Enteric parasites Cyclospora cayetanensis and Cryptosporidium hominis in domestic and wildlife animals in Ghana

BACKGROUND

Enteric parasitic infections remain a major public health problem globally. Cryptosporidium spp., Cyclospora spp. and Giardia spp. are parasites that cause diarrhea in the general populations of both developed and developing countries. Information from molecular genetic studies on the speciation of these parasites and on the role of animals as vectors in disease transmission is lacking in Ghana. This study therefore investigated these diarrhea-causing parasites in humans, domestic rats and wildlife animals in Ghana using molecular tools.

METHODS

Fecal samples were collected from asymptomatic school children aged 9-12 years living around the Shai Hills Resource Reserve (tourist site), from wildlife (zebras, kobs, baboons, ostriches, bush rats and bush bucks) at the same site, from warthogs at the Mole National Park (tourist site) and from rats at the Madina Market (a popular vegetable market in Accra, Ghana. The 18S rRNA gene (18S rRNA) and 60-kDa glycoprotein gene (gp60) for Cryptosporidium spp., the glutamate dehydrogenase gene (gdh) for Giardia spp. and the 18S rDNA for Cyclospora spp. were analyzed in all samples by PCR and Sanger sequencing as markers of speciation and genetic diversity.

RESULTS

The parasite species identified in the fecal samples collected from humans and animals included the Cryptosporidium species C. hominis, C. muris, C. parvum, C. tyzzeri, C. meleagridis and C. andersoni; the Cyclopora species C. cayetanensis; and the Gardia species, G. lamblia and G. muris. For Cryptosporidium, the presence of the gp60 gene confirmed the finding of C. parvum (41%, 35/85 samples) and C. hominis (29%, 27/85 samples) in animal samples. Cyclospora cayetanensis was found in animal samples for the first time in Ghana. Only one human sample (5%, 1/20) but the majority of animal samples (58%, 51/88) had all three parasite species in the samples tested.

CONCLUSIONS

Based on these results of fecal sample testing for parasites, we conclude that animals and human share species of the three genera (Cryptosporidium, Cyclospora, Giardia), with the parasitic species mostly found in animals also found in human samples, and vice-versa. The presence of enteric parasites as mixed infections in asymptomatic humans and animal species indicates that they are reservoirs of infections. This is the first study to report the presence of C. cayetanensis and C. hominis in animals from Ghana. Our findings highlight the need for a detailed description of these parasites using high-throughput genetic tools to further understand these parasites and the neglected tropical diseases they cause in Ghana where such information is scanty.

Single-strand conformation polymorphism-based genetic characterization of the Cyclospora cayetanensis strains collected from different provinces in Turkey

INTRODUCTION AND OBJECTIVE

Cyclospora cayetanensis, a coccidian protozoan species, has been recently found to cause diarrhea in all age groups in immunocompetent and immunocompromised individuals in most regions of the world. This study aimed to conduct the molecular detection of C. cayetanensis and to determine the genetic diversity of the 18S ribosomal RNA (rRNA) gene sequence of C. cayetanensis isolated from individuals living in different provinces in Turkey by using PCR-single-strand conformation polymorphism (SSCP).

MATERIAL AND METHODS

A total of 22 subjects were included in the study. Fourteen of the subjects were female and eight were male, with ages ranging between 7-65 years. Stool specimens were examined using wet mount and modified acid-fast staining methods, which revealed the presence of oocysts in the samples. The 18S rRNA ITS-1 Ccits37f-GCTTGCTATGTTTTAGCATGTGG and Ccits501r-GCACAATGAATGCACACACA gene regions were used as primers. The PCR products were analyzed by agarose gel electrophoresis and visualized on a UV transilluminator. For the SSCP, the PCR products were denatured with formamide, run for 16 h in 6% (49:1) polyacrylamide gel, and then imaged with silver staining.

RESULTS

SSCP assay was performed given that the DNA strands demonstrated different folds; the DNA strands contain different nucleotides based on the PCR-SSCP results for the Cyclospora strains collected in 4 provinces. Moreover, 3 different band profiles were observed in the investigated samples. A slight mutation difference was observed among the strains collected.

CONCLUSIONS

Further comprehensive studies involving more C. cayetanensis-positive specimens and utilizing different mutation screening methods are warranted to demonstrate mutation differences in Cyclopora strains in Turkey.

Molecular typing of Cyclospora cayetanensis in produce and clinical samples using targeted enrichment of complete mitochondrial genomes and next-generation sequencing

BACKGROUND

Outbreaks of cyclosporiasis, a diarrheal illness caused by Cyclospora cayetanensis, have been a public health issue in the USA since the mid 1990's. In 2018, 2299 domestically acquired cases of cyclosporiasis were reported in the USA as a result of multiple large outbreaks linked to different fresh produce commodities. Outbreak investigations are hindered by the absence of standardized molecular epidemiological tools for C. cayetanensis. For other apicomplexan coccidian parasites, multicopy organellar DNA such as mitochondrial genomes have been used for detection and molecular typing.

METHODS

We developed a workflow to obtain complete mitochondrial genome sequences from cilantro samples and clinical samples for typing of C. cayetanensis isolates. The 6.3 kb long C. cayetanensis mitochondrial genome was amplified by PCR in four overlapping amplicons from genomic DNA extracted from cilantro, seeded with oocysts, and from stool samples positive for C. cayetanensis by diagnostic methods. DNA sequence libraries of pooled amplicons were prepared and sequenced via next-generation sequencing (NGS). Sequence reads were assembled using a custom bioinformatics pipeline.

RESULTS

This approach allowed us to sequence complete mitochondrial genomes from the samples studied. Sequence alterations, such as single nucleotide polymorphism (SNP) profiles and insertion and deletions (InDels), in mitochondrial genomes of 24 stool samples from patients with cyclosporiasis diagnosed in 2014, exhibited discriminatory power. The cluster dendrogram that was created based on distance matrices of the complete mitochondrial genome sequences, indicated distinct strain-level diversity among the 2014 C. cayetanensis outbreak isolates analyzed in this study.

CONCLUSIONS

Our results suggest that genomic analyses of mitochondrial genome sequences may help to link outbreak cases to the source.

Mitochondrial Junction Region as Genotyping Marker for Cyclospora cayetanensis

Cyclosporiasis is an infection caused by Cyclospora cayetanensis, which is acquired by consumption of contaminated fresh food or water. In the United States, cases of cyclosporiasis are often associated with foodborne outbreaks linked to imported fresh produce or travel to disease-endemic countries. Epidemiologic investigation has been the primary method for linking outbreak cases. A molecular typing marker that can identify genetically related samples would be helpful in tracking outbreaks. We evaluated the mitochondrial junction region as a potential genotyping marker. We tested stool samples from 134 laboratory-confirmed cases in the United States by using PCR and Sanger sequencing. All but 2 samples were successfully typed and divided into 14 sequence types. Typing results were identical among samples within each epidemiologically defined case cluster for 7 of 10 clusters. These findings suggest that this marker can distinguish between distinct case clusters and might be helpful during cyclosporiasis outbreak investigations.

Molecular detection and genotyping of pathogenic protozoan parasites in raw and treated water samples from southwest Colombia

BACKGROUND

Protozoan parasites such as Giardia duodenalis, Cryptosporidium spp., Cyclospora cayetanensis, Toxoplasma gondii and Entamoeba histolytica represent a great challenge to the systems producing water for human consumption because their cystic forms are persistent in the environment and resist to the disinfection methods conventionally used for their control. In this study, we investigated the presence of these protozoan pathogens in both raw and treated water samples used for the production of drinking water in Nariño Department, southwest Colombia. We collected 110 water samples (10 lof each sample) and analyzed them with real-time PCR (qPCR). qPCR-positive samples were genotyped with PCR and DNA sequencing.

RESULTS

Giardia duodenalis was detected in 35/110 (31.8%) of the samples and Cryptosporidium spp. in 9/110 (8.2%) of the samples; no sample was positive for T. gondii, E. histolytica or C. cayetanensis. Giardia duodenalis was detected in samples of both raw water (Drinking Water Treatment Plants (DWTP): 47.83%;Drinking Water Rural Plants (DWRP): 18.42%) and water collected either after conventional physicochemical treatment (26.09%) or after disinfection by chlorine (50%), whereas Cryptosporidium spp. were only detected in raw waters (DWTP: 17.39%; DWRP: 13.16%). The two pathogens were detected in both types of treatment plants supplying water to urban areas and to rural zones. Analysis of gdh and tpi markers identified assemblages AI, AII and H of G. duodenalis, while analysis of the small subunit rRNA and gp60 markers of Cryptosporidium-positive samples identified C. parvum (Subtype IIcA5G3c), C. galli, C. molnari, Cryptosporidium sp. genotype II of bats and Cryptosporidium sp. genotype VIII of birds.

CONCLUSIONS

The results obtained demonstrate the presence of protozoan parasites in the water of the study region, and the need to improve the surveillance systems for these pathogens and identify the corresponding sources of contamination.

Pathogenic characteristics of a novel intranuclear coccidia in Japanese black calves and its genetic identification as Eimeria subspherica

Bovine intranuclear coccidiosis is caused by the protozoans Eimeria alabamensis and Cyclospora spp. Here, we characterized the disease and genetically identified the causative species in Japanese black calves with chronic and refractory watery diarrhea. Histologic examinations revealed atrophy of the jejunal villi and numerous parasites in the nucleus of epithelial cells in the jejunum. Based on molecular analyses using 18S ribosomal RNA gene-specific primers that we designed, the parasites were found to be formed in the same cluster as Eimeria subspherica in the phylogenetic tree, which was separated from those of other related Eimeria spp. These results constitute the first report of E. subspherica as a cause of bovine intranuclear coccidiosis.

Molecular detection of Cyclospora in water, soil, vegetables and humans in southern Italy signals a need for improved monitoring by health authorities

To date, in Europe, there is scant information on the occurrence of Cyclospora in water from treatment plants and in humans, and no data are available on soil or fresh plant products. Here, we undertook the first molecular survey of Cyclospora in multiple biological matrices collected from the Apulia region of southern Italy. Samples of irrigation water from four municipal treatment plants, eight different types of vegetables or fruit (cucumber, lettuce, fennel, celery, tomato, melon, endive and chicory) and soil from the same farms on which these plants were grown, as well as faecal samples from humans living in the same region were tested by qPCR-coupled single-strand conformation polymorphism (SSCP) analysis and DNA sequencing. Cyclospora was detected in 15.5% of all 213 samples tested. Specifically, this protist was detected in (i) treated water (21.3% of 94 samples), well water (6.2% of 16), but not drinking water (0% of 3); (ii) soil (11.8% of 51 samples) and vegetables (12.2% of 49), with the highest prevalence (18.7%) on fennel; and (iii) human stools (27.5% of 40 samples). In environmental and food samples, Cyclospora was detected mainly in autumn and was significantly more prevalent in the faeces from humans of 40-50 years of age. This is the first comprehensive molecular survey of Cyclospora in environmental, food and human faecal samples in Europe. These data suggest that irrigation water, soil and vegetables might be contaminated by Cyclospora cayetanensis, which might represent a source of infection to humans in the study area and calls for monitoring by health authorities.

Molecular characterization of Cyclospora-like organisms from golden snub-nosed monkeys in Qinling Mountain in Shaanxi province, northwestern China

Cyclospora spp. have been identified as one of the most important intestinal pathogens causing protracted diarrhea in animals and human beings. To determine the Cyclospora species in the non-human primate Rhinopithecus roxellanae, a total of 71 fecal samples from 19 endangered snub-nosed monkeys in Shaanxi province were collected and examined using Sheater's sugar flotation technique and by sequencing the fragments of 18S rDNA. Only two Cyclospora isolates from 2 golden snub-nosed monkeys (R. roxellanae) were obtained and identified between July 2011 and August of 2012. The sequences of the 18S rDNA for the two Cyclospora isolates were 477 bp, with no nucleotide variation between them. Phylogenetic analysis based on the 18S rDNA sequences revealed that the two Cyclospora isolates were posited into the clade Cyclospora spp. and sistered to C. colobi. These results first showed that Cyclospora infection occurred in R. roxellanae in hot and rainy weather, which would provide useful information for further understanding the molecular epidemiology of Cyclospora spp. and the control of Cyclospora infection in non-human primates as well as in human beings.

Molecular characterization of human-pathogenic microsporidia and Cyclospora cayetanensis isolated from various water sources in Spain: a year-long longitudinal study

Recent studies suggest the involvement of water in the epidemiology of Cyclospora cayetanensis and some microsporidia. A total of 223 samples from four drinking water treatment plants (DWTPs), seven wastewater treatment plants (WWTPs), and six locations of influence (LI) on four river basins from Madrid, Spain, were analyzed from spring 2008 to winter 2009. Microsporidia were detected in 49% of samples (109/223), Cyclospora spp. were detected in 9% (20/223), and both parasites were found in 5.4% (12/223) of samples. Human-pathogenic microsporidia were detected, including Enterocytozoon bieneusi (C, D, and D-like genotypes), Encephalitozoon intestinalis, Encephalitozoon cuniculi (genotypes I and III), and Anncaliia algerae. C. cayetanensis was identified in 17 of 20 samples. To our knowledge, this is the first study that shows a year-long longitudinal study of C. cayetanensis in drinking water treatment plants. Additionally, data about the presence and molecular characterization of the human-pathogenic microsporidia in drinking water, wastewater, and locations of influence during 1 year in Spain are shown. It is noteworthy that although the DWTPs and WWTPs studied meet European and national regulations on water sanitary quality, both parasites were found in water samples from these plants, supporting the idea that new and appropriate controls and regulations for drinking water, wastewater, and recreational waters should be proposed to avoid health risks from these pathogens.

Molecular surveillance of Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi by genotyping and subtyping parasites in wastewater

Background

Despite their wide occurrence, cryptosporidiosis and giardiasis are considered neglected diseases by the World Health Organization. The epidemiology of these diseases and microsporidiosis in humans in developing countries is poorly understood. The high concentration of pathogens in raw sewage makes the characterization of the transmission of these pathogens simple through the genotype and subtype analysis of a small number of samples.

Methodology/Principal Findings

The distribution of genotypes and subtypes of Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi in 386 samples of combined sewer systems from Shanghai, Nanjing and Wuhan and the sewer system in Qingdao in China was determined using PCR-sequencing tools. Eimeria spp. were also genotyped to assess the contribution of domestic animals to Cryptosporidium spp., G. duodenalis, and E. bieneusi in wastewater. The high occurrence of Cryptosporidium spp. (56.2%), G. duodenalis (82.6%), E. bieneusi (87.6%), and Eimeria/Cyclospora (80.3%) made the source attribution possible. As expected, several human-pathogenic species/genotypes, including Cryptosporidium hominis, Cryptosporidium meleagridis, G. duodenalis sub-assemblage A-II, and E. bieneusi genotype D, were the dominant parasites in wastewater. In addition to humans, the common presence of Cryptosporidium spp. and Eimeria spp. from rodents indicated that rodents might have contributed to the occurrence of E. bieneusi genotype D in samples. Likewise, the finding of Eimeria spp. and Cryptosporidium baileyi from birds indicated that C. meleagridis might be of both human and bird origins.

Conclusions/Significance

The distribution of Cryptosporidium species, G. duodenalis genotypes and subtypes, and E. bieneusi genotypes in urban wastewater indicates that anthroponotic transmission appeared to be important in epidemiology of cryptosporidiosis, giardiasis, and microsporidiosis in the study areas. The finding of different distributions of subtypes between Shanghai and Wuhan was indicative of possible differences in the source of C. hominis among different areas in China.

[Cyclospora cayetanensis and Cryptosporidium parvum coinfection in a pregnant woman with prolonged diarrhoea]

Cyclospora cayetanensis which is a recently described pathogen, is associated with prolonged diarrheae and history of travelling to tropical regions and intake of suspicious food and water. Cryptosporidium parvum is another pathogen that causes severe diarrhea defined initially in especially AIDS patients since 1980's. Cases of cyclosporiasis are frequently missed, since it is difficult to detect the parasite in human fecal samples, despite an increasing amount of data regarding this parasite. To identify both of these coccidian protozoa, faeces should be examined by modified acid-fast stain. Co-incidence of C. cayetanensis and C. parvum is seen rarely in Turkey. In this case report, C. cayetanensis and C. parvum found in a 28 years old pregnant women living in continental climate and without a history of travel, were presented. The patient had prolonged diarrhea and investigation of the feces by modified acid-fast and carbol fuchsin stains revealed C. cayetanensis and C. parvum. The immunoglobulin and lymphocyte subgroup testing done for the evaluation of the immune status of the patient, were all within normal limits. Following treatment with trimethoprim-sulfamethoxazole for 15 days, the oocyst number in feces has decreased. However, hepatic vein thrombosis and liver failure have developed in the postnatal period and she was diagnosed as Budd-Chiari syndrome. It was concluded that when the effect of pregnancy on immunity was taken into account, C. cayetonensis and C. parvum should be considered in cases of prolonged diarrhoeae in pregnant women.

Combined PCR-oligonucleotide ligation assay for detection of dairy cattle-derived Cyclospora sp

A rapid and sensitive assay for the detection of Cyclospora species in dairy cattle faecal specimens has been developed. The method utilizes a nested PCR to amplify a 168-bp DNA fragment of the 18S rRNA gene of cattle-derived Cyclospora sp. and an enzyme-linked immunosorbent assay (ELISA)-based oligonucleotide ligation assay (OLA) to detect the amplified product. In this study, the OLA technique was compared with conventional gel electrophoresis for the detection of amplified product. In evaluating the PCR-OLA for Cyclospora sp. and non-Cyclospora parasites, A(405) reading value for Cyclospora species was significantly higher than those for non-Cyclospora control. At known concentrations of purified amplicons from cattle-derived Cyclospora sp., the OLA was able to detect more than 0.5 ng of the amplified DNA. Of 168 clinical specimens collected from four dairy cattle farms, 6 were positive by both PCR-gel electrophoresis and the PCR-OLA procedure, and 2 were positive only by PCR-OLA, indicating the PCR-OLA procedure was more sensitive than the common way with gel electrophoresis. The results indicated that the PCR-OLA is simple, rapid and suitable in clinical detection of cattle-derived Cyclospora species.

Molecular characterization of Cyclospora-like organism from dairy cattle

Cyclospora cayetanensis was identified as the cause of large outbreaks of diarrhea in many parts of the world, but its host range and reservoirs remains poorly defined. Recently, oocysts resembling the C. cayetanensis were detected in dairy cattle fecal specimens from China. The 18S rDNA from two of these Cyclospora-like oocyst specimens from dairy cattle was amplified and sequenced. Phylogenetic analysis indicated that these cattle-associated Cyclospora-like organisms are nearly identical to each other and belong to the group of primate-derived Cyclospora, which are the closest known relatives of C. cayetanensis; while these cyclosporans constitute a coherent clade within the diverse group of Eimeria species. Moreover, on the basis of our finding that ruminant- and avian-associated Eimeria species are different in MnlI sites, a new PCR-restriction fragment length polymorphism protocol with primers NesCycF and NesCycR was developed to distinguish the Cyclospora species from ruminant-associated Eimeria species.

The genus Cyclospora (Apicomplexa: Eimeriidae), with a description of Cyclospora schneideri n.sp. in the snake Anilius scytale scytale (Aniliidae) from Amazonian Brazil--a review

A review is made of the recorded species of the coccidian genus Cyclospora and major events leading up to the discovery of C. cayetanensis, which is responsible for serious outbreaks of diarrhoea in man and is one of the aetiological agents of "traveller's diarrhoea". Humans appear to be the specific hosts, with the entire life-cycle in the intestine: to date there is no convincing evidence that the disease is a zoonosis. A description is given of oocysts and endogenous stages of C. schneideri n.sp., in the snake Anilius scytale scytale. Sporulation is exogenous and completed after about one week at 24-26 degrees. Mature oocysts 19.8 x 16.6 (15.1 x 13.8-25.7 x 20.1), shape-index 1.2 (1.0-1.3): no oocyst residuum or polar bodies. Oocyst wall a single colourless, smooth layer with no micropyle: it is rapidly deformed or broken. Sporocysts 13.6 x 9.4 (11.3 x 8.3-15.1 x 9.9), shape-index 1.4 (1.2-1.5) with an inconspicuous Stieda body. Sporozoites 11-13 x 2.5-3. Endogenous stages are intracytoplasmic in the epithelial cells of the small intestine and with the characters of the Eimeriorina.

Cyclospora cayetanensis, a food- and waterborne coccidian parasite

Food- and waterborne coccidia including Cryptosporidium parvum, Cyclospora cayetanensis, Sarcocystis hominis and Sarcocystis suihominis, and Isospora belli are cyst-forming apicomplexan protozoa that cause intracellular infections, predominantly in the epithelial cells of the intestine. They are transmitted by oocysts from person-to-person by the fecal-oral route or via contaminated water or food. The most common symptom of infection is diarrhea, however, asymptomatic infections occur. Infections are associated with intestinal inflammation, with pathological lesions such as villus blunting, and abnormal function such as malabsorption. Mild-to-moderate, self-limiting diarrhea is common in healthy individuals ingesting infective stages of these organisms. However, patients with immune dysfunction can have severe intestinal injury and prolonged diarrhea. Diagnosis in many cases is made by a microscopic examination of the stool, and the use of appropriate staining techniques, but more recently molecular methods for detection are used increasingly. Effective antimicrobial treatment for prolonged infection in immunocompromised patients is available for most of these infections. These gastrointestinal coccidial pathogens have important similarities in epidemiology, disease pathogenesis, clinical manifestations, diagnosis, and treatment. Although there are many other cyst-forming coccidia of public health, veterinary and/or economic importance, discussion in this chapter will be limited to C. cayetanensis, as an important example of the group. Aspects of the biology, epidemiology, diagnosis, disease, treatment and control are considered. This parasite is considered to be an emerging pathogen. From 1990 to 2000, there were 11 foodborne outbreaks of cyclosporosis in North America that affected at least 3600 people. There are many outstanding questions regarding this parasite and under-reporting is common because general diagnostic methods for intestinal parasites are inadequate for detection of Cyclospora.

Sensitivity of PCR detection of Cyclospora cayetanensis in raspberries, basil, and mesclun lettuce

The sensitivity of a polymerase chain reaction (PCR) method for detection of Cyclospora cayetanensis in raspberries, basil, and mesclun lettuce was evaluated. The assay could detect 40 or fewer oocysts per 100 g of raspberries or basil, but had a detection limit of around 1000 per 100 g in mesclun lettuce.

Cyclospora cayetanensis: a review of an emerging parasitic coccidian

Cyclospora cayetanensis is a sporulating parasitic protozoan that infects the upper small intestinal tract. It has been identified as both a food and waterborne pathogen endemic in many developing countries. It is an important agent of Traveller's Diarrohea in developed countries and was responsible for numerous foodborne outbreaks in the United States and Canada in the late 1990s. Like Cryptosporidium, infection has been associated with a variety of sequelae such as Guillain-Barré syndrome, reactive arthritis syndrome (formally Reiter syndrome) and acalculous cholecystitis. There has been much debate as to where to place C. cayetanensis taxonomically due to its homology with Eimeria species. To date, the only genomic DNA sequences available are the ribosomal DNA of C. cayetanensis and three other species; within these a high degree of homology has been observed. This homology and the lack of sequence data from other Cyclospora species have hindered identification methods.

[Identification of species of Cyclospora isolates from patients by the PCR-based diagnostic methods]

Cyclospora cayetanensis is an intestinal coccidian parasite and known as a human pathogen causing watery diarrhea. Recently, Cyclospora organisms, morphologically indistinguishable from C. cayetanensis, were detected from the several species of primates, and three new species named, C. cercopitheci, C. colobi, and C. papionis, have been proposed to the isolates on the basis of the genetic differences. The infectivity of these species to humans is strictly unknown, and there is a possibility of infection with not only C. cayetanensis but also the species from primates among patients. Therefore, it is necessary for the accurate diagnosis of Cyclospora infection to distinguish among the Cyclospora species. In the present study, we identified species of Cyclospora isolates from patients by the PCR-based diagnostic method. Since the sequence of Cyclospora 18S ribosomal RNA gene generated with the primary pair CYC1 FE and CYC4RB is found to be variable among Cyclospora species, we applied the PCR-direct sequencing using above primers to identify species of the isolates. Consequently, the diagnostic fragment was amplified by the PCR in all isolates, and the sequence of the PCR product obtained from each isolate was completely identical to that of C. cayetanensis. Therefore, we identified the isolates from patients as C. cayetanensis. On the basis of the results obtained in the present study, it is supposed that the PCR-direct sequencing using the primer pair CYC1FE and CYC4RB is a useful tool for the distinction among Cyclospora species.

A survey for Cyclospora spp. in Kenyan primates, with some notes on its biology

From March 1999 through August 2000, 511 stool samples collected from 11 different primate species in 10 geographically distinct locations in Kenya, East Africa, were screened for the presence of Cyclospora spp. oocysts. Positive samples (43/102, 42%) were identified in vervet monkeys (Cercopithecus aethiops) in 4 of 4 locations; 19/206 (9%) in yellow and olive baboons (Papio cynocephalus, P. anubis, respectively) in 5 of 5 locations; and 19/76 (25%) in black and white colobus monkeys (Colobus angolensis, C. guereza, respectively) from 2 of 3 locations. DNA sequences obtained from 18 S rRNA coding regions from respective subsets of these positive samples were typed as Cyclospora cercopitheci (samples from Cercopithecus aethiops). Cyclospora papionis (samples from Papio cynocephalus and P. anubis), and Cyclospora colobi (samples from Colobus angolensis and C. guereza). Cyclospora oocysts were not detected in samples collected from patas, highland sykes, lowland sykes, blue sykes, DeBrazza, or red-tailed monkeys. A coded map showing the geographic location of the collected samples is given. Stool samples from 1 troop of vervet monkeys were collected over a 12-mo period. Positive samples ranged between 21 and 63%. These results suggest that there is no strongly marked seasonality evident in Cyclospora infection in monkeys as has been noted in human infection. This is further confirmed by the recovery of positive samples collected from vervet monkeys, baboons, and colobus monkeys at all times of the year during this survey. This absence of seasonality in infection is especially notable because of the extreme weather patterns typical of Kenya, where marked rainy and dry seasons occur. A second noteworthy observation is that the striking host specificity of the Cyclospora species initially described was confirmed in this survey. Baboons were only infected with C. papionis, vervet monkeys with C. cercopitheci, and colobus monkeys with C. colobi, despite geographic overlaps of both the monkey and parasite species and wide geographic distribution of each parasite and monkey host.

Sequence variability in the first internal transcribed spacer region within and among Cyclospora species is consistent with polyparasitism

Cyclospora cayetanensis is a coccidian parasite which causes severe gastroenteritis in humans. Molecular information on this newly emerging pathogen is scarce. Our objectives were to assess genetic variation within and between human-associated C. cayetanensis and baboon-associated Cyclospora papionis by examining the internal transcribed spacer (ITS) region of the ribosomal RNA operon, and to develop an efficient polymerase chain reaction- (PCR)-based method to distinguish C. cayetanensis from other closely related organisms. For these purposes, we studied C. cayetanensis ITS-1 nucleotide variability in 24 human faecal samples from five geographic locations and C. papionis ITS-1 variability in four baboon faecal samples from Tanzania. In addition, a continuous sequence encompassing ITS-1, 5.8S rDNA and ITS-2 was determined from two C. cayetanensis samples. The results indicate that C. cayetanensis and C. papionis have distinct ITS-1 sequences, but identical 5.8S rDNA sequences. ITS-1 is highly variable within and between samples, but variability does not correlate with geographic origin of the samples. Despite this variability, conserved species-specific ITS-1 sequences were identified and a single-round, C. cayetanensis-specific PCR-based assay with a sensitivity of one to ten oocysts was developed. This consistent and remarkable diversity among Cyclospora spp. ITS-1 sequences argues for polyparasitism and simultaneous transmission of multiple strains.

Experimental studies on cyclosporiosis

Swiss albino mice get Cyclospora infection after orally inoculated with sporulated oocysts. Two weeks post inoculation, most of them passed numerous acid fast immature oocysts in their stools. One week later, light microscopic examination of their intestinal H & E stained sections revealed parasitic stages in a supranuclear location within enterocytes. They were most prominent in the mucosal villi. Lamina propria was expanded by an inflammatory infiltrate. The combined parasitological and histopathological present studies helped in distinguishing Cyclospora which is often confused with Cryptosporidia in stool samples and with Isospora in intestinal sections. Electron microscopy demonstrated both sexual and asexual developmental stages of Cyclospora in ultrathin infected sections. Therefore, Cyclospora species require only a single host to complete its entire life cycle

[Usefulness of the molecular techniques for detecting and/or identifing of parasites and fungi in humans and animals or pathogens transmitted by ticks (Part I)]

After a long period of using basic microscopic, immunological and biochemical methods for diagnosis, rapid development of nucleic acids investigation enabled introduction of specific and sensitive methods of detection of pathogenic agents on the molecular level. Among others, polymerase chain reaction (PCR), discovered in mid of 80'ies and then automatized, offered an attractive alternative to conventional testing systems. In this paper we describe reliable diagnostic tests widely used in the world, including Poland, and capable of detecting different disease agents as parasites and fungi in clinical specimens and pathogens of emerging zoonotic diseases in ticks. The possibilities of using molecular methods for determination of Plasmodium falciparum drug resistance is also discussed. Moreover, the report offers information concerning kinds of molecular tests and institutions in which there are executed.

Cyclospora cayetanensis--an emerging coccidian parasite

Over the last decade increasing number of enteritis cases have been attributed to infection with a new coccidian sp that was named Cyclospora cayetanensis in 1993. Diarrhoea caused by this agent is clinically indistinguishable from cryptosporidiasis, isosporiasis and microsporidiasis but cyclospora infection are often very prolonged (upto 15 weeks) and may cause severe weight loss. Diagnosis is important because unlike diarrhoea caused by cryptosporidium and microsporidium, treatment with co-trimoxazole is effective. We report here a case of cyclosporiasis, to increase awareness of possibility of cyclospora infection in patients with prolonged diarrhoea. It should be considered in assessment of patients with unexplained prolonged diarrhoeal illness.