• Parasites, Hosts and Diseases
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• v.33 no.3
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• pp.155-164
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• 1995

The location of actin and myosin of the several stages of Cwptosporinium parvum was observed. The tissue antigen of C. pcruum was prepared through immunosuppression of IgG mice with Depomedrol . The thin sectioned specimens, which were incubated with the IgG fraction of the rabbit polyclonal antibodies raised against chicken back muscle actin and bovine uterus myosin, were treated with 10 nm gold-conjugated goat anti-rabbit IgG, Electrodense particles were located mainly on the pellicles of all observed developmental stages of the parasites. The number of actin gold particles in the cytoplasm increased when the parasite was dividing actively as in case of meronts. Especially in macrogametocytes, a lot of actin and myosin particles were synthesized and storaged as amilopectin-like bodies. There were many actin gold particles along the microspikes of cytoplasmic membranes in various developmental stages. The actin and myosin observed in this study may play important roles to control the shape of the parasites and movement of cytoplasmic membranes as cvtoskeletal proteins.

• Parasites, Hosts and Diseases
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• v.29 no.2
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• pp.149-160
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• 1991

Each of SPF mice(Scl: ICR strain, 3-week-old males) was inoculated with 5$\times$104 oocysts of Cryptosporidium by stomach tube. The oocysts were large type one which was previously isolated from Korean mice, and passaged in 3-week-old SPF mice. The patterns of oocyst discharge were monitored daily, and in order to observe the ultrastructure of developmental stages the stomach of the mice was examined by transmission electron microscopy (TEM) at 4 weeks post-inoculation. The prepatent period for 6 mice was 5.6 days post-inoculation on the average, and the patent period was 63.2 days. The number of oocysts discharged per day from the mice reached peak on day 36.6 post-inoculation on the average. A large number of oocysts were found in fecal samples obtained from inoculated mice on days 30~50 post-inoculation. C. tsuris was larger than C. parvum at almost every developmental stages, the sixte difference being 1.4 times in oocysts, 2.4 times in sporozoites, 1.6 times in merozoites, and 1.5 times in microgametes. The ultrastructural features of the attachment site of C. tsuris to the mucus cells were remarkably different from those of C. parvum and its closely related species. The anterior projection of the protozoa (C. muris), the outer aspect of which was surrounded by a thick filamentous process of the host cell, has not been reported at any developmental stages of C. parvum or its closely related species. The size of the oocysts of strain RN 66 was larger than that of Korean mice origin. The above results reveal that the large type Cryptosporidium of Korean mice origin is identified as Cryptosporidium muris and this type was named as C. muris (strain MCR).

• Parasites, Hosts and Diseases
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• v.47 no.3
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• pp.219-225
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• 2009

The seroprevalence of cryptosporidiosis was examined using patients' sera collected from hospitals located in 4 different areas of the Republic of Korea. ELISA was used to measure antibody titers against Cryptosporidium parvum antigens from a total of 2,394 serum samples, which were collected randomly from patients in local hospitals; 1)Chungbuk National University Hospital, 2) Konkuk University Hospital, 3) local hospitals in Chuncheon, Gangwon-do (province), 4) Jeonnam National University Hospital, from 2002 through 2003. Of the2,394 samples assayed, 34%, 26%, and 56% were positive for C. parvum-specific IgG, IgM, and IgA antibodies, respectively, Positive IgG titers were most common in sera from Jeonnam National University Hospital, Gwangju, Jeollanam-do, and positive IgM titers were most common in sera from Chungbuk National University Hospital, Cheongju, Chuncheonqbuk-do. The seropositivity was positively correlated with age for both the IgG and IgA antibodies but was negatively correlated with age for the IgM antibodies. Western blotting revealed that 92%, 83%, and 77% of sera positive for IgG, IgM, and IgA ELISA reacted with 27-kDa antigens, respectively. These results suggested that infection with Cryptosporidium in hospital patients occurs more commonly than previously reported in the Republic of Korea.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.4
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• pp.368-371
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• 2006

The standard procedure outlined by the United States Environmental Protection Agency (US EPA) in Method 1623 for analyzing Giardia lamblia cysts and Cryptosporidium parvum oocysts in water samples consists of filtration, elution, centrifugal concentration, immunomagnetic separation (IMS), and immunofluorescence assay (IFA) followed by microscopic examination. In this study, the extent of (oo)cyst loss in each step of this procedure was evaluated by comparing recovery yields in segmented analyses: (i) IMS + IFA, (ii) concentration + IMS + IFA, and (iii) filtration/elution + concentration + IMS + IFA. The complete (oo)cyst recovery by the full procedure was $52{\sim}57%$. The (oo) cyst loss in the IMS step was only $0{\sim}6%$, implying that IMS is a fairly reliable method for (oo)cyst purification. Centrifugal concentration of the eluted sample and pellet collection before IMS resulted in a loss of $8{\sim}14%$ of the (oo)cysts. The largest (oo)cyst loss occurred in the elution step, with $68{\sim}71%$ of the total loss. The permeated loss of (oo)cysts was negligible during filtration of the water sample with a $1.0-{\mu}m$ pore polyethersulfone (PES) capsule. These results demonstrated that the largest fraction of (oo)cyst loss in this procedure occurred due to poor elution from the filter matrix. Improvements in the elution methodology are therefore required to enhance the overall recovery yield and the reliability of the detection of these parasitic protozoa.

• The Microorganisms and Industry
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• v.16 no.2
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• pp.2-9
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• 1990

This paper outlines research to study two aspects of Cryptooridium. First, specific antigenic determinants were identified and followed through the growth cycle of C. parvum to investigate antigenic sharing of molecular epitopes among the different life cycle stages. Secondly, the importance of passive immune protective mechanisms in cryptosporidial infection was assessed by following the course of infection in neonatal mice which have been subjected to treatments using either monoclonal antibodies (mAbs) or hyperimmune bovine colostrum.

• Parasites, Hosts and Diseases
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• v.59 no.4
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• pp.409-413
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• 2021

In this study, we have collected and screened a total of 268 stool samples from diarrheal patients admitted to an Infectious disease hospital in Kolkata for the presence of Cryptosporidium spp. The initial diagnosis was carried out by microscopy followed by genus specific polymerase chain reaction assays based on 70 kDa heat shock proteins (HSP70). DNA sequencing of the amplified locus has been employed for determination of genetic diversity of the local isolates. Out of 268 collected samples, 12 (4.48%) were positive for Cryptosporidium spp. Sequences analysis of 70 kDa heat shock proteins locus in 12 Cryptosporidium local isolates revealed that 2.24% and 1.86% of samples were showing 99% to 100% identity with C. parvum and C. hominis. Along with the other 2 major species one recently described globally distributed pathogenic species Cryptosporidium viatorum has been identified. The HSP70 locus sequence of the isolate showed 100% similarity with a previously described isolate of C. viatorum (Accession No. JX978274.1, JX978273.1, and JN846706.1) present in GenBank.

• Journal of Microbiology
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• v.41 no.2
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• pp.148-151
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• 2003

Waterborne parasite infections are considered a reemerging threat. Most studies on the epidemiology of human cryptosporidiosis, giardiasis, and amebiasis have been carried out in developed countries, and there is little data on the occurrence of these infections in other areas. The objective of this study was to investigate the presence of waterborne parasites such as Cryptosporidium parvum, Giardia lamblia and Entamoeba histolytica in various water samples in Ankara, turkey. A total of 85 samples were examined, 43 from the municipal water supply, 34 from wells, 6 from the Ankara River, and 2 from two untreated dams; by conventional microscopy, immunologically and by polymerase chain reaction (PCR). Oocysts of C. parvum and cysts of G. lamblia were detected by using an indirect fluorescence (antigen) assay, whereas an enzyme linked immunosorbent assay was used to detect the cysts of E. histolytica and E. dispar. In addition, PCR was used for E. histolytica, E. dispar, C. parvum and G. lamblia detection. G. lamblia was found in 2 of the 34 well water samples, and parasites were found in 3 of the 6 Ankara River samples. The 1$\^$st/ contained E. histolytica cysts and Strongyloides stercoralis larvae. the 2$\^$nd/ E. histolytica cysts, and Trichuris trichiura eggs, and the 3$\^$rd/ C. parvum oocysts only. No parasite was observed in the municipal water samples and untreated dam water samples. These results extend our knowledge on waterborne parasites, such occurrence information on waterborne pathogens assists the management and treatment of municipal water.

• Parasites, Hosts and Diseases
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• v.48 no.2
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• pp.105-111
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• 2010

To understand the situation of water contamination with Cryptosporidium spp. and Giardia spp. in the northern region of Portugal, we have established a long-term program aimed at pinpointing the sources of surface water and environmental contamination, working with the water-supply industry. Here, we describe the results obtained with raw water samples collected in rivers of the 5 hydrographical basins. A total of 283 samples were analyzed using the Method 1623 EPA, USA. Genetic characterization was performed by PCR and sequencing of genes 18S rRNA of Cryptosporidium spp. and $\beta$-giardin of Giardia spp. Infectious stages of the protozoa were detected in 72.8% (206 of 283) of the water samples, with 15.2% (43 of 283) positive for Giardia duodenalis cysts, 9.5% (27 of 283) positive for Cryptosporidium spp. oocysts, and 48.1% (136 of 283) samples positive for both parasites. The most common zoonotic species found were G. duodenalis assemblages A-I, A-II, B, and E genotypes, and Cryptosporidium parvum, Cryptosporidium andersoni, Cryptosporidium hominis, and Cryptosporidium muris. These results suggest that cryptosporidiosis and giardiasis are important public health issues in northern Portugal. To the authors' knowledge, this is the first report evaluating the concentration of environmental stages of Cryptosporidium and Giardia in raw water samples in the northern region of Portugal.

• Parasites, Hosts and Diseases
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• v.57 no.2
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• pp.197-200
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• 2019

Cryptosporidium is a common intestinal protozoan that can lead to diarrhea in humans and dogs. The predominant species of infection are C. hominis and C. parvum in humans, and C. canis in dogs. However, C. canis can infect immunocompromised humans. Considering the close contact with humans, dogs have the potential to be reservoirs for human cryptosporidiosis. Breeding kennels are the major supply source of puppies for pet shops. The present study is to determine the molecular prevalence and characteristics of Cryptosporidium spp. found in breeding kennel dogs. A total of 314 fecal samples were collected from young and adult dogs kept in 5 breeding kennels. A polymerase chain reaction targeting the small subunit rRNA gene was employed for the detection of Cryptosporidium spp. To determine the species, the DNA sequences were compared to GenBank data. Overall, 21.0% of the fecal samples were positive for Cryptosporidium spp. infection. Cryptosporidium spp. was detected in all 5 facilities. A sequencing analysis demonstrated that all isolates shared 99-100% similarity with C. canis. The results suggest that Cryptosporidium spp. infection is present at a high-level in breeding kennel dogs. However, because dominant species in this survey was C. canis, the importance of breeding kennel dogs as reservoirs for Cryptosporidium spp. transmission to humans is likely to be low in Japan.

• Parasites, Hosts and Diseases
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• v.55 no.2
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• pp.129-135
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• 2017

A total of 60 samples were collected from 35 swimming pools in Beijing, China, and the presence of Cryptosporidium and Giardia were investigated. The results showed that 16.7% and 15.0% of samples were positive for Cryptosporidium oocyst and Giardia cysts, respectively, with a mean concentration of 0.30 oocysts/10 L and 0.27 cysts/10 L. The oocysts and cysts were found to have higher rates of occurrence in August than in May. Genotyping confirmed the presence of Cryptosporidium hominis, C. parvum, and Giardia assemblages A and B, all of which were associated with human infections. The predominant species/assemblages were C. hominis and Giardia assemblage A. Analyses of the relationships between parasite oocysts/cysts, indicator bacteria, and physical-chemical parameters revealed that there was no correlation between 2 parasites and fecal bacterial indicators, whilst there was a significant correlation between protozoa and urea concentration, which indicates that urea concentration rather than fecal bacterial indicators might be an appropriate index for chlorine-resistant protozoa in swimming pools. This study provides useful information to improve the safety of swimming pool water and deduce the risk of protozoan infections.