OBJECTIVETo simultaneously detect viable Cryptosporidium parvum oocysts and Giardia duodenalis cysts for the purpose of reducing time and cost spent.

METHODSA duplex reverse transcription polymerase chain reaction (RT-PCR) method was newly developed.

RESULTSUsing duplex RT-PCR method for the hsp70 gene, viable (oo)cyst concentrations of 10(1) and 10(3) (oo)cysts/100 microL could be detected for C. parvum and G duodenalis, respectively. However, after heat-shock stimulation the expression of hsp70 mRNAs was detectable at 10(0) and 10(1) (oo)cysts/100 microL concentrations of C. parvum and G duodenalis, respectively. Thus, the detection sensitivity was significantly increased when the viable (oo)cysts were exposed to heat shock.

CONCLUSIONThis study describes a new duplex RT-PCR method for hsp70 gene to detect the viable (oo)cysts of the C. parvum and G duodenalis with less time consumed and at a lower cost. This newly developed duplex RT-PCR method may be used to detect these parasites not only in aquatic environments but also in clinical samples.

To understand the distribution of Giardia cysts in drinking water supplies in Seoul, Korea, we collected water samples quarterly at 6 intakes in the Han River, its largest stream and 6 conventional water treatment plants (WTPs) serving drinking water, from 2000 to 2009. Giardia cysts in each of 10 L water were confirmed in 35.0% of intake water samples and the arithmetic mean was 1.65 cysts/10 L (range 0-35 cysts/10 L). The lowest cyst density was observed at Paldang and Kangbuk intakes, and the pollution level was higher at 4 intakes downstream. It seemed that these 4 intakes were under influence of Wangsuk stream at the end of which cysts were found in all samples with the mean of 140 cysts/10 L. The annual mean number of cysts was 0.21-4.21 cysts/10 L, and the cyst level at the second half of the 10 years was about 1/5 of that at first half on average. The cysts were more frequently found in winter, and their mean density was 3.74 cysts/10 L in winter and 0.80-1.08 cysts/10 L in other seasons. All finished water samples collected at 6 WTPs were negative for Giardia in each of 100 L sample for 10 years and cyst removal by physical process was average 2.9-log. It was concluded that conventional water treatment at 6 WTPs of Seoul appears to remove the cysts effectively under the present level of their source water. Domestic wastewater from the urban region could be an important source of Giardia pollution in the river.
Fresh Water/*parasitology ; Giardia/growth & development/*isolation & purification ; Republic of Korea ; Rivers/parasitology ; Seasons ; Water Supply/*analysis

The status of intestinal parasitic infections and seroprevalence of cystic echinococcosis in the inhabitants in Dornod and Selenge, Mongolia, was observed with stool and serum samples from 165 and 683 residents from August 9 to August 15, 2003. A total of 10 inhabitants (6.1%) were found to be infected with protozoan cysts or oocysts by stool examinations; 7, 1 and 2 cases with Entamoeba coli, Giardia lamblia and Cryptosporidium parvum, respectively. A total of 62 people (9.1%) revealed significantly high levels of specific antibodies against Echinococcus granulosus by enzyme-linked immunosorbent assay (ELISA). The surveyed areas are rural areas and the sanitized tab water is not available. There is a possibility of endemic transmission of water-borne protozoan diseases in these areas. The clinical echinococcosis is needed to be searched from the seropositive inhabitants.
Protozoan Infections/*epidemiology/parasitology ; Mongolia/epidemiology ; Humans ; Giardia lamblia/isolation & purification ; Gastrointestinal Diseases/*epidemiology/*parasitology ; Entamoeba/isolation & purification ; Echinococcosis/*epidemiology ; Cryptosporidium parvum/isolation & purification ; Animals

Child ; Epstein-Barr Virus Infections ; complications ; Female ; Giardia lamblia ; isolation & purification ; Giardiasis ; complications ; Herpesvirus 4, Human ; isolation & purification ; Humans ; Lymphohistiocytosis, Hemophagocytic ; drug therapy ; etiology

We aimed to assess the risks of
China ; Cryptosporidiosis/microbiology* ; Cryptosporidium/isolation & purification* ; Giardia/isolation & purification* ; Giardiasis/microbiology* ; Humans ; Risk Assessment ; Water Microbiology ; Water Supply/statistics & numerical data*

The aim of this study was to relate personal data, socio-cultural and environmental characteristics, and the presence of symptoms/signs with the frequencies of Giardia spp. and Blastocystis hominis among a rural population in Buenos Aires Province, Argentina. Of the surveyed population (350), 3.7% were infected with only Giardia spp. or 22.9% with B. hominis, and 2.3% were infected with both protozoa. The frequency of infection according to sex; 6.1% of males were infected and 1.6% of females by Giardia spp., 26.7% and 19.5% by B. hominis, and 2.4% and 2.2% by both parasites, respectively. Giardia spp. was detected in only three adults (over 14 years), but B. hominis was more frequent in adults than in children. The prevalences of these protozoa in this community are lower than those reported by other Argentinean studies, which is probably associated with the low density of the studied population (5.95 inhab/km2). Statistical analysis revealed that a male sex, flooding of the home, the use of a latrine, and an abdominal pain were correlated with the presence of these parasites, which indicate the importance of these factors in rural communities.
Adolescent ; Adult ; Age Factors ; Animals ; Argentina/epidemiology ; Blastocystis Infections/*epidemiology ; Blastocystis hominis/*isolation & purification ; Child ; Feces/parasitology ; Female ; Giardia/isolation & purification ; Giardiasis/*epidemiology ; Health Surveys ; Humans ; Hygiene ; Male ; Population Density ; Prevalence ; Research Support, Non-U.S. Gov't ; Rural Population ; Sex Factors

Giardia intestinalis infections arise primarily from contaminated food or water. Zoonotic transmission is possible, and at least 7 major assemblages including 2 assemblages recovered from humans have been identified. The determination of the genotype of G. intestinalis is useful not only for assessing the correlation of clinical symptoms and genotypes, but also for finding the infection route and its causative agent in epidemiological studies. In this study, methods to identify the genotypes more specifically than the known 2 genotypes recovered from humans have been developed using the intergenic spacer (IGS) region of rDNA. The IGS region contains varying sequences and is thus suitable for comparing isolates once they are classified as the same strain. Genomic DNA was extracted from cysts isolated from the feces of 5 Chinese, 2 Laotians and 2 Koreans infected with G. intestinalis and the trophozoites of WB, K1, and GS strains cultured in the laboratory, respectively. The rDNA containing the IGS region was amplified by PCR and cloned. The nucleotide sequence of the 3' end of IGS region was determined and examined by multiple alignment and phylogenetic analysis. Based on the nucleotide sequence of the IGS region, 13 G. intestinalis isolates were classified to assemblages A and B, and assemblage A was subdivided into A1 and A2. Then, the primers specific to each assemblage were designed, and PCR was performed using those primers. It detected as little as 10 pg of DNA, and the PCR amplified products with the specific length to each assemblage (A1, 176 bp; A2, 261 bp; B, 319 bp) were found. The PCR specific to 3 assemblages of G. intestinalis did not react with other bacteria or protozoans, and it did not react with G. intestinalis isolates obtained from dogs and rats. It was thus confirmed that by applying this PCR method amplifying the IGS region, the detection of G. intestinalis and its genotyping can be determined simultaneously.
Sequence Analysis, DNA ; Sensitivity and Specificity ; Polymerase Chain Reaction/*methods ; Phylogeny ; Mice ; Humans ; Giardiasis/parasitology/veterinary ; Giardia lamblia/*classification/genetics/*isolation & purification ; Genotype ; Dogs ; Dog Diseases/parasitology ; DNA, Ribosomal Spacer/*analysis ; DNA, Protozoan/*analysis/isolation & purification ; Base Sequence ; Animals

The cyclophilins (Cyps) are family members of proteins that exhibit peptidylprolyl cis-trans isomerase (PPIase, EC 5.2.1.8) activity and bind the immunosuppressive agent cyclosprin A (CsA) in varying degrees. During the process of random sequencing of a cDNA library made from Giardia intestinalis WB strain, the cyclophilin gene (gicyp 1) was isolated. An open reading frame of gicyp 1 gene was 576 nucleotides, which corresponded to a translation product of 176 amino acids (Gicyp 1). The identity with other Cyps was about 58-71%. The 13 residues that constituted the CsA binding site of human cyclophilin were also detected in the amino acid sequence of Gicyp 1, including tryptophan residue essential for the drug binding. The single copy of the gicyp 1 gene was detected in the G. intestinalis chromosome by southern hybridization analysis. Recombinant Gicyp 1 protein clearly accelerated the rate of cis-- Amino Acid Sequence ; Animals ; Cloning, Molecular ; Cyclophilins/antagonists & inhibitors/chemistry/genetics/*isolation&purification ; Cyclosporine/metabolism/pharmacology ; Giardia lamblia/*chemistry/genetics ; Human ; Immunosuppressive Agents ; Molecular Sequence Data ; Protein Binding ; Protozoan Proteins ; Recombinant Proteins

An epidemiological study on canine intestinal parasites was undertaken to evaluate changes in the prevalence among private household dogs from the Hachinohe region of Aomori prefecture, Japan, in 1997, 2002 and 2007, using the formalin-ethyl acetate sedimentation technique. The risk of zoonotic transmission from household dogs to humans was also discussed. All intestinal parasites detected in the present study (Giardia intestinalis, Isospora spp., Toxocara canis, Ancylostoma caninum, Trichuris vulpis and Strongyloides stercoralis) showed no changes in prevalence over the past 10 years based on analysis considering canine epidemiological profiles. In particular, prevalence of Giardia intestinalis in dogs under 1 year old, derived from pet shops/breeding kennels and kept indoors was unchanged, remaining at a high level of >15.0% at each time point. Toxocara canis also showed no changes in the group of dogs under 1 year old, bred by private owners and kept outdoors, and the prevalence was >10.0% every year. The present results indicate that the prevalence of Giardia intestinalis and other intestinal parasites in private household dogs has not always decreased, and the potential for direct parasitic zoonotic transmission from dogs to humans may be relatively high level, than from the environment (indoors and outdoors). We recommend careful surveillance of intestinal parasites and aggressive use of anthelminthic in private household dogs under considering the epidemiological factors.
Animal Husbandry ; Animals ; Anthelmintics/*therapeutic use ; Dog Diseases/drug therapy/epidemiology/*parasitology ; Dogs ; Giardia lamblia/*isolation & purification ; Humans ; Intestinal Diseases, Parasitic/drug therapy/epidemiology/parasitology/*veterinary ; Japan/epidemiology ; Parasitic Diseases, Animal/drug therapy/epidemiology/*parasitology ; Prevalence ; Time Factors ; Zoonoses

Giardia is a major public health concern and considered as reemerging in industrialized countries. The present study investigated the prevalence of giardiosis in 202 sheltered dogs using PCR. The infection rate was 33.2% (67/202); Gyeongsangbuk-do and Daejeon showed 25.7% (39/152, P<0.0001) and 56% (28/50), respectively. The prevalence of infected female dogs (46.7%, P<0.001) was higher than in male dogs (21.8%). A higher prevalence (43.5%, P<0.0001) was observed in mixed breed dogs than purebred (14.1%). Although most of the fecal samples collected were from dogs of > or =1 year of age which showed only 27.4% positive rate, 61.8% (P<0.001) of the total samples collected from young animals (<1 year of age) were positive for G. intestinalis. A significantly higher prevalence in symptomatic dogs (60.8%, P<0.0001) was observed than in asymptomatic dogs (23.8%). Furthermore, the analysis of nucleotide sequences of the samples revealed that G. intestinalis Assemblages A and C were found in the feces of dogs from Gyeongsangbuk-do and Daejeon. Since G. intestinalis Assemblage A has been known to infect humans, our results suggest that dogs can act as an important reservoir of giardiosis in Korea. Hence, hygienic management should be given to prevent possible transmission to humans.
Animals ; Base Sequence ; Dog Diseases/epidemiology/*parasitology ; Dogs ; Feces/parasitology ; Female ; Genotype ; Giardia/classification/genetics/*isolation & purification ; Giardiasis/epidemiology/parasitology/*veterinary ; Male ; Molecular Sequence Data ; Protozoan Proteins/genetics ; Republic of Korea/epidemiology