Detection Of Cryptosporidium Parvum Research Articles

Detection of Cryptosporidium parvum in locally manufactured yoghurt and Kareish cheese

Detection of Cryptosporidium parvum in locally manufactured yoghurt and Kareish cheese

Detection of Cryptosporidium parvum by modified acid-fast stain among cancer patients in Thi-Qar province

Cryptosporidium parvum is a widespread opportunistic parasite belonging to the family Apicomplexa that completes its life cycle in a single host and is found frequently in immunocompromised persons, especially in patients with cancer. This research's objectives were to determine the prevalence of Cryptosporidium parvum infection among cancer patients in the Thi-Qar Province of Iraq, using modified Ziehl-Neelsen (MZN) stain. This study included 300 stool samples, 200 of which were for patients with cancer and 100 were for healthy people (the control group). Based on the modified acid-fast stain, the results showed the rate of infection with Cryptosporidium parvum among cancer patients was 54.0% (108/200) compared to 30.0% (30/100) in the control group, and there were statistically significant differences between them .And the percentage of infection among cancer patients in males was higher than in females, but there were no significant differences between them, as the percentage was 57.14% and 52.03%, respectively. As for the age groups Cryptosporidium parvum it affects all age groups in different proportions. The study showed that the highest infection rate among the age groups reached ?60 years at a rate of 64.44%, and the lowest infection rate among the age group ?20 years at a rate of 35.71%. As for the number doses of chemotherapy the results showed that the infection rate was higher in patients who received half and more than half of the doses of chemotherapy, where the percentage of those who received 16-20 doses (64.0%)

Detection of cryptosporidium parvum in cat by conventional methods and nested PCR in Al-Diwaniyah province

This study was conducted in Al-Diwaniyah province / Iraq during the period from September 2021 to the end of February 2022 to determine the Infection rate of Cryptosporidium spp parasites in cat to study the effect of some epidemiological factors such as age , gender, months and type of cat, as well as molecular determination of Cryptosporidium spp. by amplification of 18srRNA gene by N-PCR. fecal samples were collected from 100 domestic cats and stained by Ziehl-Neelsen stain. Microscopic examination results showed that 33% of 100 stool samples were infected by Cryptosporidium spp. the highest percentage was in September and October at 40% , and the infection rates was 40% in males compared to females at 30% and in young 42% while in adults 24%, and for domestic and stray cats about 40% compared with pet shop 22.5% where there was no significant difference at P<0.05. Genomic DNA was extracted From 100 fecal samples, the 18srRNA gene for C. parvum was amplified by N-PCR . The (N-PCR) technique showed that out of 100 stools 35% of the samples were positive for C.parvum.

Detection of Cryptosporidium Parvum Oocysts in Artificially Contaminated Filter Backwash Water and Ozone Treatment at Pilot Scale

ABSTRACT Waterborne diseases are a relevant concern for public health systems since commonly applied treatment techniques may not remove all water contaminants. Cryptosporidium spp. oocysts are an issue in water treatment plants due to their reduced size and resistance to the disinfection process (e.g., chlorination). Moreover, oocysts retained on the filter media might recirculate amongst the filter backwash water (FBW). This study aimed to detect Cryptosporidium parvum oocysts artificially inoculated on the FBW and evaluate the ozone treatment performance. A synthetic FBW underwent three concentration methods followed by immunomagnetic separation: calcium carbonate flocculation, direct centrifugation, and direct centrifugation with the 7X ICN dispersion solution. The latter method was selected as it presented less interference on oocyst viability (37.2% reduction) and higher recovery (22.1%) on preliminary assays. The recovery for the commercial suspensions was 15.4 ± 3.3%, although the analytical quality performed with EasySeed® suspension obtained a recovery of 2.8 ± 0.8%. These limitations and methodologies for protozoan detection are challenging due to low recoveries, especially in complex matrices. Finally, FBW ozonation was performed on a pilot scale, and the propidium iodide dye indicated oocyst viability decreased after treatment. Oocyst inactivation was 2.83 log and 3.44 log for dosages of 7.5 mg O3 L−1 for 10 min (i.e., 75 mg min L−1) and 10 mg O3 L−1 for 5 min (i.e., 50 mg min L−1), respectively. Disinfection is a crucial pathway for addressing outbreak scenarios, and ozone treatment should be further studied.

Cryptosporidiosis outbreak on a dairy farm: Detection of Cryptosporidium parvum as a causative agent in the water source.

Diarrhea caused by parasitic agents is common in neonatal calves and leads to significant economic losses in cattle farms worldwide. Cryptosporidium spp. is one of the most frequently detected parasitic agents causing diarrhea in neonatal calves. The aim of this study was to investigate the presence of Cryptosporidium spp. on a dairy farm which a has major diarrhea problem. Samples were collected from calves, cows, drinking bowls, and two different artesian water sources, as well as from the environment. All fecal samples were investigated using Kinyoun acid-fast stained slides and real-time PCR targeting the Cryptosporidium spp. COWP gene. In addition, species identification was performed by nested PCR targeting the Cryptosporidium spp. COWP gene and sequencing. Cryptosporidium spp. was detected in 11 calves (30.55%; 11/36) by real-time PCR and the cows were negative. Among real-time PCR positive samples, only five were also found positive by microscopy. Moreover, Cryptosporidium spp. was found in one of the two artesian water sources and five environmental samples by real-time PCR. Among these positive samples, eight were sequenced. According to the RFLP pattern, BLAST and, phylogenetic analyses, all sequenced samples were Cryptosporidium parvum. These findings show the importance of C. parvum as a cause of calf diarrhea on dairy farms.

Highly sensitive magnetic-microparticle-based aptasensor for Cryptosporidium parvum oocyst detection in river water and wastewater: Effect of truncation on aptamer affinity

Many methods have been reported to detect Cryptosporidium parvum (C. parvum) oocysts in the water environment using monoclonal antibodies. Herein, we report the use of DNA aptamers as an alternative ligand. We present the highly sensitive detection of C. parvum oocysts in wastewater samples based on aptamer-conjugated magnetic beads. A previously selected DNA aptamer (R4-6) that binds to C. parvum oocysts with high affinity and selectivity was rationally truncated into two minimer aptamers (Min_Crypto1 and Min_Crypto2), and conjugated to micro-magnetic beads. In flow cytometry tests with phosphate buffer, river water, and wastewater samples, both the minimers showed improved affinity and specificity toward C. parvum oocysts than the parent R4-6. Moreover, Min_Crypto2 showed higher affinity to its target than the parent aptamer when testing in wastewater, indicating superior binding properties in a complex matrix.Using a fluorescence microplate-based assay, and when incubated with different numbers of oocysts, Min_Crypto2 showed a limit of detection as low as 5 C. parvum oocysts in 300 μL of wastewater. Results described here indicate that Min_Crypto2 has superior specificity and sensitivity for the detection of C. parvum oocysts, and has a strong potential to be used successfully in a sensor.

A highly sensitive method for detecting Cryptosporidium parvum oocysts recovered from source and finished water using RT-PCR directed to Cryspovirus RNA

Sensitive detection of Cryptosporidium oocysts is important because the protozoan can cause clinical infection in humans at extremely low numbers. In the present study, 1.5 × 102, 1.0 × 103, or 1.0 × 104C. parvum oocysts were spiked into 10 l of source or finished water in triplicate followed by recovery using Envirochek HV sampling capsules. One subsample of the recovered oocysts was analyzed by commercial immunofluorescence assay (IFA), while a second subsample was subjected to DNA-RNA extraction, followed by RT-PCR using primers directed to the gene encoding Cryspovirus capsid. IFA analysis of Envirochek filter eluates of finished water detected oocysts at all 3 C. parvum oocyst doses, but only at the 1.0 × 103 and 1.0 × 104 doses in source water. Cryspovirus RT-PCR appeared to offer greater sensitivity than IFA because C. parvum oocysts were detected using this molecular technique in both source and finished water concentrates at all 3 spiking levels. A linear relationship was observed between log oocysts spiking dose and the relative intensity of the Cryspovirus RT-PCR signal for finished water, but not for source water. These data indicate that Cryspovirus RT-PCR is a sensitive method for detecting C. parvum oocysts in source and finished water.

Evaluation of three commercial rapid kits to detect Cryptosporidium parvum in diarrhoeic calf stool

The aim of this study was to evaluate three commercially available rapid immunochromatographic tests for detection of Cryptosporidium parvum antigens in faeces of naturally infected neonatal diarrhoeic calves. FASTest® CRYPTO strip, FASTest® CRYPTO-GIARDIA Strip and TETRASTRIPS® were compared for their sensitivity, specificity, positive predictive value and negative predictive value using a cumulative positivity as gold standard. In addition, the agreement between each test and the gold standard was evaluated by Cohen’s Kappa (k) value. The highest infection rate was observed by FASTest® CRYPTO-GIARDIA Strip (65.15%), followed by FASTest® CRYPTO strip (63.64%) and TETRASTRIPS® (56.06%,). A very good diagnostic performance of all the three tests was observed. FASTest® CRYPTO strip (k = 0.935) and FASTest® CRYPTO-GIARDIA Strip (k = 0.968) had the highest sensitivity (100%) while TETRASTRIPS® (k = 0.875) had the highest specificity (100%). Eimeria spp oocysts were present in six samples but cross-reaction with this protozoan was not observed. These assays were not time-consuming and very easy to perform and to read. Based on our results, we recommend the use of FASTest® CRYPTO strip, FASTest® CRYPTO-GIARDIA Strip or/and TETRASTRIPS® for detection of C. parvum antigens in faeces of neonatal diarrhoeic calves.

Disposable microfluidic micromixers for effective capture of Cryptosporidium parvum oocysts from water samples

BackgroundProtecting drinking water supplies from pathogens such as Cryptosporidium parvum is a major concern for water utilities worldwide. The sensitivity and specificity of current detection methods are largely determined by the effectiveness of the concentration and separation methods used. The purpose of this study is to develop micromixers able to specifically isolate and concentrate Cryptosporidium, while allowing in situ analysis.ResultsIn this study, disposable microfluidic micromixers were fabricated to effectively isolate Cryptosporidium parvum oocysts from water samples, while allowing direct observation and enabling quantification of oocysts captured in the device using high quality immunofluorescence microscopy. In parallel, quantitative analysis of the capture yield was carried out by analyzing the waste from the microfluidics outlet with an Imaging Flow Cytometer. At the optimal flow rate, capture efficiencies up to 96% were achieved in spiked samples.ConclusionsScaled microfluidic isolation and detection of Cryptosporidium parvum will provide a faster and more efficient detection method for Cryptosporidium compared to other available laboratory-scale technologies.

First detection of Cryptosporidium parvum in falcons (Falconiformes): Diagnosis, molecular sequencing, therapeutic trial and epidemiological assessment of a possible emerging disease in captive falcons

Cryptosporidiosis in raptors and falcons is well-known to be caused by Cryptosporidium baileyi and associated mainly with respiratory pathology. This report presents the diagnosis of an atypical cryptosporidiosis event caused by Cryptosporidium parvum, that to the authors’ knowledge, is a case observed for the first time in falcons. Two falcons (Gyrfalcon x Peregrine hybrids) were presented for annual check without any clinical signs. Hematology, biochemistry, fecal and crop parasitology, radiographic and endoscopic examinations were performed. Endoscopy revealed microcystic formation of the caudal lung field in the two falcons, adhesions and air sac alterations. Sampling and subsequent cytology revealed fungal spores and acid fast stain organisms (identified as Cryptosporidium spp.). Feces and affected lung tissue was further send for Cryptosporidium spp.-DNA detection. Fecal samples and lung tissue tested positive for Cryptosporidium spp. gp60 gene by PCR. By sequence analysis of the gp60 gene locus, diagnosis of C. parvum was confirmed with 100% homology. Despite the fact that falcons didn’t recover after 1 month of therapy, eight months after the initial examination they were clinically healthy and had satisfactory flying performance. No other falcons were observed with C. parvum infections in the facility so far. The possible source, infection route and implications are discussed.

An overview of methods/techniques for the detection of Cryptosporidium in food samples.

Cryptosporidium is one of the most important parasitic protozoa of concern within the food production industry, worldwide. This review describes the evolution and its development, and it monitors the methodology that has been used for Cryptosporidium in food material since 1984, when the first publication appeared regarding the detection of Cryptosporidium parvum in food materials. The methods that are currently being used for the detection of Cryptosporidium oocysts in food material (mainly vegetables) and all of the other available published methods are discussed in this review. Generating more consistent and reliable data should lead to a better understanding of the occurrence, transport and fate of the oocysts in food material. Improvements in monitoring and developing effective methodology, along with food security, offer more practical possibilities for both the developed and developing worlds.

RT-PCR specific for Cryspovirus is a highly sensitive method for detecting Cryptosporidium parvum oocysts

Cryptosporidium parvum represents a considerable health risk to humans and animals because the parasite has a low infectious dose and is usually present at low numbers in environmental samples, which makes detection problematic. The purpose of this study was to evaluate Cryspovirus as a target for sensitive detection of C. parvum in clinical samples. Semi-quantitative RT-PCR (sqRT-PCR) and quantitative RT-PCR (qRT-PCR) directed to Cryspovirus sequences could detect less than 5 Cryptosporidium oocysts in RNA extracted from C. parvum-containing calf feces. Of interest was that a similar level of sensitivity was observed using RNA present in DNA extracts of the same C. parvum fecal samples. There was a strong correlation between both the sqRT-PCR and qRT-PCR product and number of C. parvum oocysts. Analysis of DNA extracted from a similar number of oocysts using PCR targeting the Cryptosporidium SSU rDNA gene sequence found that nested PCR was necessary to obtain a detectable PCR signal. The availability of DNA allowed for Cryptosporidium genotyping based on SSU rDNA sequencing as well as C. parvum subtyping through GP60 sequencing. By using DNA that contains viral RNA, the assay avoids two separate extractions — one for RNA and one for DNA. This two-step assay, first to detect Cryptosporidium by Cryspovirus-specific RT-PCR followed by nested SSU rDNA PCR for Cryptosporidium genotyping may represent an important tool for identifying the parasite in clinical samples.

Evaluation of alternative DNA extraction processes and real-time PCR for detecting Cryptosporidium parvum in drinking water

USEPA Method 1623 is the standard method in the United States for the detection of Cryptosporidium in water samples, but quantitative real-time polymerase chain reaction (qPCR) is an alternative technique that has been successfully used to detect Cryptosporidium in aqueous matrices. This study examined various modifications to a commercial nucleic acid extraction procedure in order to enhance PCR detection sensitivity for Cryptosporidium. An alternative DNA extraction buffer allowed for qPCR detection at lower seed levels than a commercial extraction kit buffer. In addition, the use of a second spin column cycle produced significantly better detection (P = 0.031), and the volume of Tris–EDTA buffer significantly affected crossing threshold values (P = 0.001). The improved extraction procedure was evaluated using 10 L of tap water samples processed by ultrafiltration, centrifugation and immunomagnetic separation. Mean recovery for the sample processing method was determined to be 41% using microscopy and 49% by real-time PCR (P = 0.013). The results of this study demonstrate that real-time PCR can be an effective alternative for detecting and quantifying Cryptosporidium parvum in drinking water samples.

Efficacy of some laboratory methods in detecting giardia lamblia and cryptosporidium parvumin stool samples

Background: Giardia duodenalis and Cryptosporidium parvum are the most prevalent intestinal parasites of human. It also infects a wide range of mammals .Two genotype of G.duodenalis (A and B) were commonly reported among humans with different frequency of distribution in different geographical locations. Methods :total of 434 stool samples were collected from peoples in kikrkuk city during October 2012toAugust 2013. Zinc sulphate flotation technique was applied on 226 positive stool, serological methods involve Giardia ELISA-corpo antigen, Direct fluorescent assay (DFA), and lateral immune-chromatography assay(Triage panel) .Extractions of Giardia genome DNA from stool samples were performed using QIAamp Stool Mini kit with a modified protocol. PCR- one step procedure was used to amplify a fragment of Giardia lamblia genome using k725 gene locus,(Mixture primers of human A and B assemblages) Results:The overall rate of intestinal parasitic infection was 52.07%,Giardia lamblia rate was 24.65%.Common isolated parasites were Cryptosporidium parvum ,Blastocystishominis, other intestinal protozoan parasites and nematode helminthes:7.60 & 5.76 %,7.37 and 6.68 % respectively. Sensitivity and specificity of PCR method and direct microscopy were higher than other four methods used for detecting giardiasis. Triage panel method exert high rate of giardiasis than revealing of Cryptosporidium and Entamoeba histolytica. From the application of five methods for Cryptosporidium diagnosis, DFA and modified Ziehl-Neelsen(MZN) methods show high sensitivity and specificity than other three methods. Application of PCR single step using mixture primers assemblages A and B, show high rate of sensitivity than other methods in detecting giardiasis.Amplified Giardia genome length extended from 220 to 750 bps with mean of 437.56 bps. Conclusions: PCR assay targeting K725 gene locus is a sensitive tool and discriminates mixed genotypes of G.lamblia. DFA and MZN are sensitive tools for detecting Cryptosporidium parvum in stool samples

English

Diarrheal diseases are very common in children under 5 years and may lead to a delay of physical and mental development. Despite this knowledge, data on diarrheal diseases and socioeconomic determinants are still scarce in Côte d’Ivoire. This study is then conducted with the objective to fill part of this gap and specifically assess link between infant diarrhea occurrence and some major socio-environmental factors. Stool samples were collected from children less than five suffering from diarrhea at Yamoussoukro Regional Hospital in central Côte d’Ivoire. Molecular species specific diagnosis was used to detect Cryptosporidium parvum, Giardia intestinalis and Entamoeba histolytica, three major protozoan parasites which cause diarrhea. Out of 306 stool samples examined, 62.75% were detected as positive at least for one of the protozoan parasite studied. Species specific prevalence was 36.93% for C. parvum, 20.92% for G. intestinalis and 22.55% for E. histolytica. Infection was more prevalent in children whose mothers were not educated although the difference was not statistically significant. No link was found between gender and infection while sanitation infrastructures, mother and children ages and water sources were found significantly associated with diarrhea occurrence. Awareness is then needed for women on lack of hygiene rules that could lead to diarrheal diseases burden. Key words: Diarrheal diseases, children development, parasitic protozoan, molecular characterization, socio-environmental factors.

A multiattribute utility evaluation for the detection of Cryptosporidium species in stool

A total of 500 stool samples were subjected to examination with the help of direct microscopy and concentration methods. Of these, fifty two (10.4%) specimens were positive for Cryptosporidium parvum. Among direct microscopy methods - direct wet mount, negative staining and modified Ziehl-Neelsen staining showed a positivity of 22 (4.4%), 14 (2.8%) and 39 (7.8%) respectively. After the Formol-ether Concentration (FEC) technique, wet mount, negative staining and modified Ziehl-Neelsen stain were positive in 32 (6.4%), 37 (7.4%) and 52 (10.4%) cases respectively. Wet mount after Saturated Sodium Chloride Salt Flotation (SSSF) technique was positive in only 6 (1.2%) cases. Modified Ziehl-Neelsen stain after SSSF technique was positive in 19 (3.8%) cases while negative staining after SSSF technique was positive in only 1 (0.2%) case. Cryptosporidium parvum positivity was 1.18 times higher in males as compared to females. The results indicate that the modified Ziehl-Neelsen staining after FEC technique to detect Cryptosporidium parvum in the stool specimens has significantly higher accuracy (p<0.001) and reliability as compared to all the other techniques.

Detection of multiple waterborne pathogens using microsequencing arrays

A microarray was developed to simultaneously detect Cryptosporidium parvum, Cryptosporidium hominis, Enterococcus faecium, Bacillus anthracis and Francisella tularensis in water. A DNA microarray was designed to contain probes that specifically detected C.parvum, C.hominis, Ent.faecium, B.anthracis and F.tularensis. The microarray was then evaluated with samples containing target and nontarget DNA from near-neighbour micro-organisms, and tap water spiked with multiple organisms. Results demonstrated that the microarray consistently detected Ent.faecium, B.anthracis, F.tularensis and C.parvum when present in samples. Cryptosporidium hominis was only consistently detected through the use of shared probes between C.hominis and C.parvum. This study successfully developed and tested a microarray-based assay that can specifically detect faecal indicator bacteria and human pathogens in tap water. The use of indicator organisms has become a practical solution for monitoring for water quality. However, they do not always correlate well with the presence of many microbial pathogens, thus necessitating direct monitoring for most pathogens. This microarray can be used to simultaneously detect multiple organisms in a single sample. More importantly, it can provide occurrence information that may be used in assessing potential exposure risks to waterborne pathogens.

Detecting Cryptosporidium parvum and Giardia lamblia by coagulation concentration and real-time PCR quantification

Rapid and sensitive pathogen detection methods are essential for the effective functioning of the water treatment industry, yet for many pathogens, effective detection and removal methods are still lacking. Cryptosporidium parvum oocysts and Giardia lamblia cysts are two of the most common waterborne pathogens currently infecting the water supply. In this study, a new method was developed for the detection of Cryptosporidium parvum oocysts and Giardia lamblia cysts. The method includes multi-steps as coagulation concentration of (oo)cysts in water, the dissolution of the resulting flocs into a small volume using acid, filtration of the (oo)cysts solution, and DNA extraction, purification, and examination using real-time PCR. The method was tested using spiked tap water and reservoir water as references, and the mean recovery ranged from 19.6% to 97.6% for oocysts, and from 51.4% to 98.7% for cysts. The method is economical and convenient, and is especially suitable for relatively high turbidity surface water.

Field-deployable and near-real-time optical microfluidic biosensors for single-oocyst-level detection of Cryptosporidium parvum from field water samples

Cryptosporidium spp. is an obligate, parasitic protozoan that is difficult to detect and causes diarrhea in healthy adults while potentially causing death in the immunocompromised and children. Its treatment options are few and treat the symptoms, not the actual parasite. Current methods of detection are inefficient and rely too heavily upon laboratory sample preparations and technician skill, including differential staining, negative staining, and immunofluorescence methods [especially U.S. Environmental Protection Agency (EPA) Method 1623]. These assays can take from hours to days and require a laboratory environment. In this work, we demonstrated the microbead immunoagglutination assay combined with Mie scatter detection in a microfluidic device to provide a field-deployable and near-real-time alternative to the laboratory-based method (especially EPA Method 1623). Two main challenges were the relatively big diameter of Cryptosporidium oocysts (5-6 μm) and the contaminants in field water samples that negatively affected the immunoagglutination and its scatter detection. We used 4 min sonication to liberate Cryptosporidium oocyst wall proteins (COWP), which was previously used to inactivate Cryptosporidium oocysts. As for the contaminants, we optimized the microbead diameter (920 nm) and the wavelength of incident light (375 nm) to find the angle of scatter detection (45°) where the Mie scatter from immunoagglutinated microbeads was maximum and the background scatter from contaminants was minimum. This enabled the sub-single-oocyst-level detection despite the fact that only a very small volume of water sample (15 μL) was introduced to the microfluidic biosensor. When combined with filtration/concentration, this method is able to detect ≤1 oocyst per large volume of water, comparable to or potentially better than the EPA method 1623, while effectively reducing the time and labor necessary for staining and microscopic analysis. For faster, near-real-time assays, filtration/concentration may not be used, where the detection limit was 1-10 oocysts per mL with the total assay time of 10 min including the 4 min sonication time. The linear range of assay was over 5 orders of magnitude. The final device was compact and had the potential to be used in field situations, and required less technical expertise and/or training compared to the other methods.

Detection of Cryptosporidium parvum and Cryptosporidium hominis in human patients in Cairo, Egypt

Cryptosporidium is a significant cause of diarrheal disease in developing and industrialized nations. Cryptosporidium hominis and Cryptosporidium parvum are the main agents of cryptosporidiosis in humans. In Egypt, very little is known about genetic structure of Cryptosporidium spp. Therefore, this study was designed to examine samples from sporadic cases of cryptosporidiosis in Egyptians in order to identify the species involved in infection as well as the transmission dynamics and distribution of the parasite in the Great Cairo area. A total of 391 human faecal samples were collected, between May 2008 and March 2009, from ten public hospitals in Great Cairo. Initial screening by immunochromatographic detection kit "the Stick Crypto-Giardia; Operon" showed 23 possible positive cases. Twenty of them were confirmed by microscopic examination. PCR was performed by amplification of the oocyst wall protein (COWP) gene where 18 out of 23 samples were positive, one not detected by microscopy. Cryptosporidium genotyping was performed by RFLP analysis of PCR products of the diagnosis PCR. Only 15 samples rendered a digestion pattern. The genotyping distribution was nine cases showing C. hominis genotype, three showing C. parvum genotype and three showing mixed infection by C. hominis and C. parvum. The data showed an elevated prevalence of C. hominis (80.0%), the most anthroponotic species, suggesting a human-human transmission. Furthermore, the presence of up to 40% of samples infected with C. parvum shows that further investigations are required to determine the subgenotypes of C. parvum to clarify the mode of transmission in order to improve the control measures.