The indelible toll of enteric pathogens: Prevalence, clinical characterization, and seasonal trends in patients with acute community-acquired diarrhea in disenfranchised communities.

BACKGROUND: There is little information on the epidemiology of enteric pathogens in Lebanon, a low- and middle-income country that suffers from a myriad of public health challenges. To address this knowledge gap, we aimed to assess the prevalence of enteric pathogens, identify risk factors and seasonal variations, and describe associations between pathogens among diarrheic patients in the Lebanese community. METHODOLOGY AND PRINCIPAL FINDINGS: A multicenter cross-sectional community-based study was conducted in the north of Lebanon. Stool samples were collected from 360 outpatients suffering from acute diarrhea. Based on fecal examination using the BioFire® FilmArray® Gastrointestinal Panel assay, the overall prevalence of enteric infections was 86.1%. Enteroaggregative Escherichia coli (EAEC) was the most frequently identified (41.7%), followed by enteropathogenic E. coli (EPEC) (40.8%) and rotavirus A (27.5%). Notably, two cases of Vibrio cholerae were identified, while Cryptosporidium spp. (6.9%) was the most common parasitic agent. Overall, 27.7% (86/310) of the cases were single infections, and the majority, 73.3% (224/310), were mixed infections. Multivariable logistic regression models showed that enterotoxigenic E. coli (ETEC) and rotavirus A infections were significantly more likely to occur in the fall and winter compared to the summer. Rotavirus A infections significantly decreased with age but increased in patients living in rural areas or suffering from vomiting. We identified strong associations in the co-occurrence of EAEC, EPEC, and ETEC infections and a higher percentage of rotavirus A and norovirus GI/GII infections among EAEC-positive cases. CONCLUSIONS: Several of the enteric pathogens reported in this study are not routinely tested in Lebanese clinical laboratories. However, anecdotal evidence suggests that diarrheal diseases are on the rise due to widespread pollution and the deterioration of the economy. Therefore, this study is of paramount importance to identify circulating etiologic agents and prioritize dwindling resources to control them and limit outbreaks in the future.

Intestine microbiota and SCFAs response in naturally Cryptosporidium-infected plateau yaks.

Diarrhea is a severe bovine disease, globally prevalent in farm animals with a decrease in milk production and a low fertility rate. Cryptosporidium spp. are important zoonotic agents of bovine diarrhea. However, little is known about microbiota and short-chain fatty acids (SCFAs) changes in yaks infected with Cryptosporidium spp. Therefore, we performed 16S rRNA sequencing and detected the concentrations of SCFAs in Cryptosporidium-infected yaks. Results showed that over 80,000 raw and 70,000 filtered sequences were prevalent in yak samples. Shannon (p<0.01) and Simpson (p<0.01) were both significantly higher in Cryptosporidium-infected yaks. A total of 1072 amplicon sequence variants were shared in healthy and infected yaks. There were 11 phyla and 58 genera that differ significantly between the two yak groups. A total of 235 enzymes with a significant difference in abundance (p<0.001) were found between healthy and infected yaks. KEGG L3 analysis discovered that the abundance of 43 pathways was significantly higher, while 49 pathways were significantly lower in Cryptosporidium-infected yaks. The concentration of acetic acid (p<0.05), propionic acid (p<0.05), isobutyric acid (p<0.05), butyric acid (p<0.05), and isovaleric acid was noticeably lower in infected yaks, respectively. The findings of the study revealed that Cryptosporidium infection causes gut dysbiosis and results in a significant drop in the SCFAs concentrations in yaks with severe diarrhea, which may give new insights regarding the prevention and treatment of diarrhea in livestock.

Microbial bowel infections-induced biochemical and biological abnormalities and their effects on young Egyptian swimmers.

Swimmers' personal hygiene affects the spread of microbes in pools. The present study aimed to determine the incidence of microbial infections among young Egyptian swimmers and its impact on swimmers' scores. From January 2020 to June 2021, 528 public club swimmers were examined cross-sectionally. Swimmers were divided into two groups according to their star tests and their scores in the competition (group 1 with a high score and group 2 with a low score). Stool samples, biochemical and biological parameters were assessed. Microbial infections were 54% for intestinal parasitosis and 2.8% for Helicobacter pylori. The rate of intestinal parasitosis was higher among Gp2 as compared to Gp1. The results also revealed higher prevalence of Cryptosporidium spp., Giardia lamblia, Entameba histolytica, and Cyclospora among Gp2 than Gp1. Swimming frequency, and duration influenced the infectious status that induced anemia, abnormal blood pressure, and heart rate. Infected swimmers with cryptosporidiosis had higher alanine transaminase levels, white blood cells, and differential cells but lower aspartate transaminase levels. Giardiasis showed higher reduction in the biochemical markers including ferritin, lactoferrin, iron, and transferrin among Gp 2, compared to Gp 1 and thus affected the swimmers' scores. Thus, raising swimmers' hygiene awareness and targeting health education is obliged.

Prevalence and molecular analysis of Cryptosporidium spp. collected from surface water.

Cryptosporidium is an obligate intracellular parasite reported from all over the world. This protozoan infects a wide range of animals as well as humans. Cryptosporidium parvum and Cryptosporidium hominis are the most prevalent infecting species with mild and self-limiting infection in healthy people. The protozoan oocyst is resistant to common water purifiers. Based on emerging evidence, Cryptosporidium is one of waterborne parasites considered a major public health problem in developing and developed countries. In this study, 42 samples were collected from 14 rivers in the catchment area of Lake Urmia in northwest of Iran. Moreover, amplification of SSU rRNA gene was performed, and polymerase chain reaction products were sequenced. The results of sequencing and comparing the sequences with those in the GenBank revealed that all the 17 positive samples were C. parvum, a zoonotic species and one of the most frequent human-infecting species. Considering these data, it is highly important to inhibit the spread of this protozoan by treating livestock and preventing human and animal effluents from entering the water.

A Cross-Sectional Survey of Gastrointestinal Parasites in an Ornithological Garden.

Captive birds in collections may be infested with a wide range of parasites. Globally, information on parasitic infections and their health implications in ornithological collections are scarce. In the present study, the prevalence of parasitic infections in an ornithological garden in Tehran was investigated. Samples (n = 109) from various bird species were collected. Direct wet smear, sedimentation, flotation with Sheather's sugar, and modified Ziehl-Neelsen and Giemsa staining were used for parasite screening. Parasites were identified in 57 (52.3%, 95% confidence interval [CI] 42.9-61.7) samples, with protozoans being the most frequently observed organisms, including Cryptosporidium species, Eimeria species, Isospora species, Trichomonas species, and Histomonas species. Helminths were observed in 29 (26.6%, 95% CI 18.3-34.9) of the samples and included strongyles, Capillaria species, and Raillietina species. Ectoparasites were rarely recovered, but 2 species were identified: the poultry shaft louse (Menopon gallinae) and the fowl tick (Argas persicus). Free-ranging birds were significantly (P < 0.001) more likely to have parasites in their feces than caged birds. Fecal parasitic infections were order dependent and more prevalent in the Anseriformes and Galliformes (P < 0.05). The frequency of gastrointestinal parasites was notable in the investigated collection. In open natural bird gardens, such as in the present study, the probable transmission routes and sources of the parasitic infections are most likely via the free-ranging avian species. It is wise to recommend regular screening of the birds in these gardens to improve preventive control measures. Additionally, parasite genotyping should be considered to clarify our understanding of the epidemiology of zoonotic and nonzoonotic parasites.

Molecular characterization of waterborne protozoa in surface water and sediment in Brazil: a taxonomic survey of ciliated protozoa and their correlation with Giardia duodenalis and Cryptosporidium spp.

The detection of Giardia duodenalis and Cryptosporidium spp. was performed, along with the identification of the ciliated protozoa biodiversity, to evaluate the correlation between these protozoa in freshwater quality monitoring. Water and sediment samples from two sites in the Atibaia River (Campinas, São Paulo, Brazil) were collected monthly for 2 years (n = 96). Pathogenic protozoa in water and sediment were detected by using immunomagnetic separation, followed by visualization by immunofluorescence assay (IFA). All positive aliquots in IFA were subjected to DNA extraction and subsequently nested PCR. Qualitative (in vivo observation and silver impregnation) and quantitative (in vivo enumeration) analyses were performed for the ciliated protozoa. Giardia cysts were detected in 62.5% of the surface water samples and Cryptosporidium spp. in 25.0%. In the sediment, cysts were detected in 35.4% samples and oocysts in 16.6%. A total of 57 samples positive for Giardia cysts were subjected to sequencing, 40 of which were harboring G. duodenalis (24 were characterized as sub-assemblage AII). For ciliated protozoa, 73 taxa belonging to 53 genera were identified over the period of the study. These results revealed a high degree of contamination by waterborne protozoa in the main water source which supplies drinking water for more than one million people in Campinas (São Paulo), highlighting the need for continuous monitoring of this catchment site. In addition, the present study provides important data regarding the sources of the water body degradation, i.e., fecal contamination of human origin, in addition to the survey of the ciliated protozoa.

Prevalence of Ecto and Gastrointestinal Parasites of Rattus rattus in Mazandaran Province, North of Iran

Objective: Rodents act as reservoir hosts and are an important potential source for many zoonotic pathogens such as parasites, which pose a public health risk to humans. Therefore, it is necessary to investigate the prevalence of parasites among rodents. Methods: A total of 118 Rattus rattus were captured in Mazandaran province, north of Iran, using snap live traps. Various samples were collected from feces and each rat was combed with a fine-tooth comb to extricate any ectoparasite. Fecal specimens were examined by direct wet mounting, formalin-ether concentration, modified acid-fast, and trichrome staining methods. Results: The overall prevalence of gastrointestinal parasites in the examined rats was 75.4%. Cryptosporidium spp. (30.5%) were the most prevalent protozoan, followed by Giardia spp. (20.3%), Entamoeba muris (13.5%), Trichomonas muris (10.1%), and Spironucleus muris (3.3%). Regarding helminths' eggs, Syphacia obvelata (24.5%), Hymenolepis diminuta (10.1%), and Trichuris muris (9.3%) had the highest prevalence, respectively. Furthermore, 3060 ectoparasites collected from 102 rodents were infested with lice (40% Polyplax spp.), mites (33.3%), and flea (16.1% Xenopsylla cheopis and 10.6% Xenopsylla astia). Conclusion: According to the results of this study, the prevalence of ecto and gastrointestinal parasites in the collected rats in the area being studied was remarkably high. Additionally, Rattus rattus can be considered a potential risk to human health.

Monitoring the Trends in Intestinal Parasite Frequencies; 2018 and 2022 Data

Objective: Monitoring intestinal parasite frequencies is effective on diagnosis, treatment, and prevention strategies to be developed against these parasites. In this study, it was aimed to reveal the parasite species and frequency data of stool samples in parasitology direct diagnosis laboratory. Methods: Stool parasitological examination results were obtained retrospectively from our laboratory internal quality control data tables. Data belonging to the year 2018 and 2022 were compared retrospectively. Results: Annual parasites detected in stool samples were 388 of 4.518, and 710 of 3.537, in 2018 and 2022, respectively. Frequency of parasite detection in stool samples was found to be significantly higher in 2022 (p<0.0001). Number of stools with more than one parasite was 12 and 30 in 2018 and 2022, respectively. Incidence of infection with more than one parasite was significantly higher in 2022 (p=0.0003). Five most common parasite species were Blastocystis spp., Enterobius vermicularis, Cryptosporidium spp., Giardia intestinalis and Entamoeba histolytica in 2018, respectively; and Cryptosporidium spp., Blastocystis spp., Cyclospora spp., Entamoeba dispar and Giardia intestinalis, in 2022, respectively. Cryptosporidium spp., Cyclospora spp. and Entamoeba dispar increased significantly, while Blastocystis spp. and Enterobius vermicularis decreased significantly, in 2022. Conclusion: According to the data obtained, causative agents for intestinal parasitic infections were protozoans, especially Cryptosporidium spp. It has been concluded that tightening the measures for protection of water with one health approach and improving the education and habits of society on personal hygiene and food safety can be effective in reducing the frequency of intestinal parasite infections in our region.

Cryptosporidium uses CSpV1 to activate host type I interferon and attenuate antiparasitic defenses.

Cryptosporidium infects gastrointestinal epithelium and is a leading cause of infectious diarrhea and diarrheal-related death in children worldwide. There are no vaccines and no fully effective therapy available for the infection. Type II and III interferon (IFN) responses are important determinants of susceptibility to infection but the role for type I IFN response remains obscure. Cryptosporidium parvum virus 1 (CSpV1) is a double-stranded RNA (dsRNA) virus harbored by Cryptosporidium spp. Here we show that intestinal epithelial conditional Ifnar1-/- mice (deficient in type I IFN receptor) are resistant to C. parvum infection. CSpV1-dsRNAs are delivered into host cells and trigger type I IFN response in infected cells. Whereas C. parvum infection attenuates epithelial response to IFN-γ, loss of type I IFN signaling or inhibition of CSpV1-dsRNA delivery can restore IFN-γ-mediated protective response. Our findings demonstrate that type I IFN signaling in intestinal epithelial cells is detrimental to intestinal anti-C. parvum defense and Cryptosporidium uses CSpV1 to activate type I IFN signaling to evade epithelial antiparasitic response.

Seasonal variation of diarrhoeal pathogens among Guinea-Bissauan children under five years of age.

BACKGROUND: Diarrhoea remains a major cause of childhood morbidity and mortality in low-income countries (LICs). The frequency of diarrhoeal episodes may vary by season, yet few prospective cohort studies have examined seasonal variation among various diarrhoeal pathogens using multiplex qPCR to analyse bacterial, viral and parasitic pathogens. METHODS: We combined our recent qPCR data of diarrhoeal pathogens (nine bacterial, five viral and four parasitic) among Guinea-Bissauan children under five years old with individual background data, dividing by season. The associations of season (dry winter and rainy summer) and the various pathogens were explored among infants (0-11 months) and young children (12-59 months) and those with and without diarrhoea. RESULTS: Many bacterial pathogens, especially EAEC, ETEC and Campylobacter, and parasitic Cryptosporidium, prevailed in the rainy season, whereas many viruses, particularly the adenovirus, astrovirus and rotavirus proved common in the dry season. Noroviruses were found constantly throughout the year. Seasonal variation was observed in both age groups. CONCLUSION: In childhood diarrhoea in a West African LIC, seasonal variation appears to favour EAEC, ETEC, and Cryptosporidium in the rainy and viral pathogens in the dry season.

Occurrence of enteric and non-enteric microorganisms in coastal waters impacted by anthropogenic activities: A multi-route QMRA for swimmers.

The purpose of this study was to evaluate the microbial characteristics of coastal waters which are impacted by anthropogenic pollution as well as estimate the health risks associated with exposure to enteric and non-enteric microorganisms during swimming. Fecal indicator bacteria were highly detected in samples. Moreover, pathogenic and opportunistic microorganisms were found, with the highest frequency for Pseudomonas aeruginosa followed by Adenovirus 40/41, Acanthamoeba spp., Salmonella enterica, and Cryptosporidium parvum. The median risk of gastrointestinal illness through ingestion of water was estimated to be above the benchmark value of 0.05 per event recommended by WHO. Cryptosporidium followed by Adenovirus, showed higher illness risks than Salmonella. The potential risks of Acanthamoeba and P. aeruginosa were estimated to be low for both dermal and ocular exposure routes. However, there are uncertainties about the infectious fraction of pathogens existing in coastal waters and the delivered dose of microorganisms from dermal/ocular exposure during recreational activities.

A systematic review of frequency and geographic distribution of water-borne parasites in the Middle East and North Africa.

Background: Water-borne parasitic infections are caused by pathogenic parasites found in water. These parasites are often not well-monitored or reported, therefore, there is an underestimation of their prevalence. Aims: We systemically reviewed the prevalence and epidemiology of water-borne diseases in the Middle East and North Africa (MENA) Region, which has a population of about 490 million people distributed over 20 independent countries. Methods: Online scientific databases, mainly PubMed, ScienceDirect, Scopus, Google Scholar, and MEDLINE were searched for the main water-borne parasitic infections in MENA countries during 1990-2021. Results: The main parasitic infections were cryptosporidiosis, amoebiasis, giardiasis, schistosomiasis, and toxocariasis. Cryptosporidiosis was the most frequently reported. Most of the published data were from Egypt, the country with the highest population in MENA. Conclusions: Water-borne parasites are still endemic in many MENA countries, however, their incidence has reduced dramatically due to the control and eradication programmes in countries that could afford such programmes, some with external support and funding.

Characterization of CpCaM, a protein potentially involved in the growth of Cryptosporidium parvum.

Cryptosporidium parvum is an important apicomplexan parasite causing severe diarrhea in both humans and animals. Calmodulin (CaM), a multifunctional and universal calcium-binding protein, contributes to the growth and development of apicomplexan parasites, but the role of CaM in C. parvum remains unknown. In this study, the CaM of C. parvum encoded by the cgd2_810 gene was expressed in Escherichia coli, and the biological functions of CpCaM were preliminarily investigated. The transcriptional level of the cgd2_810 gene peaked at 36 h post infection (pi), and the CpCaM protein was mainly located around the nucleus of the whole oocysts, in the middle of sporozoites and around the nucleus of merozoites. Anti-CpCaM antibody reduced the invasion of C. parvum sporozoites by 30.69%. The present study indicates that CpCaM is potentially involved in the growth of C. parvum. Results of the study expand our knowledge on the interaction between host and Cryptosporidium.

Past, current, and potential treatments for cryptosporidiosis in humans and farm animals: A comprehensive review.

The intracellular protozoan parasite of the genus Cryptosporidium is among the leading causes of waterborne diarrheal disease outbreaks throughout the world. The parasite is transmitted by ingestion of infective oocysts that are highly stable in the environment and resistant to almost all conventional disinfection methods and water treatments. Control of the parasite infection is exceedingly difficult due to the excretion of large numbers of oocysts in the feces of infected individuals that contaminate the environment and serve as a source of infection for susceptible hosts including humans and animals. Drug development against the parasite is challenging owing to its limited genetic tractability, absence of conventional drug targets, unique intracellular location within the host, and the paucity of robust cell culture platforms for continuous parasite propagation. Despite the high prevalence of the parasite, the only US Food and Drug Administration (FDA)-approved treatment of Cryptosporidium infections is nitazoxanide, which has shown moderate efficacy in immunocompetent patients. More importantly, no effective therapeutic drugs are available for treating severe, potentially life-threatening cryptosporidiosis in immunodeficient patients, young children, and neonatal livestock. Thus, safe, inexpensive, and efficacious drugs are urgently required to reduce the ever-increasing global cryptosporidiosis burden especially in low-resource countries. Several compounds have been tested for both in vitro and in vivo efficacy against the disease. However, to date, only a few experimental compounds have been subjected to clinical trials in natural hosts, and among those none have proven efficacious. This review provides an overview of the past and present anti-Cryptosporidium pharmacotherapy in humans and agricultural animals. Herein, we also highlight the progress made in the field over the last few years and discuss the different strategies employed for discovery and development of effective prospective treatments for cryptosporidiosis.

Wastewater treatment plants discharges disseminated more Giardia than Cryptosporidium.

Parasitic protozoa Giardia intestinalis and Cryptosporidium parvum are causative agents for giardiasis and cryptosporidiosis, respectively. These infections are mostly associated with waterborne diseases. The discharges from wastewater treatment plants (WWTPs) that reach surface waters cause waterborne transmission because there are no regulations for monitoring these protozoa. This emphasizes how crucial the removal capacities of WWTPs to prevent the spread of infectious parasitic pathogens. For this reason, in this study, five different types of WWTPs including conventional activated sludge (CAS), biological nutrient removal (BNR), sequencing batch reactor (SBR), membrane bioreactor (MBR), and WWTP with coagulation-flocculation and UV disinfection (CoFlUV) units were investigated over a year, seasonally in terms of their G. intestinalis and C. parvum removal capacities. The seasonal abundances of these protozoa-specific genes in both the influents and effluents of each WWTP were determined by qPCR. The reduction of protozoan rDNA copies in the effluent wastewater samples compared with the influent wastewater samples was assessed as log10 reduction values (LRVs). LRVs >3 were reachable for C. parvum in all types of WWTPs tested. However, only LRVs 1-2 were reachable for G. intestinalis in CAS, SBR, CoFlUV, and MBR. Significant seasonal variations were just observed in SBR and CAS for G. intestinalis and C. parvum (p < 0.05), respectively. The findings depicted that WWTPs tested disseminated more giardiasis causative agents than cryptosporidiosis. Therefore, G. intestinalis needs to be monitored in WWTPs' discharges to reduce any potential damage of this parasite to public health. PRACTITIONER POINTS: Removal of G. intestinalis and C. parvum in WWTPs was affected by the process. LRV 2.92 was the highest LRV achieved for G. intestinalis. LRV >3 was reachable for C. parvum. WWTPs discharges disseminated more G. intestinalis than C. parvum. WWTPs effluents should be monitored in terms of G. intestinalis.

Apical Secretory Glycoprotein Complex Contributes to Cell Attachment and Entry by Cryptosporidium parvum.

Cryptosporidium parvum is an enteric pathogen that invades epithelial cells in the intestine, where it resides at the apical surface in a unique epicellular location. Compared with those of related apicomplexan parasites, the processes of host cell attachment and invasion by C. parvum are poorly understood. The streamlined C. parvum genome contains numerous mucin-like glycoproteins, several of which have previously been shown to mediate cell attachment, although the majority are unstudied. Here, we identified the antigens recognized by monoclonal antibody (MAb) 1A5, which stains the apical end of sporozoites and mature merozoites. Immunoprecipitation with MAb 1A5 followed by mass spectrometry identified a heterodimer comprised of paralogous proteins which are related to additional orthologs in the genome of C. parvum and related species. Paralogous glycoproteins recognized by MAb 1A5 heterodimerize as a complex displayed on the parasite surface, and they also interact with lectins that suggest that they contain mucin-like, O-linked oligosaccharides. Although the gene encoding one of the paralogs was readily disrupted by CRISPR/Cas9 gene editing, its partner, which contains a mucin-like domain related to GP900, was refractory to deletion. Combined with the ability of MAb 1A5 to partially neutralize host cell attachment by sporozoites, these findings define a new family of secretory glycoproteins that participate in cell invasion by Cryptosporidium spp. IMPORTANCE Although Cryptosporidium is extremely efficient at penetrating mucus and invading epithelial cells in the intestine, the mechanism of cell attachment is poorly understood. To expand our understanding of this process, we characterized the antigens recognized by a monoclonal antibody that stains the apical end of invasive stages called sporozoites and merozoites. Our studies identify a family of glycoproteins that form heterodimers on the parasite cell surface to facilitate host cell attachment and entry. By further defining the role of mucin-like glycoproteins in host cell attachment, our studies may lead to strategies to disrupt cell adhesion and thereby decrease infection.

Molecular identification and antiprotozoal activity of silver nanoparticles on viability of Cryptosporidium parvum isolated from pigeons, pigeon fanciers and water.

Cryptosporidium is a protozoan that causes acute gastroenteritis, abdominal pain, and diarrhea in many vertebrate species, including humans, animals and birds. A number of studies have reported the occurrence of Cryptosporidium in domestic pigeons. Thus, this study aimed to identify Cryptosporidium spp. in samples collected from domestic pigeons, pigeon fanciers, and drinking water, as well as to investigate the antiprotozoal activity of biosynthesized silver nanoparticles (AgNPs) on the viability of isolated Cryptosporidium parvum (C. parvum). Samples were collected from domestic pigeons (n = 150), pigeon fanciers (n = 50), and drinking water (n = 50) and examined for the presence of Cryptosporidium spp. using microscopic and molecular techniques. The antiprotozoal activity of AgNPs was then assessed both in vitro and in vivo. Cryptosporidium spp. was identified in 16.4% of all examined samples, with C. parvum identified in 5.6%. The highest frequency of isolation was from domestic pigeon, rather than from pigeon fanciers or drinking water. In domestic pigeons, there was a significant association between Cryptosporidium spp. positivity and pigeon's age, droppings consistency, housing, hygienic and heath conditions. However, Cryptosporidium spp. positivity was only significantly associated with pigeon fanciers' gender and heath condition. The viability of C. parvum oocysts was reduced using AgNPs at various concentrations and storage times in a descending manner. In an in vitro study, the highest reduction in C. parvum count was observed at the AgNPs concentration of 1000 µg/mL after a 24 h contact time, followed by the AgNPs concentration of 500 µg/mL after a 24 h contact time. However, after a 48 h contact time, a complete reduction was observed at both 1000 and 500 µg/mL concentrations. Overall, the count and viability of C. parvum decreased with increasing the AgNPs concentration and contact times in both the in vitro and in vivo studies. Furthermore, the C. parvum oocyst destruction was time-dependent and increased with increasing the contact time at various AgNPs concentrations.

Role of Cryptosporidium spp in Development of Colorectal Cancer.

BACKGROUND: Colorectal cancer is one of the most common malignancies in humans. About 20% of the cancer incidence was attributed to infectious agents highlighting the association between infectious agents and the development of cancers. It has been suspected that Cryptosporidium spp. infection may be correlated with colon adenocarcinoma.  Aim: investigate the percentage of cryptosporidiosis among colorectal cancer patients. SUBJECTS: 100 patients were recruited from Medical Research Institute, Alexandria University. METHODS: Fresh stool specimens were collected, homogenized and examined using direct wet mount and by permanent staining of faecal smears using Modified ZN staining. Molecular detection by PCR amplification of Cryptosporidium COWP gene. RESULTS: Significantly higher proportion of colorectal cancer patients (32.5%, 42.5%) tested positive by MZN and ELISA respectively compared to only 3.3% and 5% of positive MZN and ELISA among control group. Also, positive PCR was detected among higher proportion of colorectal cancer patients (47.5%) and only 5% of control group. Odds of colorectal cancer is 19 times among positive cases of Cryptosporidium by PCR than those without proven infection by PCR (OR 19.12; 95% CI 4.82-75.99). Comparison of the assessment of Cryptosporidium infection made by two techniques produces a kappa value of 0.770, and .759 respectively between NZN, ELISA and PCR as a gold standard, suggesting a good agreement between the two techniques and PCR. This value of kappa is significantly different from zero, K.770, p<0.001 for MZN and K.759, p<.001 for ELISA. Specificity of MZN (100%) is higher than that of ELISA (96.2%) and both reported higher specificity than sensitivity denoting that both tests are good positive to rule in the presence of infection at 40% prevalence. CONCLUSION: Cryptosporidium infection is significantly higher among cancer colon patients reinforcing that it might be considered as a likely risk factor for the development cancer colon.

Occurrence and Molecular Characterization of Cryptosporidium Infection in HIV/Aids Patients in Algeria.

The estimated prevalence rate of adults living with HIV infection in MENA is one of the lowest in the world. To date, no data on the genetic characteristics of Cryptosporidium isolates from HIV/AIDS patients in Algeria were available. This study aimed to identify Cryptosporidium species and subtype families prevalent in Algerian HIV-infected patients and contribute to the molecular epidemiology mapping of Cryptosporidium in the MENA region. A total of 350 faecal specimens from HIV/AIDS patients were analysed using microscopy, and a Cryptosporidium infection was identified from 33 samples, with 22 isolates successfully sequencing and confirming species and subtypes. Based on sequence analysis, 15 isolates were identified as C. parvum with family subtypes IIa (n = 7) and IId (n = 8), while five were identified as C. hominis (family subtypes Ia (n = 2) and Ib (n = 3)) and two as C. felis. The C. parvum subtype families IIa and IId predominated, suggesting potential zoonotic transmission. More extensive sampling of both humans and farm animals, especially sheep, goats and calves, as well as a collection of epidemiological data are needed for a better understanding of the sources of human C. parvum infections in Algeria.

Molecular identification and genetic characteristics of Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi in human immunodeficiency virus/acquired immunodeficiency syndrome patients in Shanghai, China.

BACKGROUND: Opportunistic infections are a ubiquitous complication in human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) patients. Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi are common opportunistic intestinal pathogens in humans. In China, despite the number of HIV/AIDS patients being extremely large, only a few studies have investigated opportunistic infections caused by intestinal pathogens in this patient population. The aims of this study were to elucidate the occurrence and genetic characteristics of Cryptosporidium spp., G. duodenalis, and E. bieneusi in HIV/AIDS patients. METHODS: We collected fecal specimens from 155 HIV/AIDS patients (one from each patient). All of the specimens were examined for the presence of the pathogens by genotyping using polymerase chain reaction and sequencing of the small subunit ribosomal RNA gene for Cryptosporidium spp.; the triosephosphate isomerase, ß-giardin and glutamate dehydrogenase genes for G. duodenalis; and the internal transcribed spacer region of the rRNA gene for E. bieneusi. The Cryptosporidium-positive specimens were further subtyped by polymerase chain reacion and sequencing of the 60-kDa glycoprotein gene. RESULTS: Six (3.9%), three (1.9%), and eight (5.2%) HIV/AIDS patients were positive for Cryptosporidium spp., G. duodenalis, and E. bieneusi, respectively. No statistical differences were observed in occurrence rate between the groups by gender, clinical symptom (diarrhea), and CD4+ cell count. Four Cryptosporidium species were identified: Cryptosporidium hominis (n = 2), Cryptosporidium parvum (n = 1), Cryptosporidium meleagridis (n = 1), and Cryptosporidium andersoni (n = 2). Furthermore, two C. hominis subtypes (IeA12G3T3 and IaA28R4) were detected. Three G. duodenalis-positive specimens were successfully amplified and sequenced at the triosephosphate isomerase and ß-giardin loci, which led to the identification of assemblages C and B, respectively. Seven genotypes (D, Type IV, EbpC, Peru11, EbpD, A, and I) were identified in E. bieneusi-positive specimens. CONCLUSIONS: Our findings should increase awareness of AIDS-related opportunistic intestinal pathogens, and indicate the need for routine examination in clinical practice for the detection of Cryptosporidium spp., G. duodenalis, and E. bieneusi. Homology analyses of the three intestinal pathogens at the nucleotide and/or amino acid levels indicated their zoonotic potential.