Coccidian Parasites Research Articles

Three new species of Eimeria (Apicomplexa: Eimeriidae) from the Amami rabbit, Pentalagus furnessi (Mammalia: Leporidae).

The Amami rabbit, Pentalagus furnessi (Mammalia: Lagomorpha: Leporidae), is a relict and endangered species endemic to the Amami-Oshima and Tokunoshima Islands, located in southwestern Japan. Here, we described three new species of Eimeria (Apicomplexa: Eimeriidae) parasites detected from fecal samples of wild Amami rabbits. Eimeria furnessi n. sp., recorded in 21 (58.3%) samples, has ellipsoidal oocysts with two walls and micropyle, 26.0 × 16.6 μm, and elongate-ovoidal sporocysts, 13.1 × 6.3 μm, with Stieda body. Eimeria hilleri n. sp., recorded in 9 (25.0%) samples, has ellipsoidal oocysts with two walls and micropyle, 34.7 × 21.4 μm, and elongate-fusiform to elongate-ovoidal sporocysts, 15.7 × 8.3 μm, with Stieda and substieda bodies. Eimeria sagentae n. sp., recorded in 13 (36.1%) samples, has ellipsoidal oocysts with two walls and micropyle, 20.9 × 14.5 μm, and elongate-ovoidal sporocysts, 10.4 × 5.0 μm, with Stieda body. The three new species can be distinguished by the size and color of their oocysts. Further studies related to the pathogenicity of these parasites can improve the breeding and propagation procedures of the Amami rabbit.

A New Isospora (Apicomplexa: Eimeriidae) from the Carolina Wren, Thryothorus ludovicianus ludovicianus (Passeriformes: Certhioidea: Troglodytidae), in Southeastern Oklahoma, USA.

Nothing is known of the coccidian parasites of the Carolina wren, Thryothorus ludovicianus ludovicianus (Latham, 1790). Here, we report a new species of Isospora from T. l. ludovicianus from Oklahoma, USA. Faecal samples were collected between September and December 2021 from five adult T. l. ludovicianus taken with a mist net from McCurtain County, Oklahoma, USA, and examined for coccidian parasites. Samples were placed in individual vials containing aqueous potassium dichromate. They were examined for coccidia after flotation in Sheather's sugar solution, measured, and photographed. Tissue samples from the intestine of a single positive bird were removed and placed in 10% neutral-buffered formalin for examination of coccidian endogenous stages. A single Carolina wren (20%) was found to be passing a new species of Isospora. Oocysts of Isospora edwardwilsoni n. sp. were subspheroidal to ovoidal with a smooth bi-layered wall, measured (L × W) 23.8 × 20.3µm, and had a length/width (L/W) ratio of 1.2; a micropyle and oocyst residuum was absent but typically one to up to four polar granule(s) was present. Sporocysts are ovoidal to ellipsoidal and measured 15.3 × 9.7µm, L/W 1.6; a knob-like Stieda body was present as well as a distinct rounded sub-Stieda body. The sporocyst residuum was composed of various-sized granules in a compact irregular mass or dispersed between and across the sporozoite, or a combination of both within the same sporocyst. Information is also presented on the endogenous development of this coccidian. This is the first coccidian reported from T. l. ludovicianus and, more importantly, the first known from the members of the family Troglodytidae in North America.

Prevalence, Intensity, and Risk Factors for Helminth Infections in Pigs in Menoua, Western Highlands of Cameroon, with Some Data on Protozoa.

Helminthes affect satisfactory pig farming by causing poor growth rate and infertility. The objective of this study was to investigate the occurrence of helminthes in pig production, as well as factors influencing their prevalence in Menoua, Western Highlands of Cameroon. Thus, 597 fecal samples from 100 farms of three production types (farrower, grower, and farrow-to-finish) were collected together with data on farmer and management characteristics. Samples were qualitatively and quantitatively analyzed. Eggs of eight helminthes were identified: Hyostrongylus rubidus (81.10%, 50-550 epg), Strongyloides ransomi (34.5%, 50-150 epg), Trichostrongylus sp. (28.1%, 50-650 epg), Ascaris suum (11.6%, 50-200 epg), Metastrongylus sp. (10.4%, 50-250 epg), Oesophagostomum dentatum (5.7%, 50-150 epg), Trichuris suis (4.0%, 50-150 epg), and Macracanthorhynchus hirudinaceus (0.2%, 50-50 epg). The overall prevalence was 89.3% (533 out of 597). Single infestations were 30.2%, while mixed infestations were 59.1%. A. suum, S. ransomi, and strongyles (H. rubidus, Trichostrongylus sp., Metastrongylus sp., and O. dentatum) were found in almost all age groups but the prevalence of A. suum increased with the growing age to drop in older animals. H. rubidus was found in all farm types followed by S. ransomi in farrower and farrow-to-finish farms. The other parasites were present only in farrow-to-finish farms. Coccidia parasites were also found including Isospora suis (26.30%, 50-12500 oocysts per gram of feces (opg)) and Eimeria spp. (1.40%, 100-100 opg). The risk of infestation for some parasites was lower with increasing herd size, high education level of farmers, and in wooden piggeries and semipermanent structures. The infestation risk was higher for all the investigated parasites for pigs escaping the pens. The overall significance of these parasites on growth and reproduction of the naturally infested pigs deserve assessment. Necropsy studies to confirm the worm burden are needed. Risk factors were identified, thus paving the way to design successful helminth control in pig production enterprises.

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.

Are foxes (Vulpes spp.) good sentinel species for Toxoplasma gondii in northern Canada?

BackgroundIn changing northern ecosystems, understanding the mechanisms of transmission of zoonotic pathogens, including the coccidian parasite Toxoplasma gondii, is essential to protect the health of vulnerable animals and humans. As high-level predators and scavengers, foxes represent a potentially sensitive indicator of the circulation of T. gondii in environments where humans co-exist. The objectives of our research were to compare serological and molecular assays to detect T. gondii, generate baseline data on T. gondii antibody and tissue prevalence in foxes in northern Canada, and compare regional seroprevalence in foxes with that in people from recently published surveys across northern Canada.MethodsFox carcasses (Vulpes vulpes/Vulpes lagopus, n = 749) were collected by local trappers from the eastern (Labrador and Québec) and western Canadian Arctic (northern Manitoba, Nunavut, and the Northwest Territories) during the winters of 2015–2019. Antibodies in heart fluid were detected using a commercial enzyme-linked immunosorbent assay. Toxoplasma gondii DNA was detected in hearts and brains using a magnetic capture DNA extraction and real-time PCR assay.ResultsAntibodies against T. gondii and DNA were detected in 36% and 27% of foxes, respectively. Detection of antibodies was higher in older (64%) compared to younger foxes (22%). More males (36%) than females (31%) were positive for antibodies to T. gondii. Tissue prevalence in foxes from western Nunavik (51%) was higher than in eastern Nunavik (19%). At the Canadian scale, T. gondii exposure was lower in western Inuit regions (13%) compared to eastern Inuit regions (39%), possibly because of regional differences in fox diet and/or environment. Exposure to T. gondii decreased at higher latitude and in foxes having moderate to little fat. Higher mean infection intensity was observed in Arctic foxes compared to red foxes. Fox and human seroprevalence showed similar trends across Inuit regions of Canada, but were less correlated in the eastern sub-Arctic, which may reflect regional differences in human dietary preferences.ConclusionsOur study sheds new light on the current status of T. gondii in foxes in northern Canada and shows that foxes serve as a good sentinel species for environmental circulation and, in some regions, human exposure to this parasite in the Arctic.Graphical

Black-spotted pond frog Pelophylax nigromaculatus as a new host for the renal coccidian genus Hyaloklossia (Alveolata: Apicomplexa).

Hyaloklossia Labbé, 1896 (Apicomplexa: Sarcocystidae) is a renal coccidium that infects anuran species. The genus consists of two species: H. lieberkuehni, recorded from Pelophylax kl. esculentus, Pelophylax ridibundus, and Rana temporaria in Europe; and H. kasumiensis, recorded from Pelophylax porosus porosus in Japan. However, there have been no reports of Hyaloklossia in the other anurans in Japan. On June 2021, we examined a total of 58 adult frogs comprising 2 P. p. porosus, 23 Pelophylax nigromaculatus, 8 Rana japonica, 3 Glandirana rugosa (Ranidae), 13 Fejervarya kawamurai (Dicroglossidae), and 9 Buergeria buergeri (Rhacophoridae) for infection by Hyaloklossia. Microscopic examination of kidney tissues revealed a high infection incidence of 47.8% (11/23) in P. nigromaculatus, but the other frog species were negative for Hyaloklossia. Morphological and molecular analyses using nuclear ribosomal and mitochondrial genes confirmed the infective species as H. kasumiensis. This is a new host record for H. kasumiensis.

The effects of feed supplementing Akkemansia muciniphila on incidence, severity, and gut microbiota of necrotic enteritis in chickens

Akkermansia muciniphila (AM) is a mucin-degrading anaerobe, exerting beneficial effects on gut integrity improvement, inflammatory alleviation, and metabolic regulations in humans. Excess amounts of mucin and mucogenesis in the gut facilitate the development of necrotic enteritis (NE) in chickens. The study aimed to evaluate the effects of oral inoculation of AM on NE prevention and gut modulation in a NE-reproduced model coinfecting with Clostridium perfringens (CP) and Eimeria parasites. A total of 105 commercial 1-day-old broilers were randomly allocated into 5 groups, respectively challenged with Eimeria (Eimeria group), Eimeria and CP (Eimeria+CP group), Eimeria and CP with AM (Eimeria+CP+AM group), Eimeria and AM (Eimeria+AM group), and a placebo (Noninfected group). The treatment of AM exhibited a low degree of amelioration on NE severity. The application neither protected broilers from NE by decreasing NE-positive numbers nor reached a significant reduction in lesion scores in the small intestines. The development of NE reduced species diversity in jejunal microbiota; the pretreatments of AM exacerbated the consequence by losing species richness and promoted the similarity of the jejunal microbial community presented in the Eimeria+CP group. The participation of AM enhanced the increments of genera Clostridium sensu stricto 1 and Escherichia_Shigella and decreased the number of Lactobacillus. The significant variations of genera Clostridium sensu stricto 1 and Lactobacillus in jejunal microbiota were associated with NE development and promotion. In conclusion, oral inoculation of AM promoted the development of NE and modulated the jejunal microbiota favorable for CP overgrowth in broilers. The application of AM as a probiotic in broilers should be cautious on account of the effects to predispose NE.

Detection of Coccidian Parasites using Auramine Rhodamine Stain: A Rapid and Sensitive Tool

Introduction: Intestinal coccidian parasites known to cause opportunistic infections have increased since the past years and are often indistinguishable from other forms of community- acquired diarrhoea, which suggests a need for proper and rapid diagnostic techniques to recover and identify the organism. Aim: To investigate if Auramine Rhodamine (AR) staining is a sensitive and time conserving staining technique in contrast to modified acid fast stain. Materials and Methods: A descriptive observational study was conducted at Nizam’s Institute of Medical Sciences, Hyderabad, India, over a period of three months (i.e., from July to September 2019). A total of 100 stool samples received by the Department of Microbiology were subjected to macroscopic and microscopic examination by saline mount, iodine mount, kinyoun acid fast stain, modified AR staining. Results: In the present study the prevalence of coccidian infections were observed to be 6%. Coccidian parasites reported were Cryptosporidium species and Cystoisospora species immunocompromised patients were found to be more prone to infections with coccidian parasites. The AR stain showed 100% agreement with modified acid fast stain. Conclusion: This study concluded that the AR stain is a rapid and better stain than kinyoun acid-fast stain for the detection of coccidian parasites.

Evaluation of Diagnostic Techniques in Detection of Enteric Coccidian Parasites in Patients with HIV

Introduction: Diarrhoea is one of the commonest opportunistic infections seen in the course of the HIV disease and is a cause of considerable morbidity and mortality. Protozoan intestinal infections constitute one of the most important ailments affecting these immune deficient groups. Aim: To evaluate modified acid-fast staining technique with modified safranin technique in detection of enteric coccidian parasites and its correlation with Cluster of Differentiation (CD4) cell counts. Materials and Methods: A prospective cross-sectional study was done for a period of 16 months (November 2015 to March 2017) was conducted in 200 Human Immunodeficiency Virus (HIV) positive patients with diarrhoea in ABVIMS and Dr. RML hospital, Delhi, India. Three consecutive early morning stool samples (3-5 gm/3-5 mL) along with 3 mL venous blood in Becton Dickinson Ethylenediamine Tetra-Acetic Acid (BD EDTA) vial for CD4 cell estimation were collected. The smears were subjected to Kinyuon method and Modified Safranin Technique. Enzyme Linked Immunosorbent Assay (ELISA) for detection of Cryptosporidium antigen was also performed. All statistical analysis was performed using STATA version 16.1 software. Results: A total of 58 (29%) enteric coccidian parasites were detected. Isospora belli was the most common parasite in HIV positive patients followed by Cryptosporidium spp. The maximum parasitic isolation was in the patients with CD4 cell counts below 250 cells/μL. Conclusion: Routine screening of stool samples of HIV positive patients with diarrhoea should be undertaken for enteric coccidian parasites to prevent delay in diagnosis and prevention of morbidity and mortality associated with these infections.

SEROPREVALENCE OF ANTI-TOXOPLASMA GONDII ANTIBODIES IN THE MOST CONSUMED LIVESTOCK AND POULTRY IN GAZA – PALESTINE

It is commonly established that warm blooded animals are extremely vulnerable to the infectious coccidian parasite, Toxoplasma gondii. T. gondii can be transmitted to poultry and livestock through the ingestion of oocyst (fecal-oral), and placenta (congenital toxoplasmosis) in livestock. Cattle, sheep, and rabbits are some of the most consumed livestock in Palestine. As for poultry, backyard chicken, caged chicken, and caged turkeys are some of the most consumed birds. The aim of the present study is to detect the seroprevalence of Anti-T. gondii antibodies (IgG/IgM) among the frequently consumed livestock and poultry, which is collected from farms and slaughterhouses in Gaza, Palestine. For this specific study, blood samples from 213 cattle, 100 sheep, and 99 rabbits were collected. On the other hand, 50 blood samples from each type of poultry mentioned above were also collected. The criteria of samples collection based on a quick survey was performed among animal breeders and slaughterhouses owners in the study area, under the guidance of the colleagues in the Palestinian Ministry of Agriculture (veterinary department), as well as with the support of documented references as the targeted animal groups are the most suitable for meat production regardless of age and gender. The collected samples were analyzed through the use of the ELISA technique and Rapid Cassette Test. The results of the present study showed a high seroprevalence of Anti-T. gondii antibodies among sheep, which was 64.00 % and 13.14% among cattle. On the other hand, the results among backyard chicken and caged chicken were 26.00% and 2.00%, respectively. However, no antibodies were detected in the serum of rabbits and caged turkeys.

The Role of Aryl Hydrocarbon Receptor in Malaria Immunity during Adulthood, Childhood and Pregnancy: A Review

Malaria is most prevalent parasitic disease, it caused by coccidian parasite of the genus plasmodium, four species are usually infect human beings, P. falciparum, P. vivax, P. malriae and P. ovale, Most of malaria cases resulted from P. falciparum and P. vivax. Aryl hydrocarbon receptor (AHR) is an environmental sensor exists in many parts of human body such as lung, spleen, gut and breast. In this review we discussed the functions of it as regulator for proinflammatory and anti-inflammatory cytokines, the possible role of diet during pregnancy and breastfeeding in boosting immunity against malaria during pregnancy and childhood by triggering AHR. Also we hypothesize that probable role of it in synchronizing erythrocytic schizogongy. Experimental studies recommended to know more about the biological protective functions of AHR.

Thiosemicarbazone Copper Chelator BLT-1 Blocks Apicomplexan Parasite Replication by Selective Inhibition of Scavenger Receptor B Type 1 (SR-BI)

Coccidian parasites are obligate intracellular pathogens that affect humans and animals. Apicomplexans are defective in de novo synthesis of cholesterol, which is required for membrane biosynthesis and offspring formation. In consequence, cholesterol has to be scavenged from host cells. It is mainly taken up from extracellular sources via LDL particles; however, little is known on the role of HDL and its receptor SR-BI in this process. Here, we studied effects of the SR-BI-specific blocker BLT-1 on the development of different fast (Toxoplasma gondii, Neospora caninum, Besnoitia besnoiti) and slow (Eimeria bovis and Eimeria arloingi) replicating coccidian species. Overall, development of all these parasites was significantly inhibited by BLT-1 treatment indicating a common SR-BI-related key mechanism in the replication process. However, SR-BI gene transcription was not affected by T. gondii, N. caninum and B. besnoiti infections. Interestingly, BLT-1 treatment of infective stages reduced invasive capacities of all fast replicating parasites paralleled by a sustained increase in cytoplasmic Ca++ levels. Moreover, BLT1-mediated blockage of SR-BI led to enhanced host cell lipid droplet abundance and neutral lipid content, thereby confirming the importance of this receptor in general lipid metabolism. Finally, the current data suggest a conserved role of SR-BI for successful coccidian infections.

Polyether ionophore kijimicin inhibits growth of Toxoplasma gondii and controls acute toxoplasmosis in mice.

The natural polyether ionophore antibiotics may be important chemotherapeutic agents. Among them, kijimicin represents an important type of ionophore compound because it inhibits Eimeria tenella and human immunodeficiency virus. The ionophore monensin displays potent activities against several coccidian parasites including the opportunistic pathogen of humans, Toxoplasma gondii. At first, we evaluated the anti-Toxoplasma activity of kijimicin, monensin as a reference control, and anti-Toxoplasma drugs such as clindamycin, in vitro. The half inhibitory concentrations (IC50) for the anti-Toxoplasma activities of kijimicin, monensin, and clindamycin were 45.6 ± 2.4nM, 1.3 ± 1.8nM, and 238.5 ± 1.8nM, respectively. Morphological analyses by electron microscopy revealed cellular swelling and multiple intracellular vacuole-like structures in the T. gondii tachyzoites after treatment with kijimicin and monensin. Kijimicin and monensin also inhibited the invasion of extracellular parasites (IC50 = 216.6 ± 1.9pM and 531.1 ± 1.9pM, respectively). Importantly, kijimicin treatment resulted in decreased mitochondrial membrane potential and generation of reactive oxygen species in T. gondii as monensin did. Furthermore, mice treated with kijimicin at 10mg/kg/day and 3mg/kg/day showed 91.7% and 66.7% survival rates, respectively, 30days after infection with T. gondii. The control mice all died within 18days of infection. The present study shows that kijimicin inhibits T. gondii growth and changes the ultrastruct of the parasites. This finding may lead to validation of kijimicin as new drug to control T. gondii growth.

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.

Restriction fragment length polymorphism analysis of genes of virulent strain isolate of Toxoplasma gondii using enzyme DdeI

Background and Aim: Toxoplasma gondii is a unicellular coccidian parasite distributed globally and is an important zoonotic pathogen. Approximately 30% of the human population worldwide is chronically infected with T. gondii. The pathogenicity of this species depends on the type originating from the clonal population. Techniques for more accurately determining the type of T. gondii have recently been developed using genetic markers. Specifically, T. gondii has been typed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). This study aimed to identify sets of PCR-RFLP markers that have high power to discriminate genotyping of T. gondii and are easy to use and are easy to use. The objective of this study was to characterize virulent strain isolates of T. gondii by PCR-RFLP using 10 markers with DdeI. Materials and Methods: T. gondii tachyzoites (RH virulent strain) were derived from culture cells at the Indonesian Research Center for Veterinary Sciences. Genotyping was performed on T. gondii DNA extracted from cell cultured tachyzoites using 10 genetic markers of PCR-RFLP, namely, B1#1, B1#2, B1#3, SAG1#1, SAG1#2, P30, BAG1, ROP1, GRA1, and GRA7, with digestion using the restriction enzyme DdeI. Results: The 10 genes were amplified by PCR. Among them, three genetic markers, B1#3, ROP1, and GRA1, were genotyped by the PCR-RFLP using restriction enzyme DdeI. Overall, the findings showed that the specific RFLP profile of digestion of gene regions by DdeI could be used as a specific marker for the virulent biotype causative of toxoplasmosis. In addition, virulent strains of T. gondii can be easily detected by these markers. Conclusion: Three pairs of primers (B1#3, ROP1, and GRA1) with DdeI have proven useful for the diagnosis of acute toxoplasmosis (virulent strain biotype I). This proposed method is relatively simple, rapid, cheap, and can be performed in most laboratories, providing a practical approach for the routine analysis of T. gondii strains.

Prevalence of Cryptosporidium in Children Under 13 Years of Age With Acute Diarrhea in Tabriz, Iran

Introduction: Cryptosporidium is a coccidian parasite that causes diarrhea in animals and humans, especially children. Although several studies have been done on Cryptosporidium infection in some parts of Iran, this parasite is not examined in routine parasitological tests. Therefore, the aim of this study was to determine the frequency of Cryptosporidium infection in children with diarrhea in Tabriz, Iran. Materials and Methods: In this study, 100 fecal samples of children under 13 years of age with acute diarrhea who referred to medical diagnostic laboratories in Tabriz during 2018 were examined for Cryptosporidium infection. The samples were first concentrated by formalin-ether method and after staining with modified acid fast method, they were examined by light microscope. Results: In this study, 3 children (3%), 2 boys, 3 years old and 5 years old, and a 3-year-old girl had cryptosporidiosis. Conclusion: The results of the present study show the presence of Cryptosporidium infection in children in Tabriz. The very low percentage of infection with this parasite indicates that this parasite is not yet considered as a health problem in this area.

Dynamically expressed genes provide candidate viability biomarkers in a model coccidian.

Eimeria parasites cause enteric disease in livestock and the closely related Cyclospora cayetanensis causes human disease. Oocysts of these coccidian parasites undergo maturation (sporulation) before becoming infectious. Here, we assessed transcription in maturing oocysts of Eimeria acervulina, a widespread chicken parasite, predicted gene functions, and determined which of these genes also occur in C. cayetanensis. RNA-Sequencing yielded ~2 billion paired-end reads, 92% of which mapped to the E. acervulina genome. The ~6,900 annotated genes underwent temporally-coordinated patterns of gene expression. Fifty-three genes each contributed >1,000 transcripts per million (TPM) throughout the study interval, including cation-transporting ATPases, an oocyst wall protein, a palmitoyltransferase, membrane proteins, and hypothetical proteins. These genes were enriched for 285 gene ontology (GO) terms and 13 genes were ascribed to 17 KEGG pathways, defining housekeeping processes and functions important throughout sporulation. Expression differed in mature and immature oocysts for 40% (2,928) of all genes; of these, nearly two-thirds (1,843) increased their expression over time. Eight genes expressed most in immature oocysts, encoding proteins promoting oocyst maturation and development, were assigned to 37 GO terms and 5 KEGG pathways. Fifty-six genes underwent significant upregulation in mature oocysts, each contributing at least 1,000 TPM. Of these, 40 were annotated by 215 GO assignments and 9 were associated with 18 KEGG pathways, encoding products involved in respiration, carbon fixation, energy utilization, invasion, motility, and stress and detoxification responses. Sporulation orchestrates coordinated changes in the expression of many genes, most especially those governing metabolic activity. Establishing the long-term fate of these transcripts in sporulated oocysts and in senescent and deceased oocysts will further elucidate the biology of coccidian development, and may provide tools to assay infectiousness of parasite cohorts. Moreover, because many of these genes have homologues in C. cayetanensis, they may prove useful as biomarkers for risk.

Seroprevalence and molecular characterization of Toxoplasma gondii infecting ruminants in the North-West of Egypt

Toxoplasma gondii is a coccidian parasite known for its heavy toll on people and livestock. It can cause abortion and a variety of congenital diseases. The current study aimed to examine some seroprevalence and molecular attributes of T. gondii obtained from ruminants in the North-West of Egypt. Specimens were random selected from five different locations in Alexandria and Matrouh governorates. A total of 483 blood samples, collected from 96 mixed flocks, were screened for anti-T. gondii IgG antibodies using enzyme-linked immunosorbent assay (ELISA). The seropositive results were then confirmed using polymerase chain reaction (PCR) primers for the B1 and P30 genes. Specific PCR products were selected for sequencing and alignment against the GenBank, where phylogeny has been examined using the maximum likelihood, neighbor-joining, and maximum parsimony in MEGA6. ELISA confirmed the presence of T. gondii in 188 of the investigated samples (38.92%), indicating a higher prevalence in camels (64.51%) and sheep (43.75%) as compared to goats (27.93 %) and cattle (13.46%). PCR confirmed the presence of T. gondii-specific sequences in 159 seropositive specimens, with homology between 98.3 and 100%. The genetic distances between the investigated variants ranged from 0.1 to 0.9, and 7 single nucleotide polymorphisms (SNPs), were identified in the examined T. gondii specimens. The camel T. gondii parasite, isolated from Matrouh, showed a 100% homology with the most dangerous reference strains of T. gondii-RH in the GenBank. Our results showed that B1 and P30-specific PCR could detect T. gondii in blood samples more accurately than ELISA. In addition, the statistical analysis of our data indicated that species, age, sex, and animal location were all risk factors for toxoplasmosis. These findings are likely to boost disease control and help contain the spread of T. gondii infections.

Cyclosporiasis-Updates on Clinical Presentation, Pathology, Clinical Diagnosis, and Treatment.

Cyclospora cayetanensis is an intestinal coccidian parasite transmitted to humans through the consumption of oocysts in fecally contaminated food and water. Infection is found worldwide and is highly endemic in tropical and subtropical regions with poor sanitation. Disease in developed countries is usually observed in travelers and in seasonal outbreaks associated with imported produce from endemic areas. Recently, summertime outbreaks in the United States have also been linked to locally grown produce. Cyclosporiasis causes a diarrheal illness which may be severe in infants, the elderly, and immunocompromised individuals. The increased adoption of highly sensitive molecular diagnostic tests, including commercially available multiplex panels for gastrointestinal pathogens, has facilitated the detection of infection and likely contributed to the increased reports of cases in developed countries. This manuscript reviews important aspects of the biology, epidemiology, and clinical manifestations of C. cayetanensis and provides an in-depth discussion of current laboratory diagnostic methods.

Do All Coccidia Follow the Same Trafficking Rules?

The Coccidia are a subclass of the Apicomplexa and include several genera of protozoan parasites that cause important diseases in humans and animals, with Toxoplasma gondii becoming the ‘model organism’ for research into the coccidian molecular and cellular processes. The amenability to the cultivation of T. gondii tachyzoites and the wide availability of molecular tools for this parasite have revealed many mechanisms related to their cellular trafficking and roles of parasite secretory organelles, which are critical in parasite-host interaction. Nevertheless, the extrapolation of the T. gondii mechanisms described in tachyzoites to other coccidian parasites should be done carefully. In this review, we considered published data from Eimeria parasites, a coccidian genus comprising thousands of species whose infections have important consequences in livestock and poultry. These studies suggest that the Coccidia possess both shared and diversified mechanisms of protein trafficking and secretion potentially linked to their lifecycles. Whereas trafficking and secretion appear to be well conversed prior to and during host-cell invasion, important differences emerge once endogenous development commences. Therefore, further studies to validate the mechanisms described in T. gondii tachyzoites should be performed across a broader range of coccidians (including T. gondii sporozoites). In addition, further genus-specific research regarding important disease-causing Coccidia is needed to unveil the individual molecular mechanisms of pathogenesis related to their specific lifecycles and hosts.