Biology of Isospora spp. from humans, nonhuman primates, and domestic animals

Gastrointestinal parasites of cats in the Middle East (2000-2023): A literature review

BACKGROUND/OBJECTIVE

Gastrointestinal parasites in stray cats are of significant clinical and zoonotic importance and pose a potential threat to public health. Hence, the current review has practical implications as it aims to present the diversity and the prevalence of cat parasites in Middle Eastern countries.

METHODS

The research process was rigorous and thorough, spanning from 2000 to 2023. Data collection and analysis were conducted utilizing multiple international and national databases, including Google Scholar, Scopus, PubMed, and Irandoc. This meticulous approach ensures the reliability and validity of the findings, providing a solid foundation for further research and preventive measures.

RESULTS

A total of 159 articles were collected and comprehensively reviewed. Among these, 85 articles were from Iran, 25 from Türkiye, 20 from Iraq, 11 from Egypt, five from Qatar, three from Cyprus, three from Kuwait, and one each from the UAE, Saudi Arabia, Syria, Lebanon, Jordan, Israel, and Palestine. Toxocara cati was the most prevalent nematode, exhibiting the highest prevalence in Iran, ranging from 8% to 90%, followed by Egypt, with a range of 8.23% to 58.7%. In comparison, the lowest prevalence was recorded in Qatar at 8%. Hydatigera taeniaeformis, a common cestode in the feline, showed the highest prevalence in Qatar, with a range of 73.6% to 75.8%, while the lowest was in Kuwait at 0.8%. In Iran, the prevalence ranged from 0.9% to 64.7%. Toxoplasma gondii, a cosmopolitan protozoan, showcased the highest prevalence in Lebanon at 78.1% and the lowest in the UAE at 0.8%. In Iran, the prevalence ranged between 1.2% and 90%. Additionally, noteworthy patterns regarding the distribution and potential risk factors associated with these parasites were observed. While gender variations were not significant, environmental conditions such as high humidity and absence of sunlight exposure, along with the age and behavior of cats, were among the risk factors associated with the prevalence of parasites.

CONCLUSION

The prevalence of parasites among stray cats in Iran and other Middle Eastern countries remains notably high. This emphasizes the urgent need for a series of control and preventive measures. Implementing effective anti-parasitic strategies and emphasizing the development of multiple diagnostic methods are essential.

Sources and Prevalence of Cyclospora cayetanensis in Southeastern U.S. Growing Environments

Recent cyclosporiasis outbreaks associated with fresh produce grown in the United States highlight the need to better understand Cyclospora cayetanensis prevalence in U.S. agricultural environments. In this study, C. cayetanensis occurrence was assessed in municipal wastewater sludge, on-farm portable toilets, irrigation pond water, and spent packing house dump tank water in a Southeastern Georgia growing region over two years. Detection of the C. cayetanensis 18S rRNA qPCR gene target in pond samples was 0%, 28%, and 42% (N = 217) depending on the detection definition used, and ≤1% in dump tank samples (N = 46). However, no qPCR detections were confirmed by sequencing, suggesting false detection occurred due to cross-reactions. C. cayetanensis qPCR detections were confirmed in 9% of wastewater sludge samples (N = 76). The human-specific fecal markers HF183 and crAssphage were detected in 33% and 6% of pond samples, respectively, and 4% and 0% of dump tank samples, respectively. Despite community Cyclospora shedding and evidence of human fecal contamination in irrigation water, there was no correlation between C. cayetanensis and HF183 qPCR detections, further supporting that 18S gene target qPCR amplifications were due to cross-reactions. When evaluating C. cayetanensis qPCR environmental detection data, the impact of assay specificity and detection criteria should be considered. Moreover, additional sequence-based testing may be needed to appropriately interpret Cyclospora qPCR environmental data.

The effect of an injectable toltrazuril - gleptoferron (Forceris®) on Cystoisospora suis oocyst excretion and growth of neonatal piglets pre- and post-weaning

In this study the efficacy of an intramuscular formulation of toltrazuril combined with gleptoferron for the control of porcine cystoisosporosis caused by Cystoisospora suis was investigated. The study was carried out on three Belgian farms with a confirmed history of C. suis infections. As none of the farms implemented a standardized toltrazuril treatment regimen for their piglets, the presence of resistant C. suis strains seems improbable. In total 90 litters, representing 1249 piglets, were included in the study and randomly allocated to either the treatment or control group. Piglets in the treatment group received a single intramuscular injection, containing 45 mg toltrazuril and 200 mg gleptoferron, between 1 and 3 days of age. Piglets in the control group received a single injection with only 200 mg gleptoferron. The effect of treatment on oocyst excretion, expressed in oocysts per gram of feces (OPG), average daily weight gain (ADG) and mortality was determined both pre- and post-weaning. A significant decrease in OPG as well as a decrease in the number of litters (pre-weaning) and pens (post-weaning) that tested positive for cystoisosporosis, was observed in the treated animals compared to the controls. Furthermore, treatment resulted in an increased ADG during the period from day 1 to day 21 (p-value: 0.03881). There was no significant difference in mortality observed between the treatment group to the control group (p-value: 0.2167). To our knowledge, this is the first report on the effect of toltrazuril on oocyst excretion after weaning. This finding highlights the potential long-term benefits of the treatment beyond the initial administration.

On the efficacy of preventive toltrazuril treatments and the diagnosis of Cystoisospora suis infections in intensively raised piglets in farms from southeast Spain

This study investigated the presence and abundance of Cystoisospora suis oocysts in faecal samples from 131 one- to three-week-old pig litters belonging to eight intensively raised, indoor herds in Spain. Seven herds used preventive anticoccidial toltrazuril treatments administered orally or by intramuscular injection, and one did not use preventive anticoccidial treatments. The diagnosis was performed using two oocyst flotation-concentration methods, Bailenger's method in every herd and the more recent Joachim's method in four herds. Oocysts were detected in every farm, the proportion of oocyst-positive samples was higher with Bailenger's technique, and the estimated overall prevalence (95% confidence interval) was 40 (32-49)%, including 47 (29-65)% in non-medicated litters, 52 (38-67)% in orally medicated litters and 28 (16-40)% in intramuscularly medicated litters (p < 0.05). However, mixed logistic regression models indicated that the risk of infection was not significantly associated with preventive anticoccidial treatments (p > 0.05), and increased with age, was higher in herds with partially compared to fully slatted dung floors in farrowing pens and in litters with pigs with diarrhoea (p < 0.05). The median (range) oocysts per gram of faeces (OpG) in infected litters by Bailenger's method was 623 (35-49048) and mixed negative binomial models revealed no significant association between infection intensity in positive litters and pen's floor type and piglets age, faecal consistency and treatment status (p > 0.05). The apparent low efficacy of Toltrazuril suggests treatment administration failures, reduced residual efficacy or low susceptibility of C. suis strains in study farms and needs further investigation.

The detection and phylogenetic characterization of Cryptosporidium, Cystoisospora, and Giardia duodenalis of cats in South Korea

Introduction

Cryptosporidium, Cystoisospora, and Giardia duodenalis are gastrointestinal protozoa parasites that cause diarrhea in various animals. However, information regarding the detection and phylogenetic characterization of gastrointestinal protozoa parasites in cats is limited throughout South Korea. Therefore, this study aimed to determine the detection and identify subspecies of gastrointestinal protozoa parasites in cats from South Korea.

Methods

A total of 290 fecal samples were collected from stray, companion, and shelter cats in six provinces. Cryptosporidium, Cystoisospora, and G. duodenalis were identified by PCR. All positive samples were subtyped by PCR and sequencing of gp60, ITS-1, tpi, bg, and gdh.

Results

The overall detection of gastrointestinal protozoan parasitic infection was 17.93%. G. duodenalis was the most prevalent, with 7.93%, followed by Cystoisospora spp. (7.24%) and Cryptosporidium spp. (4.48%). In addition, C. felis (n=10), C. parvum (n=2), C. ryanae (n=1), Cystoisospora felis (n=14), Cystoisospora suis (n=5), Cystoisospora ohioensis (n=1), Cystoisospora spp. were identified in subspecies analysis of positive samples. C. felis showed a significant association with diarrhea (7.81%) and living condition (6.04%), and Cystoisospora felis in diarreha (9.38%) according to detection. Through phylogenetic analysis of the tpi, bg, and gdh genes from 23 G. duodenalispositive samples, it was confirmed that the samples of present study belonged to assemblage A, B, C, and D.

Discussion

South Korean cats have a high rate of gastrointestinal protozoan parasites infection with cat-specific Cryptosporidium and Cystoisospora, which are associated with living conditions and diarrhea symptoms. Moreover, zoonotic and other animal-specific subtype of protozoan parasites have been detected in cat feces.

The transcriptome from asexual to sexual in vitro development of Cystoisospora suis (Apicomplexa: Coccidia)

The apicomplexan parasite Cystoisospora suis is an enteropathogen of suckling piglets with woldwide distribution. As with all coccidian parasites, its lifecycle is characterized by asexual multiplication followed by sexual development with two morphologically distinct cell types that presumably fuse to form a zygote from which the oocyst arises. However, knowledge of the sexual development of C. suis is still limited. To complement previous in vitro studies, we analysed transcriptional profiles at three different time points of development (corresponding to asexual, immature and mature sexual stages) in vitro via RNASeq. Overall, transcription of genes encoding proteins with important roles in gametes biology, oocyst wall biosynthesis, DNA replication and axonema formation as well as proteins with important roles in merozoite biology was identified. A homologue of an oocyst wall tyrosine rich protein of Toxoplasma gondii was expressed in macrogametes and oocysts of C. suis. We evaluated inhibition of sexual development in a host-free culture for C. suis by antiserum specific to this protein to evaluate whether it could be exploited as a candidate for control strategies against C. suis. Based on these data, targets can be defined for future strategies to interrupt parasite transmission during sexual development.

The strong influence of management factors on coccidian infections in smallholder pig farms and the first molecular identification of Cystoisospora suis in Myanmar

A cross-sectional study was conducted to investigate coccidian infection and associated factors in smallholder pigs, and to identify Cystoisospora oocysts by PCR. A total of 500 pig faecal samples from 330 smallholder farms were collected in Nay Pyi Taw, Myanmar. The faecal flotation method was used to identify Eimeria and Cystoisospora species, and oocyst counts per gram (OPG) of faeces were recorded. Oocysts were differentiated after sporulation. Oocyst DNA was subjected to ITS1-targeted Cystoisospora-specific PCR. The overall coccidian oocyst detection rate by microscopic was 89.0% (445/500). Among the studied samples, 74.0% (370/500) and 70.6% (353/500), were found to be positive with Eimeria spp. and Cystoisospora suis oocysts, respectively. The sequences of C. suis detected were 100% identical to those of C. suis reported from Japan, and had 99.5% resemblance to sequences from Australia and China. Weaner pigs showed the significantly highest (p < 0.05) OPG when compared to other age groups. The highest intensity of coccidian infection (p < 0.05) was found in pigs fed local feed, pigs raised on earthen floors and pigs under poor hygienic conditions. Factors such as age, breed, feed type, and housing floors were found to be significantly associated with coccidian infection (p < 0.05). Age, as well as management factors including floor type, feed type, and hygiene practices on the farm, had a strong influence on the occurrence of coccidian infection in pigs. This is the first study in Myanmar on coccidian infection in pigs and molecular detection of C. suis.

Cystoisospora belli, liver disease and hypothesis on the life cycle

Cystoisospora belli causes chronic diarrhoea, acalculous cholecystitis, cholangiopathy and disseminated cystoisosporosis in patients with AIDS. Clinical manifestations and histological stages during C. belli infection in a patient with AIDS and liver disease were described. It was possible to identify sporozoite-like structures in the villus epithelium of the duodenum, close to the vascularization that underlies the basal membrane and unizoite tissue cysts near to the vascularization in the lamina propria. Unizoite tissue cysts were found inside of sinusoids in the liver communicating with the central vein and with a bile canaliculus and portal spaces. Based on these findings a hypothesis on C. belli life cycle could consider that the route of migration of unizoite tissue cysts up the liver is via the portal blood. The unizoite tissue cysts located in hepatic portal vein could migrated via sinusoid to central vein and general circulation through the venous system. The unizoite tissue cysts could also return via bile canaliculus to bile duct to portal triad. This hypothesis allows to understand the presence of unizoite stages in blood, the pathway by which the bile ducts become infected and unizoites in the liver being able to behave like hypnozoites that favour relapses and treatment failures.

Detection and molecular characterisation of intestinal parasites in the South China tiger Panthera tigris amoyensis (Hilzheimer)

Parasitic infections of the South China tigers in the Meihua Mountains have not been explored previously. Faeces of 22 South China tigers from the China Tiger Park in the Meihua Mountains were examined. Eggs of ascaridoid nematodes and oocysts of coccidia were detected by Mini-FLOTAC assay. Morphological observation and molecular characterisation of the oocysts were carried out. The prevalence of Toxascaris leonina (von Linstow, 1902) was 18% (4/22), and the highest egg per gram (EPG) count in the faeces was 27,150. The prevalence of Cystoisospora sp. was 45% (1 0/22) and the highest oocysts per gram (OPG) in the faeces was 6,000. In addition, we found one ascaridoid nematode in the South China tiger's faeces and was molecularly and morphologically identified as T. leonina. The oocysts in the faeces were sporulated in vitro and identified as Cystoisospora sp. Amplification of full-length internal transcribed spacers (ITS) resulted in sequences 1,622 bp long. Using the sequences, Cystoisospora sp. of the South China tiger was closest to Isospora belli (Wenyon, 1923) and Cystoisospora suis (Biester, 1934).

Cystoisospora belli infection in an AIDS patient in China: Need for cautious interpretation of mNGS

Cystoisospora belli (C. belli) is an opportunistic coccidian parasite. This case is the first reported C. belli infection associated with AIDS in China. C. belli infection of this case was diagnosed with the presence of oocysts using direct wet mount and Ziehl-Neelsen acid-fast stain method, and confirmed by polymerase chain reaction (PCR) and Sanger sequencing, ruling out the result of metagenomic next-generation sequencing (mNGS). This case demonstrates that C. belli infection in AIDS could be a potential risk factor for persistent diarrhea, and should not be neglected in non-endemic area and emphaise the necessity of accurate mNGS databases.

From celiac disease to coccidia infection and vice-versa: The polyQ peptide CXCR3-interaction axis

Zonulin is a physiological modulator of intercellular tight junctions, which upregulation is involved in several diseases like celiac disease (CeD). The polyQ gliadin fragment binds to the CXCR3 chemokine receptor that activates zonulin upregulation, leading to increased intestinal permeability in humans. Here, we report a general hypothesis based on the structural connection between the polyQ sequence of the immunogenic CeD protein, gliadin, and enteric coccidian parasites proteins. Firstly, a novel interaction pathway between the parasites and the host is described based on the structural similarities between polyQ gliadin fragments and the parasite proteins. Secondly, a potential connection between coccidial infections as a novel environmental trigger of CeD is hypothesized. Therefore, this report represents a promising breakthrough for coccidian research and points out the potential role of coccidian parasites as a novel trigger of CeD that might define a preventive strategy for gluten-related disorders in general. Also see the video abstract here: https://youtu.be/oMaQasStcFI.

A survey of intestinal helminths in domestic dogs in a human-animal-environmental interface: the Oloisukut Conservancy, Narok County, Kenya

Dogs living in a domestic-wildlife interface can serve as reservoirs and sentinels of parasites shared among humans, domestic animals and wildlife. In Kenya, the epidemiology of intestinal parasites of dogs and their role as reservoirs of zoonoses is poorly understood, especially in domestic-wildlife interfaces. This study aimed to determine the occurrence of intestinal helminths in domestic dogs in the Oloisukut Conservancy. One hundred dog faecal samples were collected per rectum and examined microscopically following zinc chloride flotation and formal-ether concentration techniques. Genotyping of helminths was achieved by nested polymerase chain reaction of NADH dehydrogenase subunit 1, cytochrome oxidase 1 and partial sequencing. Nine genera were detected by microscopy in 65 (65%) dog faecal samples from 54/76 (71.05%) households. The most frequent helminths were hookworm (39%), Spirometra spp. (17%), taeniids (13%), Toxocara spp. (10%), Trichuris spp. (10%), Spirocerca lupi (5%), Physaloptera spp. (2%), Dipylidium caninum (1%) and Strongyloides spp. (1%). Ancylostoma caninum was the only hookworm species detected in dogs, while Taenia serialis and Taenia madoquae were detected in four and one faecal samples, respectively. This study reports for the first time the molecular detection of the cestodes Spirometra theileri, D. caninum and Mesocestoides sp. in dogs in Kenya. The presence of zoonotic helminths in dogs indicates that the residents of this conservancy are exposed to public health risks. The helminths reported here confirm the interaction of domestic dogs with wildlife. An integrated control programme involving the medical, veterinary and wildlife conservation professionals is needed to avert transmission of infectious diseases to humans, domestic animals and wildlife.

Influence of extraordinary floods on wildlife parasites: the case of gastrointestinal helminths and protozoa of wild canids from the Iberá Ecoregion, Argentina

Parasites are natural components of ecosystems and play a significant role in the dynamics of wild animal populations. Although the environment of parasites is primarily defined by the host, most life cycles involve stages that must endure external conditions. Rainfall and flooding events are important factors that might influence the transport of parasitic stages, altering soil moisture levels, and resulting in a favorable environment for parasite survival and development. We assessed whether an extraordinary flood event modified the occurrence of gastrointestinal parasites (nematodes and protozoa) in wild canids in two protected areas in northern Argentina. From 2016 to 2018, we collected fecal samples of two fox species, Lycalopex gymnocercus and Cerdocyon thous, and examined the presence of nematodes and protozoa. We assessed changes in the occurrence of these parasites after a flood event, while adjusting for potential confounders (i.e., monthly average temperature, season, host species, site). In a second stage of the analysis, we evaluated whether part of the effect was caused by changes in soil moisture, by adding normalized difference water index as an independent variable. We found that the presence of nematodes in foxes was higher after flooding than before flooding, and this association was not explained by changes in the soil moisture. On the other hand, the flood event was not relevant for protozoa. Stronger and long-lasting flood events are expected due to the effect of global warming on El Niño events, and this may increase and intensify the spread of some parasites affecting wildlife, which could also be of public health concern.

Research Relevant Background Lesions and Conditions: Ferrets, Dogs, Swine, Sheep, and Goats

Animal models provide a valuable tool and resource for biomedical researchers as they investigate biological processes, disease pathogenesis, novel therapies, and toxicologic studies. Interpretation of animal model data requires knowledge not only of the processes/diseases being studied but also awareness of spontaneous conditions and background lesions in the model that can influence or even confound the study results. Species, breed/stock, sex, age, anatomy, physiology, diseases (noninfectious and infectious), and neoplastic processes are model features that can impact the results as well as study interpretation. Here, we review these features in several common laboratory animal species, including ferret, dog (beagle), pig, sheep, and goats.

Aptamer-based approaches for the detection of waterborne pathogens

Waterborne ailments pose a serious threat to public health and are a huge economic burden. Lack of hygiene in drinking and recreational water is the chief source of microbial pathogens in developing countries. Poor water quality and sanitation account for more than 3.4 million deaths a year worldwide. This has urged authorities and researchers to explore different avenues of pathogen detection. There is a growing demand for rapid and reliable sensor technologies, in particular those that can detect in situ and perform in harsh conditions. Some of the major waterborne pathogens include Vibrio cholerae, Leptospira interrogans, Campylobacter jejuni, Shigella spp., enterotoxigenic Escherichia coli, Clostridium difficile, Cryptosporidium parvum, Entamoeba histolytica, and Hepatitis A virus. While conventional methods of pathogen detection like serodiagnosis and microbiological methods have been superseded by nucleic acid amplification methods, there is still potential for improvement. This review provides an insight into aptamers and their utility in the form of aptasensors. It discusses how aptamer-based approaches have emerged as a novel strategy and its advantages over more resource-intensive and complex biochemical approaches.

Pitfalls in Morphologic Diagnosis of Pathogens: Lessons Learned From the Pseudo-Cystoisospora Epidemic

Multiple groups have recently reported involvement of the gallbladder mucosa of immunocompetent patients by cystoisospora organisms. However, this has recently been disproved with the support of molecular and ultrastructural studies. Here we present a summary of these events, recounting how this pseudo-Cystoisospora epidemic began and ended. This review also highlights the important role played by ancillary techniques in supplementing the morphologic diagnosis of pathogens.

Non-invasive sampling in Itatiaia National Park, Brazil: wild mammal parasite detection

Background

Non-invasive sampling through faecal collection is one of the most cost-effective alternatives for monitoring of free-living wild mammals, as it provides information on animal taxonomy as well as the dynamics of the gastrointestinal parasites that potentially infect these animals. In this context, this study aimed to perform an epidemiological survey of gastrointestinal parasites using non-invasive faecal samples from carnivores and artiodactyls identified by stool macroscopy, guard hair morphology and DNA sequencing in Itatiaia National Park. Between 2017 and 2018, faeces from carnivores and artiodactyls were collected along trails in the park. The host species were identified through macroscopic and trichological examinations and molecular biology. To investigate the parasites, the Faust, Lutz and modified Ritchie and Sheather techniques and enzyme immunoassays to detect Cryptosporidium sp. antigens were used.

Results

A total of 244 stool samples were collected. The species identified were Chrysocyon brachyurus, Leopardus guttulus, Canis familiaris, Cerdocyon thous, Puma yagouaroundi, Leopardus pardalis, Puma concolor and Sus scrofa. There were 81.1% samples that were positive for parasites distributed mainly in the high part of the park. Helminths, especially eggs of the family Ascarididae, were more frequently detected in carnivore faeces (70.9%). Protozoa, especially Cryptosporidium sp., represented the highest frequency of infection in artiodactyl faeces (87.1%). This zoonotic protozoon was detected in eight mammalian species, including in a wild boar. High values of structural richness and Shannon and Simpson diversity indices were observed for the parasites, especially in the faeces of C. brachyurus. Significant differences in parasite diversity were observed between wild and domestic animals, such as C. brachyurus and C. familiaris, respectively, and between taxonomically distant species, such as C. brachyurus and S. scrofa. The highest values for parasite similarity were found among the species that frequented similar areas of the park, such as C. brachyurus and L. guttulus.

Conclusions

The animals and parasite infections were identified through the combination of three techniques. High frequency parasite structures were diagnosed. Zoonotic protozoa were found and mainly occurred in samples from introduced species.

Environmental DNA from plastic and textile marine litter detects exotic and nuisance species nearby ports

Marine debris is currently a significant source of environmental and economic problems. Floating litter can be employed by marine organisms as a surface to attach to and use as spreading vector. Human activities are promoting the expansion of potentially harmful species into novel ecosystems, endangering autochthonous communities. In this project, more than 1,000 litter items were collected and classified from five beaches eastwards the port of Gijon, in Asturias, Spain. Next generation sequencing was employed to study biofouling communities attached to items of different materials. A dominance of DNA from Florideophyceae, Dinophyceae and Arthropoda was found, and four non-indigenous species (NIS) were identified. Results showed a clear preference of Florideophyceae and Bryozoa to attach on textile surfaces versus plastic ones. Considering that these taxa contain several highly invasive species described to date, these data emphasize the potential of textile marine debris as a vector for dispersal of NIS. Moreover, the closest beaches to the port contained a more similar biota profile than the farther ones, confirming that both plastic and textile marine litter can be vectors for species dispersal from ports.

Gastrointestinal parasites in the opossum Didelphis aurita: Are they a potential threat to human health?

Currently, a great proportion of the emerging infectious human diseases are zoonotic, with most of the pathogens originated from wildlife. In this sense, synanthropic animals such as marsupials play important role in the dissemination of pathogens due to their proximity to human dwellings. These hosts are affected by many gastrointestinal parasites, including species with zoonotic potential. The aim of this study was to assess the diversity of gastrointestinal parasites infecting the black-eared opossum D. aurita captured in urban areas of Southeastern, Brazil. In addition, the potential risk for the human population based on the One Health perspective has been discussed. Forty-nine marsupial specimens were captured with Tomahawk live traps and fecal samples were collected. The samples were evaluated by parasitological procedures. Eggs and oocysts were analyzed at different magnifications (400 × and 1000 ×), and their identification, together with adult nematodes, was established on morphological and morphometric data. Forty-three hosts (87.76%) scored positive for at least one gastrointestinal parasite, being 83.67% (41/49) for helminths, and 65.30% (32/49) for protozoa. For Cryptosporidium sp., only 13 samples were evaluated due to insufficient amount of feces obtained of some animals. A prevalence of 23.08% (3/13) was reported for this parasite. PCR analysis revealed Ancylostomatidae eggs to belong to the genus Ancylostoma. Our results demonstrated that multiparasitism is frequently found in these animals and a high percentage of potentially zoonotic parasites are observed, implying that D. aurita may be involved in zoonotic cycles in urban environments.

Investigation of systemic isosporosis outbreaks in an aviary of greenfinch (Carduelis chloris) and goldfinch (Carduelis carduelis) and a possible link with local wild sparrows (Passer domesticus)

CASE REPORT

An outbreak of systemic isosporosis caused mortalities in greenfinches (Carduelis chloris) and goldfinches (Carduelis carduelis) kept in an aviary in the western suburbs of Melbourne. The following year, a further outbreak in the same aviary occurred in a different flock of goldfinches. At the time of the second outbreak, dead and sick common sparrows (Passer domesticus) discovered near the aviary were also found to have systemic isosporosis.

METHOD

The systemic isosporosis was investigated and described using histopathology, electron microscopy and sequence analysis of the 18s gene.

RESULTS

Isospora spp. infecting the greenfinch and the goldfinch caused significant thickening of the duodenal lamina propria. Measurements in the goldfinches showed an inverse correlation coefficient between the thickening of the duodenum and the weightof the birds. Electron microscopy confirmed the presence of Isospora spp. within lymphocytes migrating into the lamina propria of the duodenum. Analysis of the 18s sequence discovered two different gene sequences across the three species of birds that didn't completely match any sequences previously deposited in GenBank.

CONCLUSION

Although the sparrows were found to have died from causes other than systemic Isospora, molecular studies of samples from their liver revealed the presence of an Isospora with 18s gene sequence identical to that found in the captive greenfinches.

Shifts in the Fecal Microbial Community of Cystoisospora suis Infected Piglets in Response to Toltrazuril

The protozoan parasite Cystoisospora suis causes diarrhea and reduced weight gain in suckling piglets. Infections occur in the first days of life; it is transient but can lead to dysbiosis, exacerbating disease and increasing mortality. Cystoisosporosis is effectively controlled by toltrazuril treatment; however, alterations of the gut microbial composition upon infection and treatment have not been investigated. This study evaluated the development of fecal microbiota of C. suis infected piglets in response to treatment with toltrazuril. Thirty-eight conventional piglets were infected with C. suis on the first day of life (dol 1). Twenty-six of them received either parenteral or oral toltrazuril 2 days later. Fecal samples were collected pre- and post-weaning (dol 1-15 and 31-38) for microbiota analysis using 16S rRNA amplicon sequencing and during dol 5-18 to determine fecal consistency and parasite excretion. All control animals shed parasites at least once and the majority developed diarrhea, while toltrazuril-treated piglets did not excrete parasites and only had low levels of diarrhea. Age-related shifts in the fecal microbiota composition and increase in diversity and species richness were seen until after weaning. Parasite infection disrupted bacterial maturation 2 weeks after infection. Irrespective of the route of administration, fecal communities of piglets in the treated groups clustered separately and were more diverse compared to that of control piglets during the acute phase of infection on dol 11. Control piglet feces showed higher levels of Fusobacteriaceae and Veillonellaceae, while Ruminococcaceae, Lachnospiraceae, S24-7, Clostridiaceae, and Erysipelotrichaceae were more abundant in feces of treated piglets on dol 11. Thereafter, treatment-related effects on the microbial communities were small and mainly detectable on dol 34 (5 days post-weaning), potentially indicating that the oral toltrazuril treatment might have had long-term effects on host physiological responses post-weaning. Irrespective of the administration route, toltrazuril prevented C. suis-related dysbiosis and maintained species richness and diversity on dol 11. In addition to cystoisosporosis prevention, toltrazuril seems to contribute to the stabilization of the gut microbial development during the suckling phase and thus may reduce the need for antibiotics to control infections with secondary bacterial enteropathogens in C. suis-infected suckling piglets.

Resurrection of the genus Eumonospora (Apicomplexa: Sarcocystidae) for Caryospora species without Stieda body

The coccidian genus Eumonospora Allen, 1933 is re-established. Despite morphological features and host preference among species, coccidian with octasporozoic and monosporocystic oocysts are traditionally consider to belonging in the genus Caryospora Léger, 1904 (Apicomplexa: Eimeriidae). Recently, the genus Avispora Schuster et al., 2016 was proposed for above caryosporoids parasitizing birds based on combined morphological and phylogenetic analyses. However, diagnostic morphological characters of the genus Avispora, the absence of Stieda and substieda bodies, has already been mentioned in the description of the genus Eumonospora Allen, 1933 (Apicomplexa: Sarcocystidae), and thus Avispora is considered to be a junior synonym of Eumonospora. In this study, caryosporoid coccidians were detected from five owl species; Bubo scandiacus, Ptilopsis leucotis, Athene noctua, Strix nebulosa, and Pulsatrix perspicillata (Strigiformes: Strigidae) and identified as Avispora henryae (Yakimoff & Matikaschwaili, 1932) described from Bubo bubo (Strigiformes: Strigidae). Eumonospora henryae (Yakimoff & Matikaschwili, 1932) comb. nov. is redescribed for this species based not only on morphological features but also on phylogenetical analyses. The key of the genus Eumonospora and a list to the species known at present are also provided.

Ubiquitous waterborne pathogens

Water is one of the most important substances on earth and without it life cannot exist. However, poor water quality in many parts of the world has increased the number of water-related diseases, making it the leading cause of disease and death globally for both young and old. Waterborne pathogens cause diseases in humans through two major exposure pathways: drinking water and recreational waters. This chapter on waterborne pathogens will be starting with an introduction, followed by descriptions on classical waterborne pathogens; bacteria, viruses, protozoans, and helminths placing emphasis on the World Health Organization guidelines. Further to conventional waterborne pathogens, fresh organisms and new strains from already known pathogens are being identified and that present important additional challenges to both the water and public health sectors. Hence later part of the chapter focuses on the potential waterborne pathogens and will conclude with a summary of the content.

Ultrastructural Characteristics of Gallbladder Epithelial Inclusions Mimicking Cystoisospora

OBJECTIVES

There is recently reported increased prevalence of Isospora organisms in cholecystectomy specimens from immunocompetent patients, especially in acalculous cholecystectomies. We performed an ultrastructural and molecular evaluation of these specimens.

METHODS

From 28 gallbladders with intraepithelial inclusions, two specimens with diffuse involvement of the gallbladder epithelium were analyzed by electron microscopy. Polymerase chain reaction was performed on five samples for the ITS2 region of C belli and eukaryotic 18S region. The 18S products were sequenced by next-generation sequencing.

RESULTS

Electron microscopic analysis showed cytoplasmic condensations leading to vacuole formation. In contrast with true C belli, there were no identifiable organelles or organization. None of these cases showed amplified products other than human on molecular analysis.

CONCLUSIONS

Electron microscopic analysis demonstrates that the inclusions are condensed cytoplasmic material and not true organisms.

Cystoisospora belli infections in humans: the past 100 years

Cystoisospora belli is a coccidian parasite of humans, with a direct fecal-oral transmission cycle. It is globally distributed, but mainly found in tropical and subtropical areas. Many cases of C. belli infections have been reported in patients with HIV, and in patients undergoing immunosuppressive therapy for organ transplants or those treated for tumours worldwide. Unsporulated or partially sporulated oocysts of C. belli are excreted in feces. When sporulated oocysts in contaminated water or food are ingested, asexual and sexual stages of C. belli are confined to the epithelium of intestines, bile ducts and gallbladder. Monozoic tissue cysts are present in extra-intestinal organs (lamina propria of the small and large intestine, lymph nodes, spleen, and liver) of immunosuppressed humans. However, a paratenic host has not been demonstrated. Cystoisospora belli infections can be persistent, lasting for months, and relapses are common; the mechanism of relapse is unknown. Recently, the endogenous stages of C. belli were re-examined and attention was drawn to cases of misidentification of non-protozoal structures in the gallbladder of patients as C. belli. Here, we review all aspects of the biology of C. belli, including morphology, endogenous stages, prevalence, epidemiology, symptoms, diagnosis and control.

Parasite infections in a social carnivore: Evidence of their fitness consequences and factors modulating infection load

There are substantial individual differences in parasite composition and infection load in wildlife populations. Few studies have investigated the factors shaping this heterogeneity in large wild mammals or the impact of parasite infections on Darwinian fitness, particularly in juveniles. A host's parasite composition and infection load can be shaped by factors that determine contact with infective parasite stages and those that determine the host's resistance to infection, such as abiotic and social environmental factors, and age. Host-parasite interactions and synergies between coinfecting parasites may also be important. We test predictions derived from these different processes to investigate factors shaping infection loads (fecal egg/oocyte load) of two energetically costly gastrointestinal parasites: the hookworm Ancylostoma and the intracellular Cystoisospora, in juvenile spotted hyenas (Crocuta crocuta) in the Serengeti National Park, in Tanzania. We also assess whether parasite infections curtail survival to adulthood and longevity. Ancylostoma and Cystoisospora infection loads declined as the number of adult clan members increased, a result consistent with an encounter-reduction effect whereby adults reduced encounters between juveniles and infective larvae, but were not affected by the number of juveniles in a clan. Infection loads decreased with age, possibly because active immune responses to infection improved with age. Differences in parasite load between clans possibly indicate variation in abiotic environmental factors between clan den sites. The survival of juveniles (<365 days old) to adulthood decreased with Ancylostoma load, increased with age, and was modulated by maternal social status. High-ranking individuals with low Ancylostoma loads had a higher survivorship during the first 4 years of life than high-ranking individuals with high Ancylostoma loads. These findings suggest that high infection loads with energetically costly parasites such as hookworms during early life can have negative fitness consequences.

Promising Plant-Derived Adjuvants in the Development of Coccidial Vaccines

Coccidial parasites cause medical and veterinary diseases worldwide, frequently leading to severe illness and important economic losses. At present, drugs, chemotherapeutics and prophylactic vaccines are still missing for most of the coccidial infections. Moreover, the development and administration of drugs and chemotherapeutics against these diseases would not be adequate in livestock, since they may generate unacceptable residues in milk and meat that would avoid their commercialization. In this scenario, prophylactic vaccines emerge as the most suitable approach. Subunit vaccines have proven to be biologically safe and economically viable, allowing researchers to choose among the best antigens against each pathogen. However, they are generally poorly immunogenic and require the addition of adjuvant compounds to the vaccine formulation. During the last decades, research involving plant immunomodulatory compounds has become an important field of study based on their potential pharmaceutical applications. Some plant molecules such as saponins, polysaccharides, lectins and heat shock proteins are being explored as candidates for adjuvant/carriers formulations. Moreover, plant-derived immune stimulatory compounds open the possibility to attain the main goal in adjuvant research: a safe and non-toxic adjuvant capable of strongly boosting and directing immune responses that could be incorporated into different vaccine formulations, including mucosal vaccines. Here, we review the immunomodulatory properties of several plant molecules and discuss their application and future perspective as adjuvants in the development of vaccines against coccidial infections.

Age-specific gastrointestinal parasite shedding in free-ranging cheetahs (Acinonyx jubatus) on Namibian farmland

The cheetah (Acinonyx jubatus Brookes 1828) is classified as "vulnerable" by the International Union for Conservation of Nature (IUCN). Threats to cheetah populations are a decrease of suitable habitats, an increase of conflicts with livestock farmers and potentially pathogens. While there is some information on the viral and bacterial pathogens circulating in cheetah populations, information on gastrointestinal parasites is scarce. Here, we investigate the gastrointestinal parasites in 39 free-ranging cheetahs in east-central Namibia using a coproscopical parasitological method. Most cheetahs (82%) shed eggs from Ancylostoma which comprised the majority of the total eggs in feces. Eggs and oocysts from Toxascaris (21% of cheetahs), Coccidia (13%), Physaloptera (8%), Taeniidae (5%), Dipylidium (3%), and Diphyllobothriidae (3%) were present at a lower prevalence. Parasite richness and Ancylostoma egg load were higher in juveniles and adults compared to cubs, but were not associated with sex. To our knowledge, this is the first study that assessed gastrointestinal parasites in free-ranging cheetahs and is a key starting point for future studies on the effect of parasites in this threatened species.

Unexpectedly High Prevalence of Cystoisospora belli Infection in Acalculous Gallbladders of Immunocompetent Patients

Objectives

Indications for cholecystectomy have changed dramatically over the past three decades. Cystoisospora belli has been reported in cholecystectomy specimens of immunocompetent patients. The present study was designed to determine the prevalence and clinical association of C belli in the gallbladder.

Methods

The study included retrospective review of cholecystectomy specimens (n = 401) removed for various indications, and a prospective cohort of cholecystectomy specimens (n = 22) entirely submitted for histologic evaluation. Correlations of presence of C belli with age, sex, clinical indication, and abnormalities of preoperative laboratory values were assessed by Fisher exact test.

Results

C belli was identified in 39/401 (9.7%) of the retrospective cohort, and 6/22 (27.3%) of the entirely submitted specimens. The presence of C belli showed no correlation with age, sex, clinical indication, or laboratory abnormalities.

Conclusions

C belli resides in a latent state in the gallbladder and may be best considered a commensal organism.

Intestinal Protozoa in Domestic Cats (Carnivora: Felidae, Felis catus) in Northwestern Iran: A Cross-Sectional Study with Prevalent of Microsporidian and Coccidian Parasites

BACKGROUND

In this study, some microsporidial and coccidian parasites were isolated from 103 domestic cats in the Meshkin Shahr area, northwestern Iran during the Jun 2014 to Jun 2015, and their genera were identified using parasitological methods with emphasis on their zoonotic importance.

METHODS

One hundred and three fecal samples of domestic cats were collected and preserved in formalin (10%) and conserved in phosphate buffer saline solution, finally examined by microscopy after formalin-ether concentration and specific staining. Preservation in dichromate potassium (2.5%) was performed for all coccidian positive samples and then sporulated coccidian oocysts were investigated.

RESULTS

The detected parasites were Isospora spp. 6/103(5.8%). Microsporidian spores were identified in 46/103 (44.6%) of all samples post-stained by the aniline blue staining method.

CONCLUSION

Microsporidial infections were more prevalent in domestic cats. Further studies are needed in the identification of microsporidial spores isolated from infected cats.

Parasitic Diseases

Captive marmosets, whether in zoos or biomedical research facilities, may become infected or infested with a variety of internal or external parasites. Modern animal housing and husbandry practices have greatly reduced the prevalence of parasitism, particularly for those parasites requiring an intermediate host. In this chapter, the author discusses selected parasitic diseases of captive marmosets. This chapter is organized phylogenetically. No attempt is made to cover all of the internal and external parasites historically reported, no matter how infrequently. Similarly, no attempt is made to cover parasites infecting or infesting other New World primates and thus potentially found in or on marmosets. The author has included those parasitisms most likely to be observed in modern animal facilities.

Histochemistry in the diagnosis of non-neoplastic gastrointestinal disorders

The alimentary tract serves as host to a large number of diseases. In the non-neoplastic group of disorders, conventional histochemistry continues to play an important diagnostic role. It is particularly important in recognizing specific infectious diseases, such as Helicobacter gastritis, Whipple disease, intestinal tuberculosis and other forms of mycobacteriosis, malakoplakia, intestinal spirochetosis, fungal enteritides, amebiasis, cryptosporidiosis, isosporiasis, and microsporidiosis. Those conditions and their histochemical properties are discussed in this review, along with the use of histochemistry in the characterization of structural gastrointestinal disorders. The latter include mucosal metaplasias, amyloidosis, glycogenic acanthosis of the esophagus, lymphocytic-collagenous colitis, gastric neuroendocrine hyperplasia, and pill gastritis.

Epithelial Inclusions in Gallbladder Specimens Mimic Parasite Infection: Histologic and Molecular Examination of Reported Cystoisospora belli Infection in Gallbladders of Immunocompetent Patients

Recent publications have described epithelial cytoplasmic vacuoles and inclusions incidentally noted within gallbladder epithelium and concluded that they represent coccidian parasite infection, in particular, Cystoisospora belli. We identified 8 gallbladder specimens from our institution in the past 3 years in which this diagnosis was suggested or in which similar epithelial alterations were prominent. Molecular analysis was performed on the 8 gallbladder specimens and on 3 positive control specimens: small bowel biopsies from acquired immunodeficiency syndrome patients with diarrhea. Polymerase chain reaction using primers designed to amplify an internal transcribed spacer (ITS2) in the C. belli ribosomal gene cluster was performed on the DNA samples. All 8 gallbladder specimens were negative for amplification, while a product consistent with C. belli was amplified from all 3 positive controls. Histologically, the gallbladder cytoplasmic inclusions stained diffusely positive for Grocott-Gomori's methenamine silver and Periodic acid-Schiff with diastase. In contrast, sections from a positive control small bowel biopsy demonstrated organisms that were negative for Grocott-Gomori's methenamine silver and showed a distinct capsular and punctate internal staining on Periodic acid-Schiff with diastase in various parasite forms. Together, the lack of molecular evidence of C. belli and the distinct morphologic and special staining patterns in these gallbladders compared with positive control small bowel suggest that these epithelial changes do not represent true C. belli infection. Our results suggest that gallbladders of immunocompetent patients may occasionally show epithelial changes that can morphologically mimic C. belli infection. Pathologists should be aware of this histologic variant to minimize unnecessary treatment, testing, and patient anxiety.

Detection of Cystoisospora suis in faeces of suckling piglets - when and how? A comparison of methods

Background

Cystoisospora suis is the causative agent of porcine neonatal coccidiosis, a diarrheal disease which affects suckling piglets in the first weeks of life. Detection of oocysts in the faeces of infected animals is frequently hampered by the short individual excretion period and the high fat content of faecal samples. We analysed oocyst excretion patterns of infected piglets, evaluated different detection methods for their detection limit and reproducibility, and propose a sampling scheme to improve the diagnosis of C. suis in faecal samples from the field using a protocol for reliable parasite detection.

Results

Based on a hypothesized model of the course of infection on a farm, three samplings (days of life 7–14-21 or 10–15-20) should be conducted including individual samples of piglets from each sampled litter. Samples can be examined by a modified McMaster method (lower detection limit: 333 oocysts per gram of faeces, OpG), by examining faecal smears under autofluorescence (lower detection limit: 10 OpG) or after carbol-fuchsin staining (lower detection limit: 100 OpG). Reproducibility and inter-test correlations were high with (R² > 0.8). A correlation of oocyst excretion with diarrhoea could not be established so samples with different faecal consistencies should be taken. Pooled samples (by litter) should be comprised of several individual samples from different animals.

Conclusions

Since oocyst excretion by C. suis-infected piglets is usually short the right timing and a sufficiently sensitive detection method are important for correct diagnosis. Oocyst detection in faecal smears of samples taken repeatedly is the method of choice to determine extent and intensity of infection on a farm, and autofluorescence microscopy provides by far the lowest detection limit. Other methods for oocyst detection in faeces are less sensitive and/or more labour- and cost intensive and their usefulness is restricted to specific applications.

Gastrointestinal Parasites in Shelter Dogs: Occurrence, Pathology, Treatment and Risk to Shelter Workers

Dogs entering shelters can carry gastrointestinal parasites that may pose serious risks to other animals, shelter staff and visitors. Shelters provide an environment that could facilitate the spread of parasitic infections between animals. Nematodes and protozoa that transmit through ingestion or skin penetration are major enteric parasites of concern in shelter settings. Ancylostoma spp., Uncinaria stenocephala, Toxocara canis, Toxascaris leonina, Trichuris vulpis and Dipylidium caninum are the major helminths while Giardia, Cryptosporidium, Isospora spp. and Sarcocystis spp. are the most prevalent protozoan parasites in shelter dogs. The prevalence of gastrointestinal parasites in shelter dogs is typically higher than in owned dogs. A range of cost-effective drugs is available for prevention and control of helminths in shelters, notably fenbendazole, pyrantel, oxantel, and praziquantel. Parasiticide options for protozoan parasites are often cost-prohibitive or limited by a lack of veterinary registration for use in dogs. Environmental control measures reliant upon hygiene and facility management are therefore a mainstay for control and prevention of protozoan parasites in shelters. This philosophy should also extend to helminth control, as integrated parasite control strategies can allow anthelmintics to be used more sparingly and judiciously. The purpose of this article is to comprehensively review the current knowledge on the prevalence of gastrointestinal parasites most commonly found in dogs in shelters, canvass recommended treatment programs in shelter dogs, and to explore the likelihood that parasiticide resistance might emerge in a shelter environment.

Development and application of a recombinant protein-based indirect ELISA for the detection of serum antibodies against Cystoisospora suis in swine

The apicomplexan parasite Cystoisospora suis which causes neonatal porcine coccidiosis is one of the predominant parasite in suckling piglets. Currently, the immunofluorescence antibody test (IFAT) is the only available serological tool for detecting serum antibodies against C. suis which has several limitations, including bias from interpretation and low throughput. In the present study, an indirect enzyme-linked immunosorbent assay (ELISA) was developed using a previously characterized recombinant merozoite protein for the detection of specific immunoglobulin G (IgG) and IgA against C. suis. The recombinant protein was expressed in Escherichia coli as a N-terminal histidine fusion protein, and its specificity was confirmed in an immunoblot probed with highly positive anti-C. suis sera from experimentally infected piglets. Optimal dilutions of recombinant protein, sera and conjugate were determined by checkerboard titrations, and the serum dilution that gave the greatest ratio between the positive and the negative sera was selected for subsequent analyses. Agreement between the IFAT and the newly developed ELISA was assessed with kappa statistics. The receiver operating characteristic (ROC) curve analysis based on 185 serum samples with known C. suis exposure previously tested in the reference IFAT was used to determine the cut-off value, sensitivity and specificity of the ELISA. For IgG, the ELISA had an estimated cut-off value of 0.82 and sensitivity and specificity values of 94.7% and 98%, respectively, whereas for IgA the estimated cut-off value was 0.41 and sensitivity and specificity values were both100%. According to kappa coefficient, an excellent correlation (κ > 0.8) was found between IFAT and ELISA for both isotypes. The diagnostic accuracy of the test measured as the area under the ROC curve index scaled between 0.98 and 1.0, indicating high discriminatory capacity and its possible application as a serological tool for detecting antibody response in the host following C. suis exposure/immunization and large-scale surveillance studies.

Pathogens transmitted in animal feces in low- and middle-income countries

Animals found in close proximity to humans in low-and middle-income countries (LMICs) harbor many pathogens capable of infecting humans, transmissible via their feces. Contact with animal feces poses a currently unquantified-though likely substantial-risk to human health. In LMIC settings, human exposure to animal feces may explain some of the limited success of recent water, sanitation, and hygiene interventions that have focused on limiting exposure to human excreta, with less attention to containing animal feces. We conducted a review to identify pathogens that may substantially contribute to the global burden of disease in humans through their spread in animal feces in the domestic environment in LMICs. Of the 65 potentially pathogenic organisms considered, 15 were deemed relevant, based on burden of disease and potential for zoonotic transmission. Of these, five were considered of highest concern based on a substantial burden of disease for which transmission in animal feces is potentially important: Campylobacter, non-typhoidal Salmonella (NTS), Lassa virus, Cryptosporidium, and Toxoplasma gondii. Most of these have a wide range of animal hosts, except Lassa virus, which is spread through the feces of rats indigenous to sub-Saharan Africa. Combined, these five pathogens cause close to one million deaths annually. More than half of these deaths are attributed to invasive NTS. We do not estimate an overall burden of disease from improperly managed animal feces in LMICs, because it is unknown what proportion of illnesses caused by these pathogens can be attributed to contact with animal feces. Typical water quantity, water quality, and handwashing interventions promoted in public health and development address transmission routes for both human and animal feces; however, sanitation interventions typically focus on containing human waste, often neglecting the residual burden of disease from pathogens transmitted via animal feces. This review compiles evidence on which pathogens may contribute to the burden of disease through transmission in animal feces; these data will help prioritize intervention types and regions that could most benefit from interventions aimed at reducing human contact with animal feces.

Feline gastrointestinal parasitism in Greece: emergent zoonotic species and associated risk factors

BACKGROUND

Feline gastrointestinal parasitism constitutes an issue of concern for veterinarians since parasites are widespread and affect animals' health and welfare. Furthermore, some of these pathogens have zoonotic potential. To provide detailed data on the current epizootiology of feline endoparasitism, a multicentric survey was conducted during 2016.

METHODS

Faeces from 1150 cats were collected from all regions of Greece and examined by sedimentation and flotation techniques. Possible risk factors including gender, age, ownership status, living conditions and co-infections with other parasites were assessed using binary regression models for each one of the most prevalent parasites.

RESULTS

The overall gastrointestinal parasite prevalence in cats was 50.7%. The study population consisted of cats of both sexes, different age groups, ownership status and living conditions. A total of 10 gastrointestinal parasitic species were detected and up to 5 different parasites were isolated in the same faecal sample. The most frequently identified parasites were Toxocara cati (n = 278; 24.2%), followed by Cystoisospora spp. (n = 189; 16.4%), Ancylostomatidae (n = 186; 16.2%), Aelurostrongylus abstrusus (n = 40; 3.5%), Giardia spp. (n = 26; 2.3%), Joyeuxiella pasqualei (n = 14; 1.2%), Capillaria aerophila (n = 8; 0.7%), Dipylidium caninum (n = 3; 0.2%), Toxascaris leonina (n = 2; 0.1%) and Troglostrongylus brevior (n = 2; 0.1%). The occurrence of co-infections was 11.6%. Concerning risk factors, the likelihood of T. cati infection was higher for female cats living outdoors and for cats being infected with Cystoisospora spp. In the same frame, young, stray, male and free of A. abstrusus cats were more likely to be infected with Cystoisospora spp. Correspondingly, stray, infected with Giardia spp. but free of Cystoisospora spp. cats were more likely to be infected with Ancylostomatidae. Regarding A. abstrusus infection, a higher probability was reported for cats living outdoors and for cats free of Cystoisospora spp., while Giardia spp. infections were more common in young and co-infected with Ancylostomatidae animals.

CONCLUSIONS

The prevalence of parasitized cats in Greece was high and thus consideration should be paid to control the risk factors, to implement targeted preventive antiparasitic treatments and educate cat owners on the value of prevention for the health and welfare of their cats.

A new species of Cystoisospora Frenkel, 1977 (Apicomplexa: Sarcocystidae) from Oecomys mamorae Thomas (Rodentia: Cricetidae) in the Brazilian Pantanal

Despite the great diversity of coccidians, to our knowledge, no coccidian infections have been described in Oecomys spp. In this context, we examined Oecomys mamorae Thomas (Rodentia: Cricetidae) from the Brazilian Pantanal for infections with enteric coccidia. Nine individuals were sampled, and one was found to be infected. The oöcysts were recovered through centrifugal flotation in sugar solution. Using morphological and morphometric features, we described a new species of Cystoisospora Frenkel, 1977. Sporulated oöcysts were ovoidal 20.0-29.1 × 16.4-23.2 (26.7 × 21.2) µm and contained two sporocysts, 12.9-19.1 × 9.4-13.9 (16.4 × 12.4) µm, each with four banana-shaped sporozoites. Polar granule and oöcyst residuum were both absent. We documented the developmental forms in the small intestine and described the histopathological lesions in the enteric tract. Our results indicate that the prevalence of Cystoisospora mamorae n. sp. in O. mamorae is low, and tissue damage in the enteric tract is mild, even in the presence of coccidian developmental stages.

Genomic and Proteomic Evidence for the Presence of a Peroxisome in the Apicomplexan Parasite Toxoplasma gondii and Other Coccidia

Apicomplexans are successful parasites responsible for severe human diseases including malaria, toxoplasmosis, and cryptosporidiosis. For many years, it has been discussed whether these parasites are in possession of peroxisomes, highly variable eukaryotic organelles usually involved in fatty acid degradation and cellular detoxification. Conflicting experimental data has been published. With the age of genomics, ever more high quality apicomplexan genomes have become available, that now allow a new assessment of the dispute. Here, we provide bioinformatic evidence for the presence of peroxisomes in Toxoplasma gondii and other coccidians. For these organisms, we have identified a complete set of peroxins, probably responsible for peroxisome biogenesis, division, and protein import. Moreover, via a global screening for peroxisomal targeting signals, we were able to show that a complete set of fatty acid β-oxidation enzymes is equipped with either PTS1 or PTS2 sequences, most likely mediating transport of these factors to putative peroxisomes in all investigated Coccidia. Our results further imply a life cycle stage-specific presence of peroxisomes in T. gondii and suggest several independent losses of peroxisomes during the evolution of apicomplexan parasites.

Genotypic Identification of Cystoisospora in Immunocompromised Patients Using Tm-Variation Analysis

Cystoisospora is responsible for morbidity in immunocompromised patients. PCR is sensitive for diagnosing Cystoisospora; however, it needs reevaluation for differential molecular diagnosis of cystoisosporiasis. We aimed at evaluating melting curve analysis (MCA) after real-time PCR (qPCR) in diagnosis and genotyping of Cystoisospora as an alternative to conventional PCR. We included 293 diarrheic stool samples of patients attending the Department of Clinical Oncology and Nuclear Medicine of Cairo University Hospitals, Egypt. Samples were subjected to microscopy, nested PCR (nPCR), and qPCR targeting the internal transcribed spacer 2 region (ITS2) of the ribosomal RNA (r RNA) gene followed by melting temperatures (T_ms) analysis and comparing the results to PCR-RFLP banding patterns. Using microscopy and ITS2-nPCR, 3.1% and 5.8% of cases were Cystoisospora positive, respectively, while 10.9% were positive using qPCR. Genotyping of Cystoisospora by qPCR-MCA revealed 2 genotypes. These genotypes matched with 2 distinct melting peaks with specified T_ms at 85.8°C and 88.6°C, which indicated genetic variation among Cystoisospora isolates in Egypt. Genotype II proved to be more prevalent (65.6%). HIV-related Kaposi sarcoma and leukemic patients harbored both genotypes with a tendency to genotype II. Genotype I was more prevalent in lymphomas and mammary gland tumors while colorectal and hepatocellular tumors harbored genotype II suggesting that this genotype might be responsible for the development of cystoisosporiasis in immunocompromised patients. Direct reliable identification and differentiation of Cystoisospora species could be established using qPCR-T_ms analysis which is useful for rapid detection and screening of Cystoisospora genotypes principally in high risk groups.

Practical Guidance for Clinical Microbiology Laboratories: Laboratory Diagnosis of Parasites from the Gastrointestinal Tract

This Practical Guidance for Clinical Microbiology document on the laboratory diagnosis of parasites from the gastrointestinal tract provides practical information for the recovery and identification of relevant human parasites. The document is based on a comprehensive literature review and expert consensus on relevant diagnostic methods. However, it does not include didactic information on human parasite life cycles, organism morphology, clinical disease, pathogenesis, treatment, or epidemiology and prevention. As greater emphasis is placed on neglected tropical diseases, it becomes highly probable that patients with gastrointestinal parasitic infections will become more widely recognized in areas where parasites are endemic and not endemic. Generally, these methods are nonautomated and require extensive bench experience for accurate performance and interpretation.

Regression models to assess the risk factors of canine gastrointestinal parasitism

Gastrointestinal parasites, protozoa and helminths, remain a common important finding in dogs presented to veterinary medical practices. Moreover, dogs may play an active role in the transmission of enteric parasites to humans, given their cohabitation, making canine gastrointestinal parasitism an issue of major concern for public health. To get an overview of the current state of canine gastrointestinal parasites' prevalence in Greece, a total of 1036 faecal samples were collected from dogs either presented in veterinary clinics or in animal shelters. Samples were examined by a combined sedimentation-flotation technique. Possible risk factors (age, ownership status, co-existence with other animals, coinfection with other parasites) were assessed using binary regression models for each one of the most prevalent parasites. The overall gastrointestinal parasite prevalence in dogs' faecal samples was 39%. A total of 11 intestinal parasitic species were detected and up to five different parasites were isolated in the same faecal sample. Toxocara canis was the most prevalent parasite in the studied population, followed by Isospora spp., Giardia spp., Uncinaria spp., Trichuris vulpis, Ancylostoma spp., Toxascaris leonina, and Dipylidium caninum. Additionally, other genera (Taenia, Capillaria and Angiostrongylus) were also detected in very low percentages. Young, stray, living without other dogs, coinfected with T. vulpis or T. canis and free of Isospora spp. dogs were more likely to be infected by Giardia spp. Likewise, young, stray, coinfected with T. vulpis or T. canis but free of Giardia spp. dogs were more likely to be infected by Isospora spp. T. canis infections were more common in dogs coinfected with Isospora spp., Giardia spp., D. caninum, Τaenia spp., T. vulpis and T. leonina Finally, T. vulpis more often infected older dogs and dogs coinfected with Isospora spp., Giardia spp. and T. canis Consequently, the prevalence of parasitized dogs was high and the diversity of parasites found was notable, which calls for a greater awareness among veterinarians and pet owners. The proposed prediction models should be taken under consideration in diagnostic approach of clinical cases, as well as in planning sustainable antiparasitic strategies.

Uncommon and fatal case of cystoisosporiasis in a non HIV-immunosuppressed patient from a non-endemic country

Cystoisospora belli (previously known as Isospora belli) is a tropical coccidian parasite sometimes leading to severe diarrhea in immunocompromised patients. Here we describe a fatal case of cystoisosporiasis in a non HIV-immunocompromised 71-year-old female with no recent travel history. Infection was either latent or potentially caused by the consumption of contaminated imported food from Asia. Diagnosis was made by microscopical detection of numerous C. belli oocysts in stools without specific staining. Treatment with TMP-SMZ slightly improved diarrhea within 3days, but dehydration subsequently led to acute decompensated heart failure and a fatal evolution. This report illustrates the possibility of severe cystoisosporiasis in non HIV-immunocompromised patients in a non-endemic country and highlights the risk of transmission through imported contaminated food consumption.

Gastrointestinal parasites in stray and shelter cats in the municipality of Rio de Janeiro, Brazil

Abstract The increasingly urban nature of the population has led many people to choose independent pets, such as cats. This situation has also made it possible for these animals to be abandoned, thus increasing the numbers of cats on the streets and in shelters. These animals can act as a source of infection for other hosts. Between 2014 and 2015, the frequency of gastrointestinal parasites in captive and stray cats in the municipality of Rio de Janeiro was analyzed. Ninety-one fecal samples were collected from captive cats and 172 from stray cats. Centrifugal sedimentation and flotation techniques were used. The frequency of parasites among the stray cats was 77.3%, and this was significantly higher than the frequency observed in captive cats (49.5%). Helminths were detected more frequently, and hookworms were the parasites most detected. Toxocara cati, Cystoisospora sp. and Dipylidium caninum were also detected. No statistical difference in the frequency of parasites was observed between the sexes among the captive cats. However, among the stray cats, males (85.5%) presented higher positivity than females (71.8%). The high frequency of hookworms, which are the agent for “cutaneous larva migrans” in humans, shows the need to control parasitic infections among the cats studied.

Dogs' Gastrointestinal Parasites and their Association with Public Health in Iran

INTRODUCTION

Dogs harbour zoonotic parasites that cause serious infections in humans, such as visceral larva migrans, ocular larva migrans, cystic echinococcosis, and alveolar echinococcosis. Studies on dogs' gastrointestinal parasites in different geographical locations are required to increase knowledge of the risk of canine zoonoses in human populations.

MATERIAL AND METHODS

The presence of parasites was examined in 450 faecal samples collected from eight zones of Zanjan province, northwest Iran from June to November 2015. The samples were examined using the sedimentation concentration method and modified Ziehl-Neelsen staining.

RESULTS

Gastrointestinal parasites were found in 86 (19.1%) faecal samples. Sarcocystis spp. (7.3%), Taenia/Echinococcus spp. (5.6%), Toxocara spp. (1.8%), and Cystoisospora spp. (1.6%) were the most common parasites observed. The other detected parasites consisted of Dicrocoelium dendriticum (0.7%), Eimeria spp. (0.7%), Cryptosporidium spp. (0.4%), Physaloptera spp. (0.4%), Giardia spp. (1.3%), and Spirocerca lupi (1.3%). The lowest parasite infection rates belonged to Trichuris vulpis and Acanthocephalans (0.2% each).

CONCLUSION

This study provides current information on the infection rates in dog populations in Zanjan Province. Furthermore, the study shows a high prevalence of gastrointestinal parasitic infections, including zoonotic ones and particularly Taenia/Echinococcus spp., potentially transmissible to humans and thus relevant to public health.

Successful therapeutic management of canine Isosporosis in puppies

Four labrador male puppies were confirmed for the Isospora spp infection by direct smear and flotation method following complains of anorexia, haematemesis and haematochezia. The puppies were treated with trimethoprime and sulphamethoxazole @ 40 mg/kg body weight in combination with metronidazole @ 10 mg/kg body weight twice daily for 5 days which was supported with fluid therapy, aniemetics and plasma expanders. All the animals showed completed clinical recovery along with clearing of faecal oocyst.

Smelling fit: scent marking exposes parasitic infection status in the banded mongoose

Preference for uninfected mates is presumed beneficial as it minimizes one’s risk of contracting an infection and infecting one’s offspring. In avian systems, visual ornaments are often used to indicate parasite burdens and facilitate mate choice. However, in mammals, olfactory cues have been proposed to act as a mechanism allowing potential mates to be discriminated by infection status. The effect of infection upon mammalian mate choice is mainly studied in captive rodents where experimental trials support preference for the odors of uninfected mates and some data suggest scent marking is reduced in individuals with high infection burdens. Nevertheless, whether such effects occur in nonmodel and wild systems remains poorly understood. Here, we investigate the interplay between parasite load (estimated using fecal egg counts) and scent marking behavior in a wild population of banded mongooses Mungos mungo. Focusing on a costly protozoan parasite of the genus Isospora and the nematode worm Toxocara, we first show that banded mongooses that engage in frequent, intensive scent marking have lower Isospora loads, suggesting marking behavior may be an indicator trait regarding infection status. We then use odor presentations to demonstrate that banded mongooses mark less in response to odors of opposite sexed individuals with high Isospora and Toxocara loads. As both of these parasites are known to have detrimental effects upon the health of preweaned young in other species, they would appear key targets to avoid during mate choice. Results provide support for scent as an important ornament and mechanism for advertising parasitic infection within wild mammals.