Intestinal Protozoan Parasite Research Articles

Molecular detection and identification of Enteromonas species in human and animal hosts using polymerase chain reaction and DNA sequencing

Enteromonas hominis, a human intestinal protozoan parasite of the diplomonad group, has been overlooked because of its commensal features; therefore, molecular studies on this parasite are limited. To address this gap, we designed a molecular screening protocol using polymerase chain reaction (PCR) and DNA sequencing targeting the 18S small subunit ribosomal RNA gene and applied this screening method to the molecular epidemiological analysis of Enteromonas spp. in humans and various livestock. We validated our methodology using stool samples collected from 215 humans and 270 animal hosts (buffaloes, pigs, dogs, goats, horses, rodents, chickens, and ducks) during an annual epidemiological investigation conducted from 2013 to 2016 on Sumba Island, Indonesia. The overall prevalences of Enteromonas spp. were 33.9% (n = 73/215) in humans and 25.2% (n = 68/270) in mammals and avians. The positive predictive value of this PCR method for Enteromonas spp., as evaluated through sequencing, was 90.1% in human samples and 58.1% in non-human samples (particularly low, 11.4% in rodents). Although the specificity of the PCR approach may not be perfect, in combination with DNA sequencing, it was effective in detecting and identifying a partial sequence (1,458 bp) of the target gene region in Enteromonas species.

Prevalence of intestinal protozoan parasites among Asian schoolchildren: a systematic review and meta-analysis.

Intestinal protozoan parasites among Asian schoolchildren are a subject of concern due to their prevalence and potential health impact. Understanding and addressing this issue is crucial for public health in the region. We conducted a comprehensive search for articles published up to December 2023 across four databases, including Scopus, PubMed, ProQuest, and Web of Science. To estimate the combined prevalence, a random-effects model with a 95% confidence interval (CI) was applied, and the statistical analysis was performed using meta-analysis packages in R version (3.6.1). This study is registered with PROSPERO (CRD42023481146). Among 131 eligible articles, the prevalence of intestinal protozoan parasites was 0.208 (95% CI = 0.180-0.238). Lebanon and Tajikistan had the highest country-level prevalence at 0.851 and 0.836, respectively, with Giardia duodenalis being the most prevalent species at 0.082. In summary, our study highlights the urgent public health issue of protozoan parasites among Asian schoolchildren due to poor sanitation and water quality. Immediate interventions are essential, considering climate and socioeconomic factors, to combat these infections and improve overall health.

Prevalence of intestinal protozoan parasites among Asian schoolchildren: a systematic review and meta-analysis.

Intestinal protozoan parasites among Asian schoolchildren are a subject of concern due to their prevalence and potential health impact. Understanding and addressing this issue is crucial for public health in the region. We conducted a comprehensive search for articles published up to December 2023 across four databases, including Scopus, PubMed, ProQuest, and Web of Science. To estimate the combined prevalence, a random-effects model with a 95% confidence interval (CI) was applied, and the statistical analysis was performed using meta-analysis packages in R version (3.6.1). This study is registered with PROSPERO (CRD42023481146). Among 131 eligible articles, the prevalence of intestinal protozoan parasites was 0.208 (95% CI = 0.180-0.238). Lebanon and Tajikistan had the highest country-level prevalence at 0.851 and 0.836, respectively, with Giardia duodenalis being the most prevalent species at 0.082. In summary, our study highlights the urgent public health issue of protozoan parasites among Asian schoolchildren due to poor sanitation and water quality. Immediate interventions are essential, considering climate and socioeconomic factors, to combat these infections and improve overall health.

PREVALENCE OF ECTO AND ENDO PARASITES OF WHITE CATFISH (AMEIURUS CATUS) IN UKE RIVER, KARU LOCAL GOVERNMENT AREA OF NASARAWA STATE, NIGERIA

In Uke River, Karu Local Government Area, Nasarawa State, Nigeria, a six-month research was carried out between January and June 2023 to examine the gills and intestinal helminth and protozoan parasites of White Catfish (Ameiurus catus). A total of 100 fresh Ameiurus catus fish samples of both sexes, were obtained from the fishermen and conveyed to the Zoology laboratory of Nasarawa State University for examination. The fishes were processed and examined using gills, oesophagus, intestine and rectum. Twenty-two (22) out of 100 fishes were found to be infected with helminth and protozoan parasites and a total of 31 parasites were isolated belonging to protozoa (Eimeria spp, Hexamita spp, Protoopalina spp), nematode (Procamallanus spp), trematode (Dactylogyrus spp), Cestode (Diphyllobothrium latum, Bothriocephalus claviceps) taxonomic groups. The findings indicated that Ameiurus catus intestine contained a greater quantity of fish parasites (96%). A nematode (Procamallanus spp.) was found to have the highest prevalence of 45.16%. Although the Chi square results showed no significant difference (p>0.05), the prevalence in Ameiurus catus was greater in female samples (63.64%) compared to male samples (36.36%). Fish weighing between 151-200 g (46.14%) and measuring between 21-30 cm (28.57%) had the highest percentage of parasite infection. Going forward, it is imperative to properly cook Ameiurus catus from the Uke River to prevent the spread of parasites to consumers. Additionally, it is advisable to steer clear of any potential actions that could contribute to the parasite predominance near the water body.

Alleviating Pentatrichomonas hominis-induced damage in IPEC-J2 cells: the beneficial influence of porcine-derived lactobacilli.

Pentatrichomonas hominis is a common intestinal parasitic protozoan that causes abdominal pain and diarrhea, and poses a zoonotic risk. Probiotics, known for enhancing immunity and pathogen resistance, hold promise in combating parasitic infections. This study aimed to evaluate two porcine-derived probiotics, Lactobacillus reuteri LR1 and Lactobacillus plantarum LP1, against P. hominis infections in pigs. Taxonomic identity was confirmed through 16S rRNA gene sequencing, with L. reuteri LR1 belonging to L. reuteri species and L. plantarum LP1 belonging to L. plantarum species. Both probiotics exhibited robust in vitro growth performance. Co-culturing intestinal porcine epithelial cell line (IPEC-J2) with these probiotics significantly improved cell viability compared with the control group. Pre-incubation probiotics significantly enhanced the mRNA expression of anti-oxidative response genes in IPEC-J2 cells compared with the PHGD group, with L. reuteri LR1 and L. plantarum LP1 significantly up-regulating CuZn-SOD、CAT and Mn-SOD genes expression (p < 0.05). The anti-oxidative stress effect of L. reuteri LR1 was significantly better than that of L. plantarum LP1 (p < 0.05). Furthermore, pre-incubation with the probiotics alleviated the P. hominis-induced inflammatory response. L. reuteri LR1 and L. plantarum LP1 significantly down-regulated IL-6、IL-8 and TNF-α gene expression(p < 0.05) compared with the PHGD group. The probiotics also mitigated P. hominis-induced apoptosis. L. reuteri LR1 and L. plantarum LP1 significantly down-regulated Caspase3 and Bax gene expression (p < 0.05), significantly up-regulated Bcl-2 gene expression (p < 0.05) compared with the PHGD group. Among them, L. plantarum LP1 showed better anti-apoptotic effect. These findings highlight the probiotics for mitigating P. hominis infections in pigs. Their ability to enhance anti-oxidative responses, alleviate inflammation, and inhibit apoptosis holds promise for therapeutic applications. Simultaneously, probiotics can actively contribute to inhibiting trichomonal infections, offering a novel approach for preventing and treating diseases such as P. hominis. Further in vivo studies are required to validate these results and explore their potential in animal and human health.

Genetic Diversity of Blastocystis in Diarrheal Cases: Identification of Subtypes and Alleles

Blastocystis spp. are the most common intestinal protozoan parasites detected in human stool samples. While identified long before today, its pathogenicity remains controversial. It is generally asymptomatic but in symptomatic cases, many gastrointestinal symptoms, especially diarrhea, have been associated with Blastocystis infection. In recent years, the relationship between the symptoms observed in cases and Blastocystis subtypes (ST) has been reported. The aim of this study was to detect Blastocystis in diarrheal cases admitted to the Aydın Adnan Menderes University Faculty of Medicine, Department of Parasitology Laboratory, to determine subtypes and allele diversity and to investigate its relationship with clinical symptoms. For this purpose, diarrheal stool samples of 200 cases were included in the study and their demographic characteristics (age, gender, residence) and clinical findings (abdominal pain, dyspepsia, nausea-vomiting, weakness, weight loss, anal itching, rash, urticaria) were recorded. Blastocystis was detected by direct microscope method (DM) and by molecular analyses which were performed with polymerase chain reaction (PCR). Subtype diversity was determined based on DNA sequence analysis by PCR targeting the Blastocystis ribosomal ribonucleic acid small subunit (SSU rRNA) gene. In addition, alleles related to Blastocystis subtypes were determined and statistically compared between all data and clinical findings. In the current study, Blastocystis was detected in 31 (15.5%) samples by DM and in 35 (17.5%) samples by PCR specific to the Blastocystis SSU rRNA gene among 200 diarrheal stool samples. No statistical difference was detected between Blastocystis and demographic characteristics. Dyspepsia and nausea-vomiting symptoms differed significantly in cases with Blastocystis compared to negative ones (p= 0.0025, p= 0.0498). Blastocystis subtype was detected in 33 samples by SSU rRNA sequence analysis, and the subtype distribution was ST1 (n= 10, 30.3%), ST2 (n= 4, 12.1%) and ST3 (n= 19, 57.6%). In the statistical evaluation between clinical findings and Blastocystis subtypes, a relationship was found between dyspepsia and Blastocystis ST3 (p= 0.0039). The allele diversity of Blastocystis subtypes was determined as allele 4 (10/10) in all ST1, allele 11 (2/4) and 12 (2/4) in ST2, allele 34 (14/19), 36 (4/19), and 38 (1/19) in ST3. In conclusion, our study provides important data on the molecular epidemiological characteristics of the Blastocystis by determining positivity, subtypes and alleles in diarrheal cases. Therefore, within the scope of the one health approach, comprehensive molecular epidemiological studies are required to determine the presence and genotypes of Blastocystis in human, animal and environmental samples.

First report of Giardia duodenalis in dairy cattle and beef cattle in Shanxi, China.

Giardia duodenalis is an important intestinal parasitic protozoan that infects several vertebrates, including humans. Cattle are considered the major source of giardiasis outbreak in humans. This study aimed to investigate the prevalence and multilocus genotype (MLG) of G. duodenalis in Shanxi, and lay the foundation for the prevention and control of Giardiosis. DNA extraction, nested polymerase chain reaction, sequence analysis, MLG analysis, and statistical analysis were performed using 858 bovine fecal samples from Shanxi based on three gene loci: β-giardin (bg), glutamate dehydrogenase (gdh), and triosephosphate isomerase (tpi). The overall prevalence of G. duodenalis was 28.3%, while its prevalence in Yingxian and Lingqiu was 28.1% and 28.5%, respectively. The overall prevalence of G. duodenalis in dairy cattle and beef cattle was 28.0% and 28.5%, respectively. G. duodenalis infection was detected in all age groups evaluated in this study. The overall prevalence of G. duodenalis in diarrhea and nondiarrhea samples was 32.4% and 27.5%, respectively, whereas that in intensively farmed and free-range cattle was 35.0% and 19.9%, respectively. We obtained 83, 53, and 59 sequences of bg, gdh, and tpi in G. duodenalis, respectively. Moreover, assemblage A (n = 2) and assemblage E (n = 81) by bg, assemblage A (n = 1) and assemblage E (n = 52) by gdh, and assemblage A (n = 2) and assemblage E (n = 57) by tpi were identified. Multilocus genotyping yielded 29 assemblage E MLGs, which formed 10 subgroups. To the best of our knowledge, this is the first study to report cattle infected with G. duodenalis in Shanxi, China. Livestock-specific G. duodenalis assemblage E was the dominant assemblage genotype, and zoonotic sub-assemblage AI was also detected in this region.

Modified trichrome stain for faster and improved detection of intestinal protozoan parasites.

Permanent stains such as trichrome have better sensitivity but are time-consuming and the fixative includes toxic mercuric chloride. Thus, a newer modification was tested and found to be a superior, faster and safer staining technique for intestinal parasitic detection. Our study lasted 9 months and a single stool sample was collected from each enrolled patient. We evaluated classical trichrome (T1 - using Schaudinn fixative) with newer modifications, which involved different fixatives with mordant combinations (T2 - acetic acid + hydrated aluminium sulphate, T3 - citric acid + copper sulphate hydrate). Conventional PCR targeting Entamoeba histolytica, Giardia lamblia and Cryptosporidium spp. was taken as the reference. Out of 175 stool samples, 25.1% protozoa were identified by wet mount, 24% by each T1 and T2, 25.7% by T3. Statistically, T3 and T2 had higher sensitivity as compared to T1 and wet mount when PCR was used as reference.

Entamoeba histolytica Infection in the Philippines: A Review

Entamoeba histolytica, an intestinal protozoan parasite, is the primary causative agent of both intestinal and extraintestinal amoebiasis. While six species of Entamoeba have been identified in the human gut, only E. histolytica is well recognized as a pathogenic amoeba associated with intestinal and extraintestinal infections. In many cases of E. histolytica infection, symptoms are either absent or mild, whereas the most frequent clinical manifestations are colitis and liver abscess due to amoebic infection. Diagnosis typically relies on microscopic and serological methods. Metronidazole is the standard therapy for treating children and adults with invasive amoebiasis. However, the absence of an effective vaccine poses a significant challenge to controlling the transmission and progression of the parasite into an active, invasive disease. Notably, in developing tropical countries like the Philippines, significant cases of E. histolytica infections have been documented in communities with inadequate sanitation and hygiene practices. The development of pragmatic and cost-effective diagnostic methods is therefore crucial for the clinical care of amoebiasis patients. Drawing from a limited pool of published articles (2010 to date) on cases of E. histolytica infections and parasitological surveys in the Philippines, the current review underscores the critical knowledge gap on the prevalence of amoebiasis as well as the disease pathology and treatment of this zoonotic parasitic disease.

Cryptosporidium species and subtypes identified in human domestic cases through the national microbiological surveillance programme in Sweden from 2018 to 2022

BackgroundThe intestinal protozoan parasite Cryptosporidium is an important cause of diarrheal disease worldwide. A national microbiological surveillance programme was implemented in Sweden in 2018 in order to increase knowledge of the molecular epidemiology of human cryptosporidiosis to better understand transmission patterns and potential zoonotic sources. This article summarises the results of the first five years of the surveillance programme.MethodsCryptosporidium-positive faecal and DNA samples from domestically acquired infections were collected from clinical microbiological laboratories in Sweden. Species and subtype determination was performed using 60 kDa glycoprotein and/or small subunit ribosomal RNA gene analysis.ResultsBetween 2018 and 2022, 1654 samples were analysed and 11 different species were identified: C. parvum (n = 1412), C. mortiferum (n = 59), C. hominis (n = 56), C. erinacei (n = 11), C. cuniculus (n = 5), C. meleagridis (n = 3), C. equi (n = 2), C. ubiquitum (n = 2), and one each of C. canis, C. ditrichi and C. felis. Subtyping revealed seven subtype families of C. parvum (new subtype families IIy and IIz) and 69 different subtypes (11 new subtypes). The most common C. parvum subtypes were IIdA22G1c, IIdA24G1, IIdA15G2R1 and IIaA16G1R1b. For C. hominis, four different subtype families and nine different subtypes (two new subtypes) were identified. For additional species, two new subtype families (IIIk and VId) and nine new subtypes were identified. All successfully subtyped C. mortiferum cases were subtype XIVaA20G2T1, confirming previous findings in Sweden. Several outbreaks were identified of which the majority were foodborne and a few were due to direct contact with infected animals.ConclusionInfection with C. parvum is the leading cause of human cryptosporidiosis acquired in Sweden, where more than 90% of domestic cases are caused by this zoonotic species and only a small proportion of cases are due to infection with other species. The rodent-associated C. mortiferum is considered an emerging zoonotic species in Sweden and the number of domestically acquired human cases has surpassed that of infection with C. hominis. A high diversity of species and subtypes, as well as diversity within the same subtype, was detected. Also, cryptosporidiosis appears to affect adults to a great extent in Sweden.

Preliminary investigations of parasite contamination of water sources in Armenia

The intestinal protozoan parasites, Cryptosporidium and Giardia, are known to have a global distribution, infecting and causing disease in a range of hosts, including people, livestock, pets, and wildlife. However, data from some regions is very sparse. In Armenia, in the Caucasus region of West Asia, only scanty data are available, with just a few surveys on Cryptosporidium infections in livestock, and no available data on human infections or environmental contamination. As part of implementation of water analysis methods for these parasites in Armenia, 24 raw water samples and two sediment samples were analysed for these parasites using a range of approaches, including modified Ziehl-Neelsen, Lugol stain, immunofluorescent antibody test (IFAT), qPCR and, on sediment samples, immunomagnetic separation and IFAT. Results suggest substantial contamination of raw water sources and indicate the need for further targeted studies using appropriate methods and collecting data on host infections in catchment areas.

Intestinal Protozoans among HIV Patients in a Rural Setting, Southern Nigeria

Opportunistic parasitic protozoan infections in HIV infected patients remain a worldwide public health concern. A cross sectional study on HIV patients was carried out in some parts of Imo State with a view of assessing the prevalence of intestinal protozoan parasites. Stool samples were collected and analysed applying standard techniques. Overall, four species of protozoan parasites were isolated namely, C.parvum, E.histolytica, G.lamblia and Ent. coli. Total prevalence is highest (52.2%) amongst the age group of ≤27 years, followed by 45-48years(27.8%) while the least prevalence(11.8%) is recorded for the age group of 49 years and above. More female (26.3%) were infected than male (25.4%). Significant association between age and protozoan prevalencewas noted(p-value=0.007; X2=32.998a, df=16). Further analysis selecting Cramer’s V which is the measure of association based on chi-square shows a weak dependence between age and parasite prevalence (Cramer’s V-value = 0.286). Pearson correlation shows a positive, weak (R=0.170; sig.=0.089c) relationship between age and protozoan parasite prevalence. Test of association between gender and intestinal protozoan parasites shows a non-significant association(p=0.280;X2=5.069a), weak dependence(Cramer’s V-value = 0.280) and a negative, weak relationship between gender and parasite prevalence(R=-0.042; sig=0.674c). Subjects with CD4count &lt;200µ/ml recorded the highest(40.0%) prevalence of intestinal protozoan parasite while 200-349µ/ml recorded the least prevalence(4.0%).Significant association exists between CD4 count and parasite prevalence(x2=53.9a, df=12,p=0.001);then Cramer’s v test shows a medium-strong dependence. High prevalence (37.0%) of intestinal protozoan parasites is recorded for subjects not on HAART while low prevalence (12.8%) is recorded for those on HAART; with Significant association (x2=16.157a, df=4, p=0.003) and medium-strong dependence (Cramer’s v =0.40).The result of this study shows that intestinal parasites are of public health concern among immunocompromised individuals and calls for urgent attention of relevant stakeholders

Prevalence and assemblage of Giardia duodenalis in a case-control study of children under 5 years from Jimma, Southwest Ethiopia

Giardia duodenalis is a common pathogenic intestinal protozoan parasite with high prevalence in developing countries, especially among children. The distribution of giardia assemblages among humans and their clinical relevance remains controversial. This study aimed to determine the prevalence and assemblage of Giardia among children under 5 years of age in Jimma, Southwest Ethiopia. Employing a case-control design, 606 children presenting with diarrhea at Jimma university medical center and Serbo Health Center were enrolled from December 2016 to July 2018 along with 617 matched controls without diarrhea. Giardia was detected and typed using real-time PCR. Univariate and multivariate regression analysis was performed. The total prevalence of Giardia was 41% (501/1223) and did not differ significantly between cases and controls (40% vs 42%). Prevalence increased by age, with the highest prevalence seen in children aged ≥ 25 months. Children without diarrhea with a history of diarrhea during the last month were more likely to be Giardia positive compared to children with no history diarrhea (OR 1.8 and 95%CI; 1.1–2.9). Regardless of current diarrhea symptoms, assemblage B predominated with 89%, followed by assemblage A (8%) and mixed infection assemblage A and B (3%). We report a high prevalence of Giardia by PCR detection in Jimma, Ethiopia, with assemblage B being predominant. There was a similar distribution of Giardia assemblages between children with and without diarrhea. Increasing age was a risk factor for Giardia infection. Community-based prevention and control strategies need to be employed to decrease the risk of giardia infection.

First Detection of Cryptosporidium parvum in the Endemic Cyprus Mouflon (Ovisgmelini ophion).

Cryptosporidiumis an intestinal zoonotic protozoan parasite that infects domesticated and wild animals. There are no reports on the prevalence and molecular characterisation ofCryptosporidiumin the endemic Cyprus mouflon. The mouflon is strictly protected by national and international legislation. Its main distribution is Paphos State Forest and surrounding areas, where it may share the same water sources as free-ranging domestic goats. Therefore, the present study aimed to determine the prevalence ofCryptosporidiumspp. and genotypes in mouflon and free-ranging goats within the mouflon range. Faecal samples of 70 mouflons and 34 free-ranging goats were screened forCryptosporidiumby PCR amplification and sequencing. Only one sample (1/70) belonging to a mouflon was PCR positive forCryptosporidium. Based on sequencing of the18SrRNA locus, this species was identified asCryptosporidium parvum (C. parvum). No positive sample was detected in the free-ranging goats (0/34). This is the first report on the molecular identification of thisCryptosporidiumspecies in a Cyprus mouflon. The results indicate that the prevalence of Cryptosporidium in Cyprus mouflon is low.

Prevalence and sequence diversity of Balantioides coli in pigs in Xinjiang, China.

Balantioides coli is a common intestinal parasitic protozoan in pigs. In the present study, 801 fecal samples of pigs from seven farms in Xinjiang were analyzed based on the ITS1-5.8S rRNA-ITS2 gene. The prevalence of B. coli was 4.2% (34/801), with the highest prevalence of 18.9% (18/95) occurring in Alaer, Xinjiang. B. coli was detected in all age groups (pre-weaned pigs, post-weaned pigs, fattening pigs and sows), with the highest rate in fatteners (6.9%, 9/129) and the lowest (1.2%, 2/169) in pre-weaned pigs. Significant differences (P = 0.000) were found among sampling sites but not among age groups (P = 0.084). Sequence analysis indicated that 34 sequence variants, including sequence type A (n = 11) and sequence type B (n = 23), occurred in all age groups. In this study, the existence of sequence type A suggested that B. coli poses a potential threat to human health. More studies are needed to better understand the distributions and public health significance of B. coli in China.

On the occurrence of a glutaredoxin-like small protein in the anaerobic protozoan parasite Entamoeba histolytica

BackgroundEntamoeba histolytica, an intestinal parasitic protozoan that usually lives and multiplies within the human gut, is the causative agent of amoebiasis. To date, de novo glutathione biosynthesis and its associated enzymes have not been identified in the parasite. Cysteine has been proposed to be the main intracellular thiol. MethodsUsing bioinformatics tools to search for glutaredoxin homologs in the E. histolytica genome database, we identified a coding sequence for a putative Grx-like small protein (EhGLSP) in the E. histolytica HM-1:IMSS genome. We produced the recombinant protein and performed its biochemical characterization. ResultsThrough in vitro experiments, we observed that recombinant EhGLSP could bind GSH and L-Cys as ligands. However, the protein exhibited very low GSH-dependent disulfide reductase activity. Interestingly, via UV–Vis spectroscopy and chemical analysis, we detected that recombinant EhGLSP (freshly purified from Escherichia coli cells by IMAC) was isolated together with a redox-labile [FeS] bio-inorganic complex, suggesting that this protein could have some function linked to the metabolism of this cofactor. Western blotting showed that EhGLSP protein levels were modulated in E. histolytica cells exposed to exogenous oxidative species and metronidazole, suggesting that this protein cooperates with the antioxidant mechanisms of this parasite. Conclusions and general significanceOur findings support the existence of a new metabolic actor in this pathogen. To the best of our knowledge, this is the first report on this protein class in E. histolytica.

Molecular screening of Entamoeba spp. (E. histolytica, E. dispar, E. coli, and E. hartmanni) and Giardia intestinalis using PCR and sequencing

A wide range of intestinal protozoan parasites inhabit the human gut. To establish a more comprehensive molecular screening, we designed PCR-sequencing screening methods for Entamoeba spp., including commensal species, and Giardia intestinalis, and performed such methods using 174 stool samples collected from Kenyan children. The prevalences of the target species were as follows: E. histolytica (2/174, 1.1%), E. dispar (20/174, 11.5%), E. coli (107/174, 61.5%), E. hartmanni (77/174, 44.3%), and G. intestinalis (54/174, 31.0%). PCR amplicons specific to G. intestinalis was differentiated to assemblages A (8/174, 4.6%) and B (46/174, 26.4%). PCR specificity for Entamoeba spp. was quite high, except for some cross-reactions between E. hartmanni detection primers and G. intestinalis, although the false-positive amplicons were discernible by the band size. The 18S rRNA PCR primers that was designed by Monis et al. in 1999 for G. intestinalis, have specificity issue, therefore amplicon sequencing was essential not only to determine assemblage classifications but also to confirm the positive results by eliminating potential non-specific reactions. The detection sensitivity of both the Entamoeba universal PCR and the G. intestinalis PCR was more than 100 copies of the target loci, which is sufficient for detecting a single trophozoite or cyst of both species.

Metagenomic analysis reveals the relationship between intestinal protozoan parasites and the intestinal microecological balance in calves

BackgroundA close connection between a protozoan parasite and the balance of the other gut microbes of the host has been demonstrated. The calves may be naturally co-infected with many parasites, and the co-effects of parasites on other intestinal microbes of calves remain unclear. This study aims to preliminarily reveal the relationship between intestinal parasites and other intestinal microbes in calves.MethodsFecal samples were collected from four calves with bloody diarrhea, four calves with watery diarrhea, and seven normal calves, and the microbial flora of the samples were analyzed by whole-genome sequencing. Protozoal parasites were detected in the metagenome sequences and identified using polymerase chain reaction (PCR).ResultsCryptosporidium, Eimeria, Giardia, Blastocystis, and Entamoeba were detected by metagenomic analysis, and the identified species were Giardia duodenalis assemblage E, Cryptosporidium bovis, Cryptosporidium ryanae, Eimeria bovis, Eimeria subspherica, Entamoeba bovis, and Blastocystis ST2 and ST10. Metagenomic analysis showed that the intestinal microbes of calves with diarrhea were disordered, especially in calves with bloody diarrhea. Furthermore, different parasites show distinct relationships with the intestinal microecology. Cryptosporidium, Eimeria, and Giardia were negatively correlated with various intestinal bacteria but positively correlated with some fungi. However, Blastocystis and Entamoeba were positively associated with other gut microbes. Twenty-seven biomarkers not only were significantly enriched in bloody diarrhea, watery diarrhea, and normal calves but were also associated with Eimeria, Cryptosporidium, and Giardia. Only Eimeria showed a distinct relationship with seven genera of bacteria, which were significantly enriched in the healthy calves. All 18 genera of fungi were positively correlated with Cryptosporidium, Eimeria, and Giardia, which were also significantly enriched in calves with bloody diarrhea. Functional genes related to parasites and diseases were found mainly in fungi.ConclusionsThis study revealed the relationship between intestinal protozoan parasites and the other calf gut microbiome. Different intestinal protozoan parasites have diametrically opposite effects on other gut microecology, which not only affects bacteria in the gut, but also is significantly related to fungi and archaea.Graphical

The nucleolus of Giardia and its ribosomal biogenesis.

Giardia duodenalis is a protozoan intestinal parasite that causes a significant number of infections worldwide each year, particularly in low-income and developing countries. Despite the availability of treatments for this parasitic infection, treatment failures are alarmingly common. As a result, new therapeutic strategies are urgently needed to effectively combat this disease. On the other hand, within the eukaryotic nucleus, the nucleolus stands out as the most prominent structure. It plays a crucial role in coordinating ribosome biogenesis and is involved in vital processes such as maintaining genome stability, regulating cell cycle progression, controlling cell senescence, and responding to stress. Given its significance, the nucleolus presents itself as a valuable target for selectively inducing cell death in undesirable cells, making it a potential avenue for anti-Giardia treatments. Despite its potential importance, the Giardia nucleolus remains poorly studied and often overlooked. In light of this, the objective of this study is to provide a detailed molecular description of the structure and function of the Giardia nucleolus, with a primary focus on its involvement in ribosomal biogenesis. Likewise, it discusses the targeting of the Giardia nucleolus as a therapeutic strategy, its feasibility, and the challenges involved.

Prevalence of Intestinal Protozoa in Pigs of Northern Black Sea Region, Ukraine

Intestinal protozoan parasites threaten the health and welfare of pigs and impair the sustainability of pig farms, resulting in monetary losses. The present study aimed to determine the distribution of protozoa in large white pigs in the farms of Odesa, Mykolaiv, and Kherson regions in Ukraine. The parasitological surveys were conducted from March 2020 to March 2022 on three types of farms, including four large farms (&gt; 100 sows), six medium farms (25-100 sows), and eight small farms (&lt; 25 sows). A total of 3938 fecal samples from pigs of various age groups, namely 0-2-month piglets, 2-4-month piglets, pigs on fattening, and sows, were examined. Eimeria and isospores were determined using McMaster’s method in Raynaud’s modification, cryptosporidia by staining smears, blastocysts by the method of ethyl acetate-formalin concentration, and direct microscopy. The recorded protozoa were species Eimeria spp., Cystoisospora suis (syn. Isospora suis), Balantidium coli, Cryptosporidium spp., Blastocystis spp. These species of protozoa were observed in 31.1%, 49.0%, and 58.8% of pigs in large, medium-sized, and small farms, respectively. The findings indicated that Isospora suis and Eimeria spp. were most commonly present in piglets aged 0-2 months in large (29.7% and 23.0%, respectively), medium (32.3%, 29.4%), and small farms (30.0%, 13.5%). Balantidium coli was not registered in pigs from large farms, and in piglets 2-4 months old from small farms, the prevalence of infestation was 17.2%. Cryptosporidium spp. and Blastocystis spp. were mostly recorded in piglets 2-4 months old from small farms (16.2%, 7.1%). In large and medium-sized farms of the Northern Black Sea region, mono infestations were recorded the most (73.6%, 72.0%), while mixed two-component infestation dominated (52.5%) small farms. Intestinal protozoa should be considered in the differential diagnosis of intestinal disorders as major factors or concomitant intestinal pathogens.