implicated as the agent of encephalitis in golden ( Aquila chrysaetos) and bald eagles ( Haliaeetus leucocephalus) as well as great horned owls ( Bubo virginianus). The present study was done to determine the prevalence of sarcocysts of Sarcocystis species in the muscles of raptors from the southeastern United States. Pectoral and heart muscle from 204 raptor patients from the Carolina Raptor Center, Huntersville, North Carolina were tested for the presence of Sarcocystis species using histology. Only a few sarcocysts were seen in sections of pectoral muscle from 39 of 204 raptors (19.1%) and heart muscle from 9 that also had sarcocysts in their pectoral muscle. Two structural types of sarcocysts, thin-walled (1 μm; 62%) or thick-walled (>2 μm, 38%), were seen. Statistical analysis of raptor age and gender was done by Fisher's exact test on samples from raptors with 20 or more samples per group. The prevalence of sarcocysts by age (2 yr or more) was significant for red-shouldered hawks ( Buteo lineatus) ( P = 0.022) and Cooper's hawks ( Accipiter cooperii) ( P = 0.028). Sarcocyst prevalence in male raptors from these groups evaluated statistically were always less than in females. Prevalence in female red-tailed hawks ( Buteo jamaicensis) (42.1%) was significantly greater than in males (6.7%) using Fisher's exact test ( P = 0.047). Examination of case histories from the 39 sarcocyst-positive raptors did not reveal an association with sarcocysts in raptor pectoral or heart muscle and in a diagnosis of encephalitis. Additional studies are needed to determine the epidemiology and relationships of Sarcocystis spp. that use raptors as intermediate hosts and the importance of Sarcocystis spp. in the overall wellbeing of raptors in their natural environments.

Confirmation of Sarcocystis jamaicensis Sarcocysts in IFN-γ Gene Knockout Mice Orally Inoculated with Sporocysts from a Red-Tailed Hawk ( Buteo jamaicensis)

Here, we report confirmation of sarcocysts of Sarcocystis jamaicensis in an experimental intermediate host, IFN-γ gene knockout (KO) mice orally inoculated sporocysts from its natural definitive host, a red-tailed hawk ( Buteo jamaicensis) (RTH). A RTH submitted to the Carolina Raptor Center, Huntersville, North Carolina, was euthanized because it could not be rehabilitated and released. Fully sporulated sporocysts from intestinal scrapings of the RTH were orally fed to 2 laboratory-reared outbred Swiss Webster mice (SW; Mus musculus) and to 2 KO mice. The sporocysts were infective for KO mice but not to SW mice. Both SW mice remained asymptomatic, and neither schizonts nor sarcocysts were found in their tissues when euthanized on day 54 post-inoculation (PI). The KO mice developed neurological signs and were necropsied 38-54 days PI. Schizonts/merozoites were found in both KO mice euthanized and they were confined to the brain. The predominant lesion was meningoencephalitis. Microscopic sarcocysts were found in muscles of both KO mice. When viewed with light microscopy, the sarcocyst wall appeared thin (<1 μm thick) and smooth. Ultrastructural details of sarcocysts are described.

First isolation of Sarcocystis caninum sarcocysts from two domestic dogs (Canis familiaris) from China

The presence of Sarcocystis cysts in the muscle tissue of domestic dogs (Canis familiaris), which normally serve as definitive hosts, is unusual and infrequent. Here, S. caninum sarcocysts were identified for the first time in two of 37 dogs (2.7%) from China. Examination using light microscopy found that the S. caninum sarcocysts were up to 1520 μm long and up to 147 μm wide and contained numerous 1.5-3.3 μm wedge-like villar protrusions (vp). Transmission electron microscopy revealed that the sarcocysts had pleomorphic vp that closely resembled those of "type 9c." Five loci, 18S rDNA, 28S rDNA, mitochondrial cox1, ITS1 and ropB, were sequenced and characterized in S. caninum sarcocysts. The sequences of the five loci shared similarities of 99.9-100%, 99.0-100%, 99.4-100%, 99.6-100%, and 99.7-100%, respectively, with those of S. arctica. Phylogenetic analysis based on the sequences of 28S rDNA and mitochondrial cox1 indicated that S. caninum and S. arctica are closely related to Sarcocystis species that use a raptorial bird as their definitive host.

First molecular characterization and morphological aspects of Sarcocystis fusiformis infecting water buffalo Bubalus bubalis in Egypt

Fresh muscle samples from water buffalo (Bubalus bubalis) aged 2-15, from Giza Province, Egypt; were examined for Sarcocystis infection. Macroscopic ovoid sarcocysts embedded in the muscle tissues of the examined buffaloes were detected; they measured 152-230 (210 ± 7) μm in length and 37-119 (95 ± 3) μm in width. The esophagus was the most infected organ followed by the diaphragm, and tongue, while the heart muscles were the least infected. The cyst cavity was compartmentalized by septa derived from the ground substance located under the primary cyst wall. Using transmission electron microscopy, the primary cyst wall bordered sarcocysts were determined to be 0.08-0.22 μm in thickness, raised from the parasitophorous vacuolar membrane, and surrounded by a secondary cyst wall of host origin. The primary cyst wall had irregular wall folds with numerous cauliflower-like projections of variable sizes and shapes accompanied by knob-like electron-dense elevations. 18S rRNA gene expression studies confirmed that the present parasite isolates belonged to the genus Sarcocystis. The sequence data showed significant identities (>90%) with archived gene sequences from many Eimeriidae organisms, and a dendogram showing the phylogenetic relationship was constructed. The most closely related species was Sarcocystis fusiformis KR186117, with an identity percentage of 98%. The recovered sequences were deposited in the GenBank under the accession number MG572125. The present study, to our knowledge, is the first collective ultrastructural and molecular study that confirmed the taxonomy of sarcocysts isolated from water buffaloes in Egypt as Sarcocystis fusiformis.

Sarcocystosis in South American camelids: The state of play revisited

Members of the genus Sarcocystis (Apicomplexa: Sarcocystidae) are intracellular protozoan parasites that infect a wide range of domestic and wild animals, resulting in economic losses in production animals worldwide. Sarcocystis spp. have indirect life-cycles where canids and felids serve as main definitive hosts while a range of domestic and wild animals serve as intermediate hosts, including South American camelids (SACs) such as alpacas, llamas and guanacos. These animals primarily occur in South American countries on Andean, elevated plains but in recent years, alpacas and llamas have become emerging animal industries in other parts of the world such as Australia, Europe and the USA due to their high-quality fiber, meat and hides. For instance, alpaca meat is becoming popular in many parts of the world due to its lower cholesterol content than other red meat, thereby it has the potential of a valuable product for both local and international markets. However, SAC meat can be degraded and/or even condemned due to the presence of macroscopic sarcocysts in skeletal muscles, leading to significant economic losses to farmers. The infection is generally asymptomatic, though highly pathogenic or even fatal Sarcocystis infections have also been reported in alpacas and llamas. Despite the economic importance of sarcocystosis in SACs, little is known about the life-cycle of parasites involved, disease transmission, epidemiology, pathogenesis, diagnosis, control and public health significance. This review article provides an in-depth analysis of the existing knowledge on the taxonomy, epidemiology, clinicopathology and diagnosis of Sarcocystis in SACs, highlights knowledge gaps and proposes future areas of research that could contribute to our better understanding of sarcocystosis in these animals.

Sarcocystis cymruensis: discovery in Western Hemisphere in the Brown rat (Rattus norvegicus) from Grenada, West Indies: redescription, molecular characterization, and transmission to IFN-γ gene knockout mice via sporocysts from experimentally infected domestic cat (Felis catus)

Rodents are intermediate hosts for many species of Sarcocystis. Little is known of Sarcocystis cymruensis that uses the Brown rat (Rattus norvegicus) as intermediate hosts and the domestic cat (Felis catus) as experimental definitive host. Here, we identified and described Sarcocystis cymruensis in naturally infected R. norvegicus from Grenada, West Indies. Rats (n = 167) were trapped in various locations in two parishes (St. George and St. David). Microscopic, thin (< 1 μm) walled, slender sarcocysts were found in 11 of 156 (7.0%) rats skeletal muscles by squash examination. A laboratory-raised cat fed naturally infected rat tissues excreted sporocysts that were infectious for interferon gamma gene knockout (KO) mice, but not to Swiss Webster outbred albino mice. All inoculated mice remained asymptomatic, and microscopic S. cymruensis-like sarcocysts were found in the muscles of KO mice euthanized on day 70, 116, and 189 post inoculation (p.i.). Sarcocysts from infected KO mice were infective for cats at day 116 but not at 70 days p.i. By transmission electron microscopy, the sarcocyst wall was "type 1a." Detailed morphological description of the cyst wall, metrocytes, and bradyzoites is given for the first time. Additionally, molecular data on S. cymruensis are presented also for the first time. Molecular characterization of sarcocysts 18S rDNA and 28S rDNA, ITS-1, and cox1 loci showed the highest similarity with S. rodentifelis and S. muris. In conclusion, the present study described the natural infection of S. cymruensis in Brown rat for the first time in a Caribbean country and provided its molecular characteristics.

Molecular identification of Sarcocystis lutrae in the European otter (Lutra lutra) and the European badger (Meles meles) from the Czech Republic

Muscular sarcosporidial infections by Sarcocystis lutrae (Apicomplexa: Sarcocystidae) from the otter (Lutra lutra) and badger (Meles meles) (Carnivora: Mustelidae) were found in the Czech Republic. As part of a diversity evaluation of Sarcocystis in wild carnivores during 2016-2017, samples of diaphragm, tongue and hind-limb muscles were collected from nine districts, examined by compression and characterized molecularly. Cyst walls were thin, with no visible protrusions, and histological sections of infected muscle tissue showed no host responses. Fourteen of 17 badgers (82% prevalence) and one otter (100% prevalence) were positive for sarcocysts. Sequence analyses at four loci (18S rRNA, 28S rRNA, ITS1 and cox1) confirmed the identity as S. lutrae. This is also the first report of a co-infection with muscular sarcocystosis and Trichinella in badger. The finding of Trichinella is important from the zoonotic point of view, since badgers are used for meat consumption. Similar and future monitoring of both parasitic taxa are needed.

Examination of Sarcocystis spp. of giant snakes from Australia and Southeast Asia confirms presence of a known pathogen - Sarcocystis nesbitti

We examined Sarcocystis spp. in giant snakes from the Indo-Australian Archipelago and Australia using a combination of morphological (size of sporocyst) and molecular analyses. We amplified by PCR nuclear 18S rDNA from single sporocysts in order to detect mixed infections and unequivocally assign the retrieved sequences to the corresponding parasite stage. Sarcocystis infection was generally high across the study area, with 78 (68%) of 115 examined pythons being infected by one or more Sarcocystis spp. Among 18 randomly chosen, sporocyst-positive samples (11 from Southeast Asia, 7 from Northern Australia) the only Sarcocystis species detected in Southeast Asian snakes was S. singaporensis (in reticulated pythons), which was absent from all Australian samples. We distinguished three different Sarcocystis spp. in the Australian sample set; two were excreted by scrub pythons and one by the spotted python. The sequence of the latter is an undescribed species phylogenetically related to S. lacertae. Of the two Sarcocystis species found in scrub pythons, one showed an 18S rRNA gene sequence similar to S. zamani, which is described from Australia for the first time. The second sequence was identical/similar to that of S. nesbitti, a known human pathogen that was held responsible for outbreaks of disease among tourists in Malaysia. The potential presence of S. nesbitti in Australia challenges the current hypothesis of a snake-primate life cycle, and would have implications for human health in the region. Further molecular and biological characterizations are required to confirm species identity and determine whether or not the Australian isolate has the same zoonotic potential as its Malaysian counterpart. Finally, the absence of S. nesbitti in samples from reticulated pythons (which were reported to be definitive hosts), coupled with our phylogenetic analyses, suggest that alternative snake hosts may be responsible for transmitting this parasite in Malaysia.

Sarcocystis neurona and Neospora caninum in Brazilian opossums (Didelphis spp.): Molecular investigation and in vitro isolation of Sarcocystis spp

Sarcocystis neurona and Neospora spp. are protozoan parasites that induce neurological diseases in horses and other animal species. Opossums (Didelphis albiventris and Didelphis virginiana) are definitive hosts of S. neurona, which is the major cause of equine protozoal myeloencephalitis (EPM). Neospora caninum causes abortion in cattle and infects a wide range of animal species, while N. hughesi is known to induce neurologic disease in equids. The aims of this study were to investigate S. neurona and N. caninum in tissues from opossums in the northeastern Brazil, and to isolate Brazilian strains of Sarcocystis spp. from wild opossums for comparison with previously isolated strains. Carcasses of 39 opossums from Bahia state were available for molecular identification of Sarcocystis spp. and N. caninum in their tissues, and for sporocyst detection by intestinal scraping. In addition, Sarcocystis-like sporocysts from nine additional opossums, obtained in São Paulo state, were tested. Sarcocystis DNA was found in 16 (41%) of the 39 opossums' carcasses; N. caninum DNA was detected in tissues from three opossums. The sporocysts from the nine additional opossums from São Paulo state were tested by bioassay and induced infection in nine budgerigars, but in none of the gamma-interferon knockout mice. In vitro isolation was successful using tissues from all nine budgerigars. The isolated strains were maintained in CV-1 and Vero cells. Three of nine isolates presented contamination in cell culture and were discarded. Analysis of six isolates based on five loci showed that these parasites were genetically different from each other and also distinct from S. neurona, S. falcatula, S. lindsayi, and S. speeri. In conclusion, opossums in the studied regions were infected with N. caninum and Sarcocystis spp. and represent a potential source of infection to other animals. This is the first report of N. caninum infection in tissues from black-eared opossum (D. aurita or D. marsupialis) and white-eared opossum (D. albiventris). Brazilian opossums are probably infected by different Sarcocystis spp. distinct from S. neurona and S. falcatula, or present a high level of genetic recombination.

Occurrence and first molecular characterization of Sarcocystis spp. in wild boars (Sus scrofa) and domestic pigs (Sus scrofa domesticus) in Romania: Public health significance of the isolates

Domestic and wild pigs, as intermediate hosts, can harbor tissue cysts of three Sarcocystis species namely S. miescheriana, S. suihominis and S. porcifelis. Out of them, S. suihominis is zoonotic. Romania is a country with high consumption of raw and/or undercooked traditional pork products. This fact may greatly favor the acquiring of the zoonotic Sarcocystis infections by humans, as definitive host. Based on this consideration and in order to investigate the occurrence and public health significance of Sarcocystis spp. in two western counties (Caraş-Severin and Timiş) of Romania, a total of 165 heart samples from hunted wild boars (Sus scrofa, n=101) and home slaughtered domestic pigs (Sus scrofa domesticus, n=64) were screened using microscopic fresh examination and molecular methods. Microscopic examination revealed the presence of sarcocysts in 60.4% of wild boars, and 23.4% of domestic pigs. Genetic characterization of isolates through the PCR-RFLP procedure, targeting the 18S rRNA gene, was successfully achieved for all microscopically positive samples, indicating the presence of a single species, S. miescheriana, in both hosts. The identity of 13 selected S. miescheriana isolates was also confirmed through sequencing. The tested hosts older than 27 months were found to be significantly higher infected (p<0.05) with Sarcocystis than the 6 to ≤27months age group. Although the human infective S. suihominis has not been registered, for a more reliable epidemiological picture, further molecular studies enrolling a larger number of animals and diagnosis on human intestinal Sarcocystis infections are still necessary.

Sarcocystis sp.-Associated Meningoencephalitis in a Bald Eagle (Haliaeetus Leucocephalus)

Protozoal meningoencephalitis is uncommon in raptors. An adult female bald eagle ( Haliaeetus leucocephalus) was euthanized after several months of treatment for progressive neurologic signs. The predominant histologic lesion was lymphoplasmacytic and histiocytic meningoencephalitis involving the cerebrum and cerebellum. There was a marked segmental loss of granular cells and Purkinje cells, as well as segmental atrophy of the molecular layer in the cerebellum. Protozoal merozoites and schizonts were observed in the gray matter of the cerebellum. Ultrastructurally, the merozoites were classified as a species of Sarcocystis due to the lack of rhoptries. Immunohistochemistry of the agent revealed a positive reaction for Sarcocystis neurona, while sections were negative for Toxoplasma gondii and Neospora caninum. Sarcocystis sp. infection should be considered as a differential diagnosis in bald eagles with chronic neurologic disease.

Prevalence and first molecular identification of Sarcocystis species in cattle and water buffaloes in India

The importance of Sarcocystis hominis in causing zoonotic infections is well known. Recently, S. hominis like cysts have been reported from water buffalo in China. Previous studies indicate prevalence of Sarcocystis species in bovine populations in India but molecular evidence is required for proper species differentiation. We examined two hundred and ninety six cardiac tissue samples of Indian water buffaloes and cattle from northern and western parts of the country. Tissues were examined for Sarcocystis using intact cyst isolation method, pepsin acid digestion method and Sarcocystis 18S rRNA PCR. The combination of primers was used for 18S rRNA PCR amplification followed by sequencing. Twenty five representative samples were sent for sequencing and 19 readable sequences were obtained for phylogenetic analysis. Overall, the Sarcocystis cysts/zoites were recorded in 44% (95% CI 38-49%), 58% (95% CI 53-64%) and 68% (95% CI 63-73%) from both cattle and buffalo samples using intact cyst isolation, pepsin-HCl digestion method and conventional PCR, respectively. The results indicate that pepsin-HCl digestion method and conventional PCR are more sensitive than intact cyst isolation for detection of Sarcocystis species in tissue samples. The prevalence of Sarcocystis species was high in buffalo as compared to cattle intermediate hosts. Phylogenetic analysis indicated that more than one Sarcocystis species are circulating in cattle and water buffaloes in India. The results further indicate that experimental transmission studies are required to re-confirm the identities and host ranges of the Sarcocystis species in cattle and water buffaloes in India.

Concurrent Presence of Sarcocystis Neurona Sporocysts, Besnoitia Darlingi Tissue Cysts, and Sarcocystis Inghami Sarcocysts in Naturally Infected Opossums (Didelphis Virginiana)

Opossums ( Didelphis virginiana) are exposed to a wide range of coccidia through feeding on a variety of foods, including, but not limited to, carrion, insects, and nestling birds. Abundant D. virginiana populations in urban and suburban areas can be important reservoirs of parasitic infection because of their profuse and prolonged excretion of the sporocysts of several species of Sarcocystis, their omnivorous diet, and their relatively long life span. This report describes 2 adult female opossums found to be simultaneously infected with the tissue cysts of Besnoitia darlingi, sarcocysts of Sarcocystis inghami, as well as with the intestinal sporocysts of S. neurona. Cysts typical of B. darlingi based on gross, histological, and ultrastructural characteristics were disseminated throughout the visceral organs, musculature, ears, and skin. The S. neurona and B. darlingi infections were confirmed by comparative sequence analysis of polymerase chain reaction—amplified diagnostic genetic loci. Sarcocysts of S. inghami are also described. Such examples of multiple parasitic infections show that concurrent infections occur naturally. The propensity for species to coexist should be considered in the differential diagnosis of tissue cyst—forming coccidian protozoa and may have important epidemiological and evolutionary implications.

Effects of Blood Contamination of Cerebrospinal Fluid on Results of Indirect Fluorescent Antibody Tests for Detection of Antibodies against Sarcocystis Neurona and Neospora Hughesi

The purpose of this study was to determine the effect of blood contamination of cerebrospinal fluid (CSF) on the results of indirect fluorescent antibody tests (IFATs) for Sarcocystis neurona and Neospora hughesi. The in vitro study used antibody-negative CSF collected from non-neurologic horses immediately after euthanasia and blood samples from 40 healthy horses that had a range of IFAT antibody titers against S. neurona and N. hughesi. Serial dilutions of whole blood were made in seronegative CSF to generate blood-contaminated CSF with red blood cell (RBC) concentrations ranging from 10 to 100,000 RBCs/μl. The blood-contaminated CSF samples were then tested for antibodies against both pathogens using IFAT. Blood contamination of CSF had no detectable effect on IFAT results for S. neurona or N. hughesi at any serologic titer when the RBC concentration in CSF was <10,000 RBCs/μl. At concentrations of 10,000-100,000 RBCs/μl of CSF, positive CSF results (IFAT titer ≥5) for S. neurona and N. hughesi were detected only when the corresponding serum titers were ≥160 and ≥80, respectively. The IFAT performed on CSF is reliable for testing horses for equine protozoal myeloencephalitis caused by S. neurona or N. hughesi, even when blood contamination causes the RBC concentration in CSF to be up to 10,000 RBCs/μl.

Accipiter hawks (Accipitridae) confirmed as definitive hosts of Sarcocystis turdusi, Sarcocystis cornixi and Sarcocystis sp. ex Phalacrocorax carbo

Sarcocystis is a large genus of protozoan parasites with complex heteroxenous life cycles. For many species, either the intermediate or the definitive host is still unknown. In this study, 116 Accipiter hawks (Eurasian sparrowhawks and northern goshawks) were investigated for the presence of Sarcocystis spp. in their intestinal tract or their faeces. To gain a wide distribution, samples were collected throughout Germany within 2 years. It was possible to detect Sarcocystis-like oocysts in 65 samples. Sequencing of the ITS region or species-specific PCR identified 33 samples as Sarcocystis turdusi/Sarcocystis sp. ex A. nisus (18), Sarcocystis calchasi (6), Sarcocystis columbae (3), Sarcocystis cornixi (3) and Sarcocystis sp. ex Phalacrocorax carbo (3). Besides the known infestation with S. columbae, S. sp. ex A. nisus and S. calchasi the Accipiter hawks were thereby confirmed as definitive host of S. turdusi, S. cornixi and S. sp. ex Phalacrocorax carbo for the first time.

Morphologic and molecular characteristics of Sarcocystis atraii n. sp. (Apicomplexa: Sarcocystidae) infecting the common coot (Fulica atra) from Egypt

A single morphologic type of Sarcocystis cysts found in two out of 43 examined common coots, Fulica atra, is considered to represent a new species for which the name Sarcocystis atraii n. sp. is proposed and its description is provided. Coots were hunted from the vicinity of Brolos Lake located at KafrElsheikh province, Egypt. The structural morphology of the revealed sarcocysts was described using light and transmission electron microscopy. Sarcocysts were found in the leg and thigh muscles. The cysts were microscopic and measured 165-850 μm in length × 50-85 μm in width. Histologically; the sarcocyst wall was wavy and had minute undulations. Ultrastructurally, it measured 1-3 μm in thickness and possessed many mushroom-like villar protrusions sometimes originating from other mushroom-like villar protrusions that measured approximately 0.5-2 μm in length and up to 2 μm in width, with the presence of electron dense ground substance of 300 nm to 1 μm thick. The bradyzoites were elongated, banana-shaped and measured 7.5-14 × 1.5-2.5 μm, with centrally or terminally located nuclei. The ultrastructural features of the cyst wall belonged to type 24. On the basis of sequencing and phylogenic analyses for 18S rRNA , 28S rRNA genes and ITS-1 region; S. atraii n. sp. is considered a genetically distinct species, being most closely related to avian Sarcocystis spp. whose definitive hosts are predatory mammals.

Light microscopy and molecular identification of Sarcocystis spp. in meat producing animals in Selangor, Malaysia

One thousand and forty-five tissue samples of skeletal muscles, tongue, heart, diaphragm and esophagus were collected from 209 animals (43 sheep, 89 goats and 77 cattle) from an abattoir in Selangor between February and October, 2013. Each sample was divided into three pieces with each piece measuring 2-3 mm3. Each piece was then squeezed between two glass slides and examined microscopically at x 10 magnification for the presence of sarcocystosis. Three positive samples from each animal species were then fixed in 10% formalin for histological processing. Seven positive samples collected from each animal species were preserved at -80°C or 90% ethanol for gene expression studies. Microsarcocysts were detected in 114 (54.5%) animals by light microscopy (LM). The infection rates in sheep, goat and cattle were 86, 61.8 and 28.6% respectively. The highest rate of infection was in the skeletal muscles of sheep (64.9%) and goats (63.6%) and in the heart of cattle (63.6%). The cysts were spindle to oval in shape and two stages were recognized, the peripheral metrocytes and centrally located banana-shaped bradyzoites. 18S rRNA gene expression studies confirmed the isolates from the sheep as S. ovicanis, goats as S. capracanis and cattle as S. bovicanis. This, to the best of our knowledge, is the first molecular identification of an isolate of S. ovicanis and S. capracanis in Malaysia. Further studies with electron microscopy (EM) are required in the future to compare the features of different types of Sarcocysts spp.

Neglected tropical diseases among two indigenous subtribes in peninsular Malaysia: highlighting differences and co-infection of helminthiasis and sarcocystosis

Soil-transmitted helminth (STH) infections have been documented among these minority groups since 1938. However the prevalence of STH is still high among these communities. Most studies tend to consider the Orang Asli (indigenous) as a homogenous group. In contrary, different subtribes have their own cultural practices. To understand this variation better, we studied the prevalence and associated factors of STH and other gut parasitic infections among two common subtribes (i.e. Temuan and Temiar). Results showed that the prevalence of the overall STH infections was higher in the Temuan subtribe (53.2% of 171) compared to the Temiar subtribe (52.7% of 98). Trichuris trichiura (46.2%) was the most prevalent parasite in the Temuan subtribe, followed by Ascaris spp. (25.7%) and hookworm (4.1%). In contrast, Ascaris spp. (39.8%) was more prevalent among the Temiar subtribe, preceded by T. trichiura (35.7%) and finally hookworm (8.3%). There were also co-infections of helminthiasis and intestinal protozoa among both Temuan and Temiar subtribes with rates being three times higher among the Temiar compared to Temuan. The most common co-infection was with Entamoeba histolytica/dispar/moshkovskii (n = 24; 24.5%, 16.0-33.0), followed by Giardia spp. (n = 3; 3.1%, -0.3-6.5). In Temuan, STH infection individuals were also infected with Entamoeba histolytica/dispar/moshkovskii (n = 11; 6.4%, 5.0-13.8), Cryptosporidium spp. (n = 3, 1.8%, -0.2-3.8) and Giardia spp. (n = 2, 1.2%, -0.4-2.8). In comparison, there was no Cryptosporidium spp. detected among the Temiar. However, it was interesting to note that there was an occurrence of co-infection of intestinal helminthiasis and sarcocystosis (intestinal) in a Temiar individual. The last report of sarcocystosis (muscular) among the Orang Asli was in 1978. The present study highlighted the importance of understanding the variation of infections amongst the different Orang Asli subtribes. It is vital to note these differences and use this knowledge to customise effective control measures for the various subtribes.

Microscopic and molecular characterization of Hepatozoon domerguei (Apicomplexa) and Foleyella furcata (Nematoda) in wild endemic reptiles from Madagascar

Madagascar is one of the world's top twelve "megadiversity" hot spots hosting unique and threatened flora and fauna. Parasites are a major component of biodiversity but remain largely uncharacterized in wildlife. In this study we combine microscopic and molecular assessment of hemoparasites in endemic reptile species from Madagascar. We detected three distinct parasites: the apicomplexans Hepatozoon and Sarcocystis, and filarial nematodes. The prevalence and intensity of these apicomplexans were low overall, while microfilarial infections in chameleons were relatively high. We detected mixed infections of two Hepatozoon haplotypes in Madagascarophis colubrinus, and of Hepatozoon and microfilariae in a Furcifer sp. Phylogenetic analyses of Hepatozoon showed evidence of prey-predator transmission, with identical sequences found in the snakes M. colubrinus and Ithycyphus oursi, and their prey Furcifer sp. Based on previous studies regarding the life cycle of Hepatozoon domerguei Landau, Chabaud, Michel, and Brygoo, 1970 in these hosts and due to their morphological similarity, we propose that this Hepatozoon haplotype is Hepatozoon domerguei. Future studies, including the examination of invertebrate hosts, are needed to verify this preliminary taxonomic identification. A distinct hemogregarine haplotype was found in Oplurus sp., which displayed morphologically different gametocytes, some of which were apparently inside leukocytes. The Sarcocystis identified from Tracheloptychus petersi was identical to that reported in a North African snake, indicating that the same lineage is found in geographically distinct regions. By combining morphological and genetic information, Foleyella furcata (Linstow, 1899) filarial nematodes were identified in several Furcifer chameleons. This study provides insights into the distribution, diversity and host-parasite interactions of hemoparasites in wild reptile populations from Madagascar.

Outbreak of human infection with Sarcocystis nesbitti, Malaysia, 2012

An outbreak of fever associated with myalgia and myositis occurred in 2012 among 89 of 92 college students and teachers who visited Pangkor Island, Malaysia. The Sarcocystis nesbitti 18S rRNA gene and sarcocysts were obtained from muscle tissues of 2 students. Our findings indicate emergence of S. nesbitti infections in humans in Malaysia.

Acute muscular sarcocystosis: an international investigation among ill travelers returning from Tioman Island, Malaysia, 2011-2012

BACKGROUND

Through 2 international traveler-focused surveillance networks (GeoSentinel and TropNet), we identified and investigated a large outbreak of acute muscular sarcocystosis (AMS), a rarely reported zoonosis caused by a protozoan parasite of the genus Sarcocystis, associated with travel to Tioman Island, Malaysia, during 2011-2012.

METHODS

Clinicians reporting patients with suspected AMS to GeoSentinel submitted demographic, clinical, itinerary, and exposure data. We defined a probable case as travel to Tioman Island after 1 March 2011, eosinophilia (>5%), clinical or laboratory-supported myositis, and negative trichinellosis serology. Case confirmation required histologic observation of sarcocysts or isolation of Sarcocystis species DNA from muscle biopsy.

RESULTS

Sixty-eight patients met the case definition (62 probable and 6 confirmed). All but 2 resided in Europe; all were tourists and traveled mostly during the summer months. The most frequent symptoms reported were myalgia (100%), fatigue (91%), fever (82%), headache (59%), and arthralgia (29%); onset clustered during 2 distinct periods: "early" during the second and "late" during the sixth week after departure from the island. Blood eosinophilia and elevated serum creatinine phosphokinase (CPK) levels were observed beginning during the fifth week after departure. Sarcocystis nesbitti DNA was recovered from 1 muscle biopsy.

CONCLUSIONS

Clinicians evaluating travelers returning ill from Malaysia with myalgia, with or without fever, should consider AMS, noting the apparent biphasic aspect of the disease, the later onset of elevated CPK and eosinophilia, and the possibility for relapses. The exact source of infection among travelers to Tioman Island remains unclear but needs to be determined to prevent future illnesses.

Prevalence of Sarcocystis spp. and Hammondia spp. microcysts in esophagus tissue of sheep and cattle, emphasized on their morphological differences

Sarcocystis and Hammondia are two obligatory protozoan parasites. These genera belong to cyst-forming coccidia group of the phylum Apicomplexa. They both need two different hosts to complete their life cycles. Felids and canids can act as definitive hosts, while herbivores, such as sheep and cattle, are the most important intermediate hosts. Reports verify that no important disease has been caused by Hammondia spp.; on the other hand, Sarcocystis spp. can cause some severe infectious disease in livestock industry such as abortion. Economic losses are another concern due to carcass condemnation during meat inspection in abattoirs and decrease in the quality and quantity of milk and wool production. Due to the Sarcocystis and Hammondia tissue cysts being similar, the distinction between these different genera is so important. In this study, the prevalence of Sarcocystis and Hammondia in the esophagus tissue of sheep and cattle slaughtered in one of the industrial abattoir in Iran was reported and an easy and rapid method for accurate diagnosing of Sarcocystis and Hammondia bradyzoites was explained.

Molecular identification of Sarcocystis hominis in native cattle of central Iran: a case report

Sarcocystis spp. are two-host protozoan parasites belonging to the phylum Apicomplexa. Among different known species of Sarcocystis in cattle, only Sarcocystis hominis is important from the public health viewpoint, because of its zoonotic characteristics. This study presents the first molecular identification of S. hominis in native cattle in central Iran. A sample of diaphragm muscle from a 6-year-old native cow slaughtered at Yazd Slaughterhouse, Yazd, central Iran, was collected in May 2013. DNA extraction was performed, using the salting-out method. DNA purification and precipitation were performed consecutively. The amplicon and digestion results were analyzed using agarose gel electrophoresis. A PCR product with 926 bp in length was obtained after amplification, and 376 bp and 550 bp in length after digestion that identified S. hominis. To the best of our knowledge, this study is the first of its kind to be reported from Iran.

High prevalence of muscular sarcocystosis in cattle and water buffaloes from Selangor, Malaysia

The prevalence of sarcocystosis in cattle and water buffaloes from peninsular Malaysia was investigated in abattoirs in Selangor state, February, 2011, to March, 2012. Fresh muscle samples were collected from the tongue, heart, oesophagus, diaphragm and skeletal muscles of 102 cattle and 18 water buffaloes. Each sample was initially screened by light microscopy and then fixed for further histopathological analysis. Out of 120 animals examined, 49 (40.8%) harboured the microscopic type of Sarcocystis spp. The positivity rate for cattle was 36.2% and for water buffaloes 66.7%. In cattle, the organs highly infected were the skeletal muscles and diaphragm (27% each), followed by tongue and esophagus (24.3% each), and the heart (8%). In water buffaloes, the heart was most often infected (66.7%), followed by the oesophagus (50%) and skeletal muscle (33.3%); no sarcocysts were detected in the tongue and diaphragm. The shape of the sarcocyst was fusiform to oval with a mean cyst size of 151.66 x 75.83 μm and wall thickness of 2.47 μm in cattle, and 114 x 50.81 μm cyst size and the wall thickness of 1.11 μm in water buffaloes, consistent with Sarcocystis cruzi and Sarcocystis levinei, respectively. Remaining tissue from cattle was subjected to parasite specific 18S rRNA gene PCR and Sarcocystis cruzi was confirmed, at least exemplarily. The peripheral metrocytes and the banana-shaped bradyzoites (15.23 x 2.2 μm in cattle and 11.49 x 2.45 μm in water buffalo hosts) were easily recognized. In conclusion, a high positivity rate was found in Malaysian meat-producing animals with possible implications for meat consumption and human health.

Human and animal invasive muscular sarcocystosis in Malaysia--recent cases, review and hypotheses

Sarcocystosis, an unusual parasitic zoonotic disease, is caused by coccidian/ apicomplexan protozoa in humans and animals. The parasites usually develop in a heteroxenous predator-prey life-cycle involving final (carnivore) and intermediate (omnivore/herbivore) hosts. Besides the intestinal, non-invasive form of the disease in which humans and animals are the definitive hosts for certain Sarcocystis spp., the invasive form has come to recent attention. In the latter, humans and animals serve as intermediate host harbouring sarcocysts in their muscle tissue. Already in 1991 sarcocystosis was seen as a potential emerging food borne zoonosis in Malaysia, and in 2011 and 2012 the largest cluster of symptomatic human muscular sarcocystosis world-wide was reported from Tioman Island, Pahang state. In this review, we focus on invasive sarcocystosis in humans and animals in Malaysia, review the recorded cases and epidemiology, and present hypotheses.

Ongoing outbreak of an acute muscular Sarcocystis-like illness among travellers returning from Tioman Island, Malaysia, 2011-2012

As of 4 November, 2012, 100 patients with an acute muscular Sarcocystis-like illness associated with travel to Tioman Island, Malaysia, have been identified. Thirty-five travelled there mostly during July and August 2011 and 65 mostly during July and August 2012, suggesting an ongoing outbreak. Epidemiological investigations are ongoing. Public health agencies and practicing clinicians should be aware of this rarely-reported disease in humans and consider it as differential diagnosis in travellers returning from Tioman Island.

Centers for Disease Control and Prevention (CDC). Notes from the field: acute muscular sarcocystosis among returning travelers - Tioman Island, Malaysia, 2011

GeoSentinel (the surveillance program of the International Society of Travel Medicine and CDC) has identified 32 cases of suspected acute muscular sarcocystosis in travelers returning from Tioman Island off the east coast of peninsular Malaysia. All the patients traveled to Tioman Island during the summer of 2011. Within days or weeks of returning home, all experienced fever and muscle pain, often severe and prolonged. All had peripheral eosinophilia, and most had elevated serum creatinine phosphokinase levels. Most were tested for acute trichinosis and toxoplasmosis by serology, and all of these tests were negative. Approximately half of the patients were identified in Germany; others were reported elsewhere in Europe, and in North America and Asia. Muscle biopsy from two patients demonstrated organisms consistent with sarcocystosis, one from a group of five ill travelers and one from a group of three.

Laryngeal sarcocystosis accompanying laryngeal squamous cell carcinoma: case report and literature review

Laryngeal sarcocystosis is an uncommon zoonotic coccidian protozoal infestation of human beings. The authors reviewed the pathology of 1,063 laryngeal biopsies over the past 10 years (2000 to 2009). Only one case of laryngeal sarcocystosis accompanying laryngeal squamous cell carcinoma was identified. The overall prevalence of laryngeal sarcocystosis was 0.094%. The case was a 66-year-old man who presented with voice hoarseness for six months. Physical examination and computed tomography revealed an ulcerative exophytic mass on the right true vocal cord, suggestive of laryngeal carcinoma. He underwent a right frontolateral partial laryngectomy. Histopathology showed a nonkeratinizing squamous cell carcinoma with Sarcocystis spp in the vocalis muscle. He was followed up and enrolled in speech therapy. The authors briefly review the clinicopathologic features and pathogenesis of muscular sarcocystosis and concurrent laryngeal sarcocystosis and squamous cell carcinoma.

Ultrastructural and molecular characterization of Sarcocystis isolated from camel (Camelus dromedarius) in Iran

Sarcocystis cameli was first described in one-humped camels (Camelus dromedarius), and it is the only species which have so far reported in camels. Although more than 150 species of Sarcocystis were described in various animals, only a few data on camel Sarcocystis ultrastructure were published, and this report is the first for molecular information (DNA sequence and RLFP digestion pattern). The main objective of the present work is to characterize Sarcocystis isolated from camels by electron microscopy and PCR-RFLP methods. Muscle samples were taken from the fresh esophagus, diaphragm, skeletal muscles, and heart of one-humped camels (C. dromedarius) slaughtered in abattoirs of Tehran and Ghazvin provinces, Iran. The dissection and trypsin digestion techniques were applied for the detection of the cysts. The infected samples were fixed in glutaraldehyde and/or frozen at -20°C until use for ultrastructural and molecular studies, respectively. The ultrastructural and molecular studies were carried out contemporaneously. The 18S rRNA gene of the parasites was amplified by PCR. The PCR products were cloned into a pTZ57R/T and sequenced. In addition, the PCR products were digested separately with each of the four restriction enzymes for RFLP. Our results indicated that only microcysts were observed in muscle samples. The microcysts were white, elongated, spindled, and a few spiral-shaped, with mean size 260 × 75 μm which are identical with S. cameli. The ultrastructure of microcyst wall had many non-branched finger-like protrusions irregularly folded. There was a 600-bp specific band amplified after PCR with specific primers. The molecular data for camel Sarcocystis is reported for the first time in Iran and the world.

Polyparasitism is associated with increased disease severity in Toxoplasma gondii-infected marine sentinel species

In 1995, one of the largest outbreaks of human toxoplasmosis occurred in the Pacific Northwest region of North America. Genetic typing identified a novel Toxoplasma gondii strain linked to the outbreak, in which a wide spectrum of human disease was observed. For this globally-distributed, water-borne zoonosis, strain type is one variable influencing disease, but the inability of strain type to consistently explain variations in disease severity suggests that parasite genotype alone does not determine the outcome of infection. We investigated polyparasitism (infection with multiple parasite species) as a modulator of disease severity by examining the association of concomitant infection of T. gondii and the related parasite Sarcocystis neurona with protozoal disease in wild marine mammals from the Pacific Northwest. These hosts ostensibly serve as sentinels for the detection of terrestrial parasites implicated in water-borne epidemics of humans and wildlife in this endemic region. Marine mammals (151 stranded and 10 healthy individuals) sampled over 6 years were assessed for protozoal infection using multi-locus PCR-DNA sequencing directly from host tissues. Genetic analyses uncovered a high prevalence and diversity of protozoa, with 147/161 (91%) of our sampled population infected. From 2004 to 2009, the relative frequency of S. neurona infections increased dramatically, surpassing that of T. gondii. The majority of T. gondii infections were by genotypes bearing Type I lineage alleles, though strain genotype was not associated with disease severity. Significantly, polyparasitism with S. neurona and T. gondii was common (42%) and was associated with higher mortality and more severe protozoal encephalitis. Our finding of widespread polyparasitism among marine mammals indicates pervasive contamination of waterways by zoonotic agents. Furthermore, the significant association of concomitant infection with mortality and protozoal encephalitis identifies polyparasitism as an important factor contributing to disease severity in marine mammals.

Severity of toxoplasmosis, a water-borne zoonosis, varies widely from chronic and benign to acutely fatal. Here, we investigate polyparasitism (infection with multiple parasite species) as one factor governing the spectrum of disease in Toxoplasma gondii infections. This study utilized wild marine mammals as sentinels to detect contamination of waterways by T. gondii and a similar protozoan, Sarcocystis neurona, which have been linked to water-borne outbreaks in humans and wildlife along North America's Pacific Coast. Using genetic tools, we found high rates of protozoal infection, predominantly concomitant infections, in animals inhabiting major waterways of the Pacific Northwest. These dual infections of T. gondii and S. neurona were more frequently associated with mortality and protozoal encephalitis than single infections, indicating a role for polyparasitism in disease severity. Finally, rare T. gondii genotypes linked to a major human outbreak in the Pacific Northwest were abundant in marine mammals of the region, emphasizing wildlife as relevant sentinels for evaluation of human health risks. Our data implicate polyparasitism as a critical factor associated with the severity of protozoal disease. We also identify the need for vigilant surveillance of public waterways to prevent fecal contamination recurrently threatening human and wildlife health along the Pacific coast.

Sarcocystis lindsayi-like (Apicomplexa: Sarcocystinae) of the opossum (Didelphis aurita) from Southeastern Brazil

Sporocysts of Sarcocystis were obtained from intestinal scrapings of three out of five opossums (Didelphis aurita) trapped in the southeastern region, of the State of Rio de Janeiro, Brazil. Fifteen caged budgerigars (Melopsittacus undulatus) received, orally, twenty-six sporocysts in 500 mL PBS, but only five belonging to one of the groups developed clinical signs, that consisted of anorexia, lethargy, ruffled feathers and dyspnoea, and parasitism in tissues. Two of the five budgerigars died on the 25th and 29th days after infection (DAI). The other three budgerigars were posted on the 30th DAI. In all the five infected birds were observed meronts in the capillaries of the lungs and cysts in muscles, mainly in the tongue and legs.

Comparative morphological studies on three Sarcocystis species in Sohag, Egypt

Samples from the tongue, heart, oesophageal and skeletal muscles were collected from 100 cow and 100 buffalo from Sohag slaughterhouses. Macroscopic examination for sarcocysts was followed by microscopic ones on impression smears and compressed muscles. Histological sections and transmission electron microscope (TEM) studies were done on positive cases. Sarcocystis infection rate of cows were 84%. Two species of Sarcocystis were detected: 1- S. cruzi with a membrane provided with hair-like villar protrusions folded over the surface of the cyst. These protrusions were rod-like, round, oval or irregular in shape and were approximately parallel to the cyst surface. 2-S. hominis characterized by a cyst wall consisting of cylindrical finger-like villar protrusions and having microfilaments. The protrusions were perpendicular on the cyst surface with broad tips and contain microfilaments. Buffaloes' muscle samples revealed an infection rate of 28%. The macroscopic fusiform-shaped species only was detected (Sarcocystis fusiformis). The role of cyst wall ultrastructure and thickness were discussed regarding identification and pathogenicity.

Giardia spp. and Sarcocystis spp. status in pet dogs of Shiraz, Southern part of Iran

A study was carried out in order to find out the status of Giardia spp. and Sarcocystis spp. in pet dogs and stray cats of Shiraz, Fars Province of Iran. Faecal samples of 147 pet dogs and 112 stray cats of different age groups, breeds, and sexes were tested. The stools were examined with the following techniques: direct faecal smears using normal saline, zinc sulfate flotation and formalin-ether concentration technique. Out of a total of 147 pet dogs examined, only one case (0.68%) of Giardia spp. was observed. A total of 3 (2.04%) pet dogs were found positive for Sarcocystis spp. Specimens from stray cats were also examined, however no Giardia spp. trophozoite or cyst was observed in these specimens.

Fast food hamburgers: what are we really eating?

Americans consume about 5 billion hamburgers a year. It is presumed that most hamburgers are composed primarily of meat. The purpose of this study is to assess the content of 8 fast food hamburger brands using histologic methods. Eight different brands of hamburgers were evaluated for water content by weight and microscopically for recognizable tissue types. Glial fibrillary acidic protein (GFAP) staining was used to evaluate for brain tissue. Water content by weight ranged from 37.7% to 62.4% (mean, 49%). Meat content in the hamburgers ranged from 2.1% to 14.8% (median, 12.1%). The cost per gram of hamburger ranged from $0.02 to $0.16 (median, $0.03) and did not correlate with meat content. Electron microscopy showed relatively preserved skeletal muscle. A variety of tissue types besides skeletal muscle were observed including connective tissue (n = 8), blood vessels (n = 8), peripheral nerve (n = 8), adipose tissue (n = 7), plant material (n = 4), cartilage (n = 3), and bone (n = 2). In 2 hamburgers, intracellular parasites (Sarcocystis) were identified. The GFAP immunostaining was not observed in any of the hamburgers. Lipid content on oil-red-O staining was graded as 1+ (moderate) in 6 burgers and 2+ (marked) in 2 burgers. Fast food hamburgers are comprised of little meat (median, 12.1%). Approximately half of their weight is made up of water. Unexpected tissue types found in some hamburgers included bone, cartilage, and plant material; no brain tissue was present. Sarcocystis parasites were discovered in 2 hamburgers.

[Experimental infection of Sarcocystis suihominis in pig and human volunteer in Guangxi]

OBJECTIVE

To confirm existence of Sarcocystis suihominis and possible transmission cycle between human and pigs.

METHODS

Based on the human-pig-human infection cycle of Sarcocystis suihominis, feces of naturally infected pigs were collected and over 10,000 sporocysts were received by flotation technique, which were mixed with fodder to infect a normal pig. Fresh pork meat containing mature sarcocysts was chopped into pieces and swallowed by a volunteer (the first author of this paper) with about 71,000 sporocysts. Symptoms and development of the parasites after infection were observed.

RESULTS

The volunteer showed abdominal distension in about 5 hours after infection, with watery diarrhea 13 times from the 8th to 36th hour, vomiting 4 times, chilling and fever with a temperature of 38.5 degrees C, dizziness, headache, joint and muscle ache, epigastralgia, and anorexia. Un-sporized sporocysts were found in the faces 10 days after infection and sporocysts appeared on the 12th day. The average size of sporocysts was 11.9 (8.8-14.5) microm x 9.2 (7.5-12.5) microm. The infected pig showed a slight anorexia, fatigue, constipation, hair loosen in 5-8 days after infection, and returned normal on the 17th day. The average size of the sarcocysts was 299.2 (175-575 ) microm x 62.3 (30-102.5) microm. Size of bradyzoites was 11.5 (9.5-13.5) microm x 4.1 (2.8-5.0) microm. The volunteer was treated with acetylspiramycin for 15 days (0.2 g/time, 4 times/d) after 46 days of infection, and fecal examination turned negative 30 days later.

CONCLUSION

There is a man-pig cycle for Sarcocystis suihominis in Guangxi.

The Sarcocystis-cyst containing beef and pork as the sources of natural intestinal sarcocystosis in Thai people

BACKGROUND

Human intestinal sarcocystosis is a zoonotic disease caused by two coccidians, i.e. Sarcocystis fusiformis (syn. S. bovihominis, S. hominis) due to consumption of raw infected beef and Sarcocystis meischeriana (syn. S. suihominis) due to consumption of infected raw pork. In 1987, survey of the macroscopic S. fusiformis cysts in market beef mainly from old water buffalos aged more than 15 years were commonly observed in Bangkok. In 2005, the macroscopic cyst was no longer seen in beef of cattle and water buffalo aged less than three years.

OBJECTIVE

The epidemiological investigation of Sarcocystis spp. infected meat in Bangkok and Lampang.

MATERIAL AND METHOD

Samples for each of the tongue and beef of cattle and water buffalo, pork from Bangkok markets and pork of domestic swine from some remote villages in various subprovinces (Ampurs) in Lampang were obtained for microscopic examination by H and E and selectively by PAS staining.

RESULTS

The microscopic S. fusiformis cysts were seen in all five specimens of tongues and ten specimens of muscles of cattle and water buffalo obtained from fresh-food markets in Bangkok. Ten samples of pork from Bangkok markets revealed no coccidian infection. The microscopic S. meischeriana cysts were seen in three specimens of swine muscles collected from two subprovinces in Lampang.

CONCLUSION

The present merozoites in coccidian cysts retrieved from beef and pork are similar to those previously observed in human intestine. This may histologically indicate an invasive sarcocystosis by both species leading to a condition presently known as chronic inflammation of undetermined etiology in man.

Morphological and molecular identification of three species of Sarcocystis in reindeer (Rangifer tarandus tarandus) in Iceland

Six Sarcocystis species have previously been described from reindeer in Norway based on sarcocyst morphology and DNA sequencing. The aim of this study was to determine whether reindeer in Iceland, which descend from reindeer imported from Norway in 1787, also were infected with Sarcocystis, and to identify and genetically characterise any species present. Muscle tissue from the heart, diaphragm and/or oesophagus was collected from 36 reindeer in Iceland. Pieces of all tissue samples were examined histologically. Frozen/thawed samples of cardiac muscle, oesophagus and/or diaphragm from 11 of the 36 reindeer were also examined under a stereoscopic microscope and sarcocysts present were identified to species either in situ or under a light microscope. Two cysts of each species, originating from two different reindeer were randomly selected for DNA analyses. The complete ssu rRNA gene was amplified by the polymerase chain reaction (PCR) and sequenced. In addition, two sarcocysts that could not be classified by microscopic examination were selected for partial ssu rRNA gene sequence analysis. By histology, sarcocysts were found in the diaphragm and/or oesophagus of 8 of 36 (22.2%) animals. By examination of fresh tissue, sarcocysts of Sarcocystis rangi, S. tarandivulpes and S. hardangeri were found in the oesophagus of seven of nine (77.8%) animals, suggesting a high prevalence of Sarcocystis in the Icelandic reindeer population. Cyst morphology and the ssu rRNA gene sequence of each of the three species were identical to isolates of the same species from Norwegian reindeer. DNA sequencing was useful in order to identify cysts with an ambiguous morphology. This is the first record of these Sarcocystis species in reindeer outside Norway.

Molecular-based identification of Sarcocystis hominis in Belgian minced beef

Sarcocystis hominis, one of the three species of Sarcocystis that cause muscular cysts in cattle, is a protozoan parasite that can infect the human intestinal tract. The objective of the present study was to develop a new molecular identification method capable of discriminating among the bovine Sarcocystis species and to apply this tool in combination with stereomicroscopy to determine the presence of Sarcocystis spp. in minced beef in Belgium, with special attention to Sarcocystis hominis. A PCR technique based on the 18S rRNA sequence and by sequencing of the amplicon was highly specific. Sequence analysis of PCR products from thick-walled cysts collected from minced beef in Belgium revealed that S. hominis was present in 97.4% of the samples. Because the consumption of raw minced beef is common in Belgium and certain other European countries, these findings may point to an underestimated risk to public health.