A Novel CARMIL2 Immunodeficiency Identified in a Subset of Cavalier King Charles Spaniels with Pneumocystis and Bordetella Pneumonia.

Pet dogs are a valuable natural animal model for studying relationships between primary immunodeficiencies and susceptibility to Pneumocystis and other opportunistic respiratory pathogens. Certain breeds, such as the Cavalier King Charles Spaniel, are over-represented for Pneumocystis pneumonia (PCP), suggesting the presence of a primary immunodeficiency in the breed. Here, we report the discovery of a CARMIL2 nonsense variant in three Cavalier King Charles Spaniel dogs with either PCP (n = 2) or refractory Bordetella pneumonia (n = 1). CARMIL2 encodes a protein that plays critical roles in T-cell activation and other aspects of immune function. Deleterious CARMIL2 variants have recently been reported in human patients with PCP and other recurrent pneumonias. In addition to opportunistic respiratory infection, the affected dogs also exhibited other clinical manifestations of CARMIL2 deficiencies that have been reported in humans, including early-onset gastrointestinal disease, allergic skin disease, mucocutaneous lesions, abscesses, autoimmune disorders, and gastrointestinal parasitism. This discovery highlights the potential utility of a natural canine model in identifying and studying primary immunodeficiencies in patients affected by PCP.

Equus caballus papillomavirus type 2 (EcPV2)-associated benign penile lesions and squamous cell carcinomas.

BACKGROUND: Squamous cell carcinoma is the most common genital, ocular and gastric tumour in horses. Equus caballus papillomavirus type 2 (EcPV2) DNA has been detected in several studies in equine penile squamous cell carcinomas (SCCs) and precursor lesions providing evidence of a causal role of EcPV2 in equine genital SCCs. Recently, EcPV2 E6/E7 nucleic acids were also detected in equine gastric SCCs, but further studies are required to determine the role of EcPV2 infection in the pathogenesis of gastric SCC. EcPV2 nucleic acids have been rarely described in ocular SCCs and precursor lesions. OBJECTIVES: To investigate the presence of EcPV2 nucleic acids with polymerase chain reaction (PCR) and in situ hybridisation (ISH) in penile hyperplasias, papillomas and SCCs in horses and to determine whether EcPV2 nucleic acids can be detected in SCCs affecting other locations, including the stomach, ocular tissues and larynx. METHODS: Twenty-one archival formalin-fixed paraffin embedded (FFPE) tissue samples, including 12 genital lesions comprising penile hyperplasias, papillomas and SCCs, 6 ocular SCCs, 2 gastric SCCs and 1 laryngeal SCC, were screened by PCR and ISH for EcPV2 E6/E7 DNA and mRNA. Archival FFPE tissue samples (eyelid and penile mucosa and preputium) from six horses without a diagnosis or history of neoplastic or papillomavirus-associated disease were included as controls. RESULTS: EcPV2 nucleic acids were detected by PCR and ISH in all genital lesions (12/12) and gastric SCCs (2/2), in two ocular SCCs (2/6) and in one laryngeal SCC (1/1). In control horses, one eyelid sample was positive in PCR but not in ISH. The remaining control samples were negative for EcPV2 E6/E7 nucleic acids in PCR and ISH. CONCLUSIONS: These results further support the role of EcPV2 infection in the development of equine genital SCCs and suggest that EcPV2 infection may also act as a predisposing factor for other SCCs in horses, including gastric, ocular and laryngeal SCCs.

Adherent-invasive Escherichia coli associated with granulomatous colitis and extraintestinal dissemination in a Sphynx cat.

This case report describes a case of granulomatous colitis (GC) associated with adherent-invasive Escherichia coli (AIEC) with extension to cecum and ileum and dissemination to multiple lymph nodes, the spleen, and brain in a 10-year-old, male Sphynx cat. The cat had an episode of diarrhea 4 months prior to consultation due to sudden blindness. Signs rapidly progressed to ataxia, seizures, and death. Gross and histologic findings were consistent with granulomatous inflammation in all affected organs. In situ hybridization confirmed the presence of intracellular E. coli within enterocytes and infiltrating macrophages, and whole genome sequencing identified virulence traits commonly linked to AIEC strain. This is the first characterization of GC in a cat associated to AIEC resembling the metastatic form of Crohn's disease in humans and GC of dogs. Extraintestinal involvement might provide evidence of the ability of AIEC to promote granulomatous inflammation beyond the gut.

Label-free quantitative proteomics and immunoblotting identifies immunoreactive and other excretory-secretory (E/S) proteins of Anoplocephala perfoliata.

Anoplocephala perfoliata is a common tapeworm in horses causing colic and even mortalities. Current diagnostic tests to detect A. perfoliata infections have their limitations and an improved method is needed. Immunoreactive excretory/secretory proteins (E/S proteome) of this parasite can provide promising candidates for diagnostic tests. We compared E/S proteins produced by small (length < 20 mm, width < 5 mm) and large (length 20 to 40 mm, width 5 to 10 mm) A. perfoliata worms in vitro by label-free quantitative proteomics using a database composed of related Hymenolepis diminuta, Echinococcus multilocularis/granulosus and Taenia aseatica proteins for protein identifications. Altogether, 509 E/S proteins were identified after incubating the worms in vitro for three and eight hours. The greatest E/S proteome changes suggested both worm size- and time-dependent changes in cytoskeleton remodeling, apoptosis, and production of antigens/immunogens. The E/S proteins collected at the three-hour time point represented the natural conditions better than those collected at the eight-hour time point, and thereby contained the most relevant diagnostic targets. Immunoblotting using antibodies from horses tested positive/negative for A. perfoliata indicated strongest antigenicity/immunogenicity with 13-, 30- and 100-kDa proteins, involving a thioredoxin, heat-shock chaperone 90 (Hsp90), dynein light chain component (DYNLL), tubulin-specific chaperone A (TBCA) and signaling pathway modulators (14-3-3 and Sj-Ts4). This is among the first studies identifying new diagnostic targets and A. perfoliata antigens eliciting a IgG-response in horses.

Experimental Infection of Mink with SARS-COV-2 Omicron Variant and Subsequent Clinical Disease.

We report an experimental infection of American mink with SARS-CoV-2 Omicron variant and show that mink remain positive for viral RNA for days, experience clinical signs and histopathologic changes, and transmit the virus to uninfected recipients. Preparedness is crucial to avoid spread among mink and spillover to human populations.

Dispersal of taeniid eggs: Experimental faecal contamination of forest environment followed by DNA detection in wild berries.

To understand Taeniidae epidemiology, the principles of egg-dispersion dynamics under natural conditions must be known. In this study, non-zoonotic Taenia laticollis was used as a model parasite for the family Taeniidae (including Echinococcus spp.). An experiment to investigate dispersion from contaminated faeces to the surroundings was performed both with bilberries (Vaccinium myrtillus) and lingonberries (Vaccinium vitis-idaea), both of which are commercially harvested wild berries in Finland. For this experiment, 30 g of fox faeces was inoculated with 30,000 T. laticollis eggs for the bilberry experiment and 100,000 eggs for the lingonberry experiment. The faecal material was placed in the middle of good berry growth areas in four locations for bilberries and eight locations for lingonberries. After 41-42 days, berries at different distances (0-15 m) from the original contamination spot were collected and delivered to our laboratory. DNA was extracted from washed and sieved material and analysed using T. laticollis-specific semi-quantitative SYBR Green real-time polymerase chain reaction (qPCR). Taenia laticollis-specific DNA was recovered from 67% (8/12) of bilberry samples but not reliably from any of the lingonberry samples 0% (0/24), although the exposure dose was higher for those. The qPCR results suggest that under natural conditions, taeniid egg dispersion from the contamination spot is demonstrated but attachment is berry specific. The surface of bilberries may be more adhesive for taeniid eggs than the waxier and harder pericarp of the lingonberries or there might be a difference in the dispersal mechanism caused by different biotopes.

Carboxypeptidase A3 expression in canine mast cell tumors and tissue-resident mast cells.

Mast cell tumors (MCTs) are one of the most common cutaneous malignancies in dogs. Previous studies have reported expression of mast cell-specific proteases chymase and tryptase in canine cutaneous MCTs and in connective tissue and mucosal mast cells. In humans and rodents, mast cells express an additional specific protease, carboxypeptidase A3 (CPA3). In this article, we describe CPA3 immunoreactivity in connective tissue, visceral, mucosal, and neoplastic mast cells in dogs. Positive immunolabeling for CPA3 was observed in nonneoplastic mast cells in 20/20 formalin-fixed paraffin-embedded normal tissues (skin, liver, spleen, intestine), and in 63/63 MCTs irrespective of their histological grade. CPA3 protein expression was comparable to that of c-kit in both the nonneoplastic and neoplastic mast cells. Three distinct labeling patterns (membranous, diffuse, and focal cytoplasmic) were observed for CPA3 in MCTs. The focal cytoplasmic labeling pattern was associated with high-grade MCTs staged with the Kiupel 2-tier grading criteria. We propose CPA3 as a novel immunohistochemical marker for canine mast cells in health and disease.

Sarcocystis calchasi in a captive Patagonian conure (Cyanoliseus patagonus) in Finland.

Sarcosystis calchasi is an emerging pathogen causing encephalitis in many avian species and has been documented in North America, Germany and Japan. In November 2019, a captive Patagonian conure (Cyanoliseus patagonus), kept in a zoological aviary in Finland, was euthanized due to acute respiratory distress. At necropsy, histopathological examination revealed numerous parasitic tissue cysts in the skeletal muscles and myocardium, chronic moderate multifocal lymphoplasmacytic and histiocytic meningoencephalitis and acute moderate multifocal purulent pneumonia caused by aspiration of foreign material. By light and transmission electron microscopy, tissue cysts had structures typical of Sarcocystis organisms. The ultrastructure of the cyst wall was compatible with S. calchasi and Sarcocystis columbae. S. calchasi-specific semi-nested polymerase chain reaction testing resulted in amplification of the internal transcribed spacer (ITS) gene, which had 100% identity with S. calchasi ITS sequences. This is the first report of S. calchasi in Fennoscandia and of a naturally-occurring S. calchasi infection in a captive psittacine bird in Europe. Our finding suggests that captive psittacine birds kept in outdoor facilities may be at risk of S. calchasi infection throughout the Holarctic.

Severe deforming dermatitis in a kitten caused by Caryospora bigenetica.

BACKGROUND: Caryospora bigenetica is an intracellular protozoan parasite, which in its primary hosts, typically snakes, is found it the intestine. Extraintestinal multiplication with the development of tissue cysts takes place in secondary hosts, which are normally prey for snakes. Natural infection in domestic animals has been reported only in dogs; this is the first report of C. bigenetica infection in a cat. CASE PRESENTATION: A stray kitten developed nodular dermatitis after being adopted by a shelter. Firm swelling, nodules, and crusts were present mainly on the nasal bridge, eyelids, and pinnae. Histopathology and cytology revealed severe pyogranulomatous inflammation with abundant intracellular organisms suggestive of apicomplexan protozoa. Treatment with clindamycin 13 mg/kg twice daily was initiated, but the cat was euthanized because of the worsening condition. Transmission electron microscopy confirmed parasite's apicomplexan origin postmortem, and the causative agent was identified as C. bigenetica by polymerase chain reaction and DNA sequencing. CONCLUSIONS: We present the first case of a naturally occurring infection with C. bigenetica in a cat. Although the definitive etiological diagnosis relied on molecular identification, the abundance of unsporulated oocysts and caryocysts and the parasite's effective reproduction within macrophages and in several other cell types might have enabled differentiation from other protozoal infections and allowed a presumptive diagnosis through cytology and histopathology.

Severe Spontaneous Atherosclerosis in two Korat Breed Cats is Comparable to Human Atherosclerosis.

Atherosclerosis is a chronic inflammatory vascular disease and the leading cause of mortality in humans worldwide. In most domestic animal species, however, primary atherosclerosis is of little clinical relevance. Cats are considered to be atheroresistant and, to our knowledge, spontaneous atherosclerosis has not been reported in cats. Here we report the clinical and histopathological findings in two related cats of the Korat breed that presented with clinical signs of heart failure. In both cases, the clinical signs appeared in adulthood, were progressive and led to death. At necropsy, severe atherosclerotic lesions were present in large and medium-sized arteries and were characterized by the formation of a fibrous cap and a lipid core, which contained a particularly large accumulation of cholesterol crystals, as indicated by the presence of many cholesterol clefts. The lesions closely resembled those of advanced human atherosclerosis. There were no underlying diseases or medical treatments that could have predisposed to the atherosclerosis in these two genetically related cats. A genetic predisposition to human-like atherosclerosis in the local Korat cat population is suspected.

Cytokeratin 5 determines maturation of the mammary myoepithelium.

At invasion, transformed mammary epithelial cells expand into the stroma through a disrupted myoepithelial (ME) cell layer and basement membrane (BM). The intact ME cell layer has thus been suggested to act as a barrier against invasion. Here, we investigate the mechanisms behind the disruption of ME cell layer. We show that the expression of basal/ME proteins CK5, CK14, and α-SMA altered along increasing grade of malignancy, and their loss affected the maintenance of organotypic 3D mammary architecture. Furthermore, our data suggests that loss of CK5 prior to invasive stage causes decreased levels of Zinc finger protein SNAI2 (SLUG), a key regulator of the mammary epithelial cell lineage determination. Consequently, a differentiation bias toward luminal epithelial cell type was detected with loss of mature, α-SMA-expressing ME cells and reduced deposition of basement membrane protein laminin-5. Therefore, our data discloses the central role of CK5 in mammary epithelial differentiation and maintenance of normal ME layer.

Genomic insights into the host specific adaptation of the Pneumocystis genus.

Pneumocystis jirovecii, the fungal agent of human Pneumocystis pneumonia, is closely related to macaque Pneumocystis. Little is known about other Pneumocystis species in distantly related mammals, none of which are capable of establishing infection in humans. The molecular basis of host specificity in Pneumocystis remains unknown as experiments are limited due to an inability to culture any species in vitro. To explore Pneumocystis evolutionary adaptations, we have sequenced the genomes of species infecting macaques, rabbits, dogs and rats and compared them to available genomes of species infecting humans, mice and rats. Complete whole genome sequence data enables analysis and robust phylogeny, identification of important genetic features of the host adaptation, and estimation of speciation timing relative to the rise of their mammalian hosts. Our data reveals insights into the evolution of P. jirovecii, the sole member of the genus able to infect humans.

Altered Basal Autophagy Affects Extracellular Vesicle Release in Cells of Lagotto Romagnolo Dogs With a Variant ATG4D.

Lagotto Romagnolo breed dogs develop a progressive neurological disease with intracellular vacuolar storage when homozygous for a variant in the autophagy-related gene 4D (ATG4D). A lysosomal enzyme deficiency has not been proven in this disease, despite its overlapping morphology with lysosomal storage diseases. Instead, basal autophagy was altered in fibroblasts from affected dogs. The aim of this study was to clarify the origin of the limiting membrane of the accumulating vacuoles and determine whether altered basal autophagy affects the extracellular release of vesicles in cells from diseased dogs. When assessed by immunoelectron microscopy, the membrane of the cytoplasmic vacuoles in affected tissues contained ATG4D, markers for autolysosomes (microtubule-associated protein 1A/B light chain 3 and lysosome-associated membrane protein 2) and for recycling endosomes (transferrin receptor 2), indicating that the vacuoles are hybrid organelles between endocytic and autophagic pathways. Ultracentrifugation, nanoparticle tracking analysis, and mass spectrometry were used to analyze the vesicles released from cultured fibroblasts of affected and control dogs. The amount of extracellular vesicles (EVs) released from affected fibroblasts was significantly increased during basal conditions in comparison to controls. This difference disappeared during starvation. The basal EV proteome of affected cells was enriched with cytosolic, endoplasmic reticulum, and mitochondrial proteins. Heat shock proteins and chaperones, some of which are known substrates of basal autophagy, were identified among the proteins unique to EVs of affected cells. An increased release of extracellular vesicles may serve as a compensatory mechanism in disposal of intracellular proteins during dysfunctional basal autophagy in this spontaneous disease.

Antibodies Against Hepatitis E Virus (HEV) in European Moose and White-Tailed Deer in Finland.

The main animal reservoirs of zoonotic hepatitis E virus (HEV) are domestic pigs and wild boars, but HEV also infects cervids. In this study, we estimated the prevalence of HEV in Finnish cervid species that are commonly hunted for human consumption. We investigated sera from 342 European moose (Alces alces), 70 white-tailed deer (Odocoileus virginianus), and 12 European roe deer (Capreolus capreolus). The samples had been collected from legally hunted animals from different districts of Finland during 2008-2009. We analysed the samples for total anti-HEV antibodies using a double-sandwich ELISA assay. Seropositive sera were analysed with RT-qPCR for HEV RNA. HEV seroprevalence was 9.1% (31/342) in moose and 1.4% (1/70) in white-tailed deer. None of the European roe deer were HEV seropositive (0/12). No HEV RNA was detected from samples of seropositive animals. HEV seropositive moose were detected in all districts. Statistically, HEV seroprevalence in moose was significantly higher (p < 0.05) in the North-East area compared to the South-West area. The highest HEV seroprevalence (20.0%) in district level was more than six times higher than the lowest (3.1%). We demonstrated the presence of total anti-HEV antibodies in European moose and white-tailed deer in Finland. Our results suggest that HEV is circulating among the moose population. Infections may occur also in white-tailed deer. We were the first to report a HEV seropositive white-tailed deer from Europe. Further studies are needed to demonstrate the HEV genotypes in cervids in Finland and to evaluate the importance of the findings in relation to food safety.

Diversity and Complexity of the Large Surface Protein Family in the Compacted Genomes of Multiple Pneumocystis Species.

Pneumocystis, a major opportunistic pathogen in patients with a broad range of immunodeficiencies, contains abundant surface proteins encoded by a multicopy gene family, termed the major surface glycoprotein (Msg) gene superfamily. This superfamily has been identified in all Pneumocystis species characterized to date, highlighting its important role in Pneumocystis biology. In this report, through a comprehensive and in-depth characterization of 459 msg genes from 7 Pneumocystis species, we demonstrate, for the first time, the phylogeny and evolution of conserved domains in Msg proteins and provide a detailed description of the classification, unique characteristics, and phylogenetic relatedness of five Msg families. We further describe, for the first time, the relative expression levels of individual msg families in two rodent Pneumocystis species, the substantial variability of the msg repertoires in P. carinii from laboratory and wild rats, and the distinct features of the expression site for the classic msg genes in Pneumocystis from 8 mammalian host species. Our analysis suggests multiple functions for this superfamily rather than just conferring antigenic variation to allow immune evasion as previously believed. This study provides a rich source of information that lays the foundation for the continued experimental exploration of the functions of the Msg superfamily in Pneumocystis biology.IMPORTANCEPneumocystis continues to be a major cause of disease in humans with immunodeficiency, especially those with HIV/AIDS and organ transplants, and is being seen with increasing frequency worldwide in patients treated with immunodepleting monoclonal antibodies. Annual health care associated with Pneumocystis pneumonia costs ∼$475 million dollars in the United States alone. In addition to causing overt disease in immunodeficient individuals, Pneumocystis can cause subclinical infection or colonization in healthy individuals, which may play an important role in species preservation and disease transmission. Our work sheds new light on the diversity and complexity of the msg superfamily and strongly suggests that the versatility of this superfamily reflects multiple functions, including antigenic variation to allow immune evasion and optimal adaptation to host environmental conditions to promote efficient infection and transmission. These findings are essential to consider in developing new diagnostic and therapeutic strategies.

Risk factors for equine intestinal parasite infections and reduced efficacy of pyrantel embonate against Parascaris sp.

Gastrointestinal parasites, Parascaris sp. and strongyles, are common in young horses worldwide and control of these parasites is challenged by increasing anthelmintic resistance. Our aim was to identify risk factors for these infections as well as to assess the efficacy of fenbendazole (dose 7.5 mg/kg) and pyrantel embonate (dose 19 mg/kg) against Parascaris sp. We also evaluated association between owner observed symptoms and patent infections with these parasites. Fecal samples were collected from 367 young horses in Finland and a questionnaire study was conducted. Fecal egg counts were performed by Mini-FLOTAC® method. Univariable logistic regression models using patent infection status (Yes/No), separately for Parascaris sp. and strongyle infections as an outcome were run initially to screen potential risk factors collected by the questionnaire. After the initial screening, multiple logistic regression models were constructed and run to account for correlated data structure, risk factors and potential confounders simultaneously. Two significant risk factors for a patent Parascaris sp. infection were found: breeding farm size (p = 0.028) and frequency of horse movements (p = 0.010). Horses originating from large breeding farms were more likely (OR = 2.47, 95% confidence interval (CI) 1.10-5.51) to shed Parascaris sp. eggs upon relocation to training stables compared to horses originating from small breeding farms. Horses living in farms with frequent horse movements to other premises had higher odds (OR = 3.56, 95% CI: 1.35-9.39) of a patent Parascaris sp. infection compared to farms with less frequent horse movements. Risk factors for patent strongyle infection included age (p < 0.001) and season (p = 0.017). Horses were less likely (OR = 0.27, 95% CI: 0.10 - 0.66) to shed strongylid eggs during the spring compared to the winter. Horses excreting over 200 ascarid eggs per gram were included in the anthelmintic efficacy trial. A mean FECR less than 90% was interpreted as presence of anthelmintic resistance. The mean FECR was 98.5% (95% CI: 95.8-100) and 68.0% (95% CI: 52.7-83.3) in the fenbendazole (n = 31) and pyrantel (n = 26) treatment groups, respectively. In conclusion, we identified two new risk factors for patent Parascaris sp. infection; breeding farm size and frequency of horse movements. Reduced efficacy of pyrantel against Parascaris sp. was observed for the second time in Europe. A relatively high Parascaris sp. prevalence in yearlings (34%) and two-year-olds (20%) was observed, which has not been reported earlier. An association between symptoms and a patent Parascaris sp. infection was observed in foals.

Berries as a potential transmission vehicle for taeniid eggs.

Potential role of wild forest berries as a transmission vehicle for taeniid eggs was examined using non-zoonotic Taenia laticollis eggs as a model. The berries studied were bilberries (Vaccinium myrtillus) (1 m2 plot, n = 10) and lingonberries (Vaccinium vitis-idaea) (1 m2 plot, n = 11). The plots in the managed forest were evenly sprayed with 30,000 or 60,000 T. laticollis eggs suspended in water, and berries were collected 24 h after spraying. The berries were rinsed with water, and the water was sieved through a 1-mm and a 63-µm sieve to remove coarse material and through a 20-µm sieve to collect possible eggs. A small proportion of the sieved material was examined by microscopy after treatment with fluorescent Calcofluor White stain, which binds to eggshell chitin. In the recovery tests in artificially spiked samples, the detection limit was 5 eggs in 100 g of commercial frozen bilberries and lingonberries. Taeniid eggs were detected in all of the 10 experimentally contaminated bilberry samples and in 10 of 11 lingonberry samples. The sieved debris was also analyzed for T. laticollis DNA using semi-quantitative PCR. All samples were positive in quantitative SYBR Green real-time PCR using a T. laticollis-specific primer pair amplifying a short fragment of mitochondrial NADH dehydrogenase subunit 1 gene. This indicates that forest berries contaminated in shrubs contained T. laticollis eggs, and that berries can serve as a vehicle for taeniid eggs and may pose a possible risk to humans.

A new SYBR green real-time PCR assay for semi-quantitative detection of Echinococcus multilocularis and Echinococcus canadensis DNA on bilberries (Vaccinium myrtillus).

Berries and vegetables are potential transmission vehicles for eggs of pathogenic parasites, such as Echinococcus spp. We developed a SYBR Green based semi-quantitative real-time PCR (qPCR) method for detection of Echinococcus multilocularis and Echinococcus canadensis DNA from berry samples. A set of primers based on the mitochondrial NADH dehydrogenase subunit 1 (nad1) gene was designed and evaluated. To assess the efficacy of the assay, we spiked bilberries (Vaccinium myrtillus) with a known amount of E. multilocularis eggs. The detection limit for the assay using the NAD1_88 primer set was 4.37 × 10-5 ng/µl of E. multilocularis DNA. Under artificial contamination of berries, 50 E. multilocularis eggs were reliably detected in 250 g of bilberries. Analytical sensitivity of the assay was determined to be 100% with three eggs. As an application of the assay, 21 bilberry samples from Finnish market places and 21 bilberry samples from Estonia were examined. Previously described sieving and DNA extraction methods were used, and the samples were analyzed for E. multilocularis and E. canadensis DNA using semi-quantitative real-time PCR and a melting curve analysis of the amplified products. Echinococcus DNA was not detected in any of the commercial berry samples. This easy and fast method can be used for an efficient detection of E. multilocularis and E. canadensis in bilberries or other berries, and it is applicable also for fruits and vegetables.

Acute fulminant necrotizing myopathy in a dog caused by co-infection with ultrastructural Sarcocystis caninum and Sarcocystis svanai-like apicomplexan protozoa.

Typically, carnivores are the definitive and herbivores the intermediate hosts for protozoan Sarcocystis spp. In the definitive host, the parasite has sexual multiplication in the intestine. Asexual phases occur in the musculature of different intermediate hosts. Although intestinal sarcocystosis is common in dogs, muscular symptomatic sarcocystosis is rarely reported. Here we report a fatal dual Sarcocystis spp. infection in a dog. The dog had acute onset of non-ambulatory tetraparesis. While neurological findings suggested a generalized neuromuscular disease with peripheral neuropathy concordant with the neurological deficits, the highly elevated muscle enzymes were more suggestive of a myopathy. Despite supportive therapy, the dog died three days after the onset of clinical signs. Necropsy revealed severe monophasic multifocal myodegeneration with severe pyogranulomatous inflammation. Histology revealed multiple sarcocysts in skeletal muscles and a smaller number in the heart. In light microscopy, both thin-walled and very thin-walled sarcocysts were found in skeletal muscles. Transmission electron microscopy confirmed the presence of two types of mature sarcocysts. Morphologically, cysts were indistinguishable from Sarcocystis caninum and Sarcocystis svanai, which were previously reported in a dog from USA. A region of the 18S rRNA gene sequence confirmed the presence of one species, S. arctica/caninum, without evidence for a dual infection. This is the first report of muscular sarcocystosis in a dog in Europe and, intriguingly, revealed morphologically similar species across the Atlantic.

Surveillance and diagnosis of zoonotic foodborne parasites.

Foodborne parasites are a source of human parasitic infection. Zoonotic infections of humans arise from a variety of domestic and wild animals, including sheep, goats, cattle, camels, horses, pigs, boars, bears, felines, canids, amphibians, reptiles, poultry, and aquatic animals such as fishes and shrimp. Therefore, the implementation of efficient, accessible, and controllable inspection policies for livestock, fisheries, slaughterhouses, and meat processing and packaging companies is highly recommended. In addition, more attention should be paid to the education of auditors from the quality control (QC) and assurance sectors, livestock breeders, the fishery sector, and meat inspection veterinarians in developing countries with high incidence of zoonotic parasitic infections. Furthermore, both the diagnosis of zoonotic parasitic infections by inexpensive, accessible, and reliable identification methods and the organization of effective control systems with sufficient supervision of product quality are other areas to which more attention should be paid. In this review, we present some examples of successful inspection policies and recent updates on present conventional, serologic, and molecular diagnostic methods for zoonotic foodborne parasites from both human infection and animal-derived foods.