Prevalence and genetic characterization of Cryptosporidium in yaks in Qinghai Province of China

Study on genetic characteristics of Cryptosporidium isolates and first report of C. parvum IIdA24G2 subtype in dairy cattle in China

Cryptosporidium is an important gastrointestinal parasite that can cause mild to severe diarrhea in various vertebrates, including humans and domestic animals. Infection is prevalent in dairy cattle, particularly calves, resulting in diarrhea and increased mortality with significant production losses. However, the prevalence and identity of Cryptosporidium spp. in cattle in Heilongjiang Province is still poorly known. Our study aimed to investigate the prevalence and species and subtype distribution of Cryptosporidium in cattle in the region. In addition, we evaluated the zoonotic potential of Cryptosporidium isolates and assessed possible transmission routes and health effects of this organism. We collected 909 fecal samples from five different farms in Heilongjiang Province between August and September 2022. The samples underwent Cryptosporidium detection by nested PCR and small subunit (SSU) rRNA gene sequence analysis. Four Cryptosporidium species were identified, including C. parvum, C. bovis, C. ryanae, and C. andersoni, with an overall prevalence of 4.4% (40/909). Based on sequence analysis of the 60 kDa glycoprotein gene of C. parvum and C. bovis, three subtypes of C. parvum were identified, namely two previously known subtypes (IIdA19G1 and IIdA20G1), and one novel subtype (IIdA24G2). Two distinct subtype families were identified in C. bovis (XXVId and XXVIe). The high diversity of Cryptosporidium in dairy cattle and the emergence of a novel subtype of C. parvum in Heilongjiang Province suggest that dairy cattle may serve as a significant source of zoonotic cryptosporidiosis infection in this region.

Prevalence and Molecular Characterization of Bovine Parainfluenza Virus Type 3 in Cattle Herds in China

Bovine parainfluenza virus type 3 (BPIV3) is a common respiratory pathogen that causes respiratory illness in cattle and makes a major contribution to the bovine respiratory disease complex (BRDC); however, data on the prevalence and molecular features of BPIV3 are still scarce in China. To investigate the epidemiological characteristics of BPIV3 in China, between September 2020 and June 2022, 776 respiratory samples were received from 58 BRDC-affected farms located in 16 provinces and one municipality. Those were screened for BPIV3 using a reverse transcription insulated isothermal PCR (RT-iiPCR) assay. Meanwhile, the HN gene and complete genome sequence of strains from different provinces were amplified, sequenced, and analyzed. The tests showed that 18.17% (141/776) of samples tested were positive for BPIV3, which originated from 21 farms in 6 provinces. Moreover, 22 complete HN gene sequences and 9 nearly complete genome sequences were obtained from the positive samples. Phylogenetic analysis based on the HN gene and complete genome sequences revealed that the sequences were clustered in one large clade for all Chinese BPIV3 genotype C strains, while overseas strain sequences of BPIV3 genotype C clustered into other clades. Moving beyond the known complete genome sequences of BPIV3 in GenBank, a total of five unique amino acid mutations were found in N protein, F protein, and HN protein in Chinese BPIV3 genotype C strains. Taken together, this study reveals that BPIV3 genotype C strains, the dominant strains in China, have a broad geographical distribution and some unique genetic characteristics. These findings contribute to our understanding of the epidemiological characteristics and genetic evolution of BPIV3 in China.

First Isolation and Characteristics of Bovine Parainfluenza Virus Type 3 from Yaks

The yaks belong to the genus Bos within the family Bovidae that live in the Tibet Plateau and is an indispensable economic resource for the local herders. Respiratory tract infections are common diseases in yaks caused by various pathogens; however, there have been no reports of bovine parainfluenza virus type 3 (BPIV3) infection. This study was conducted to investigate the pathogens and analyze their characteristics from the four yak lung samples with severe respiratory tract infection symptoms in the yak farm. Results showed that out of four lung samples, three were identified as BPIV3-positive by RT-PCR. A BPIV3 strain (10^6.5 TCID₅₀/mL) was successfully isolated from the BPIV3-positive lung samples using Madin–Darby bovine kidney cells. The isolate caused systemic infection in the BALB/c mice and induced pathological changes in the lungs. Moreover, three complete BPIV3 genomes were amplified from the clinical samples. Phylogenetic trees based on the complete genomes, hemagglutinin-neuraminidase protein (HN), phosphoprotein (P), and large polymerase subunit protein (L) amino acid sequences showed that the complete BPIV3 genomes belonged to BPIV3 genotype C, and clustered into a large branch with the Chinese strains, although the three yak BPIV3 strains were clustered into a small branch. Compared to known BPIV3 genotype C strains in GenBank, the three genomes of yak BPIV3 showed four identical amino acid mutations in the HN, P and L proteins, suggesting a unique genetic evolution of BPIV3 in yaks. This study first isolated and characterized the BPIV3 from yaks, which contributed to the understanding of the infection and evolution of BPIV3 in yaks in the Tibet Plateau.

Emergence of zoonotic Cryptosporidium parvum in China

Zoonotic cryptosporidiosis is a major public health problem in industrialized nations; in those countries it is caused mainly by Cryptosporidium parvum IIa subtypes that are prevalent in dairy calves. Because of the short history of intensive animal farming in China, strains of C. parvum are found only on some dairy farms in this country and are the IId subtypes. However, the prevalence of C. parvum is increasing rapidly, with IIa subtypes recently detected in a few grazing animals, and both IIa and IId subtypes are emerging in humans. As animal farming intensifies, China may follow in the footsteps of industrialized nations where zoonotic cryptosporidiosis is rampant. One Health and biosecurity measures are urgently needed to slow down the dispersal of autochthonous IId subtypes and imported IIa subtypes.

Prevalence of Cryptosporidium spp. in Yaks (Bos grunniens) in China: A Systematic Review and Meta-Analysis

Cryptosporidium spp., the causative agent of cryptosporidiosis, can infect a variety of hosts. So far, there has been limited information regarding Cryptosporidium spp. infection in yaks (Bos grunniens). Here, we performed the first systematic review and meta-analysis for Cryptosporidium spp. infection in yaks in China. To perform the meta-analysis, five databases (Chinese National Knowledge Infrastructure (CNKI), VIP Chinese journal database, WanFang Data, PubMed, and ScienceDirect) were employed to search for studies related to the prevalence of Cryptosporidium spp. in yaks in China. The total number of samples was 8,212, and the pooled Cryptosporidium spp. prevalence in yaks was estimated to be 10.52% (1192/8012). The prevalence of Cryptosporidium spp. in yaks was 13.54% (1029/5277) and 4.49% (148/2132) in northwestern and southwestern China, respectively. In the sampling year subgroups, the prevalence before 2012 (19.79%; 650/2662) was significantly higher than that after 2012 (6.07%; 437/4476). The prevalence of Cryptosporidium spp. in cold seasons (20.55%; 188/794) was higher than that in warm seasons (4.83%; 41/1228). In the age subgroup, the yaks with age < 12 months had a higher prevalence (19.47%; 231/1761) than that in yaks with age ≥12 months (16.63%; 365/2268). Among 12 Cryptosporidium spp. species/genotypes, the C. bovis had the highest prevalence. Moreover, the effects of geography (latitude, longitude, precipitation, temperature, and altitude) and climate on Cryptosporidium spp. infection in yaks were evaluated. Through analyzing the risk factors correlated with the prevalence of Cryptosporidium spp., we recommend that effective management measures should be formulated according to the differences of different geographical factors, in order to prevent cryptosporidiosis and reduce economic losses in yaks in China.

FIRST REPORT OF GENUS Cryptosporidium IN CERVIDS SPECIES: Mazama americana, Mazama nana AND Blastocerus dichotomus

We analyzed Cryptosporidium spp. in fecal samples of wild cervids (Ozotoceros bezoarticus, Blastocerus dichotomus, Mazama nana, Mazama americana, and Mazama bororo) from many Brazilian regions, a fact unprecedented in the literature. Sniffer dogs were used to collect 936 fecal samples of cervids from 14 Brazilian localities. Cervids species were identified using polymerase chain reaction (PCR) performed from genomic DNA extracted from 563 fecal samples of Ozotoceros bezoarticus, Blastocerus dichotomus, Mazama nana, Mazama americana, and Mazama bororo. Cryptosporidium spp. oocyst screening was performed using malachite green negative staining. Nested PCR (nPCR) protocols targeting the 18S rRNA and GP60 genes followed by genetic sequencing were performed for Cryptosporidium spp. detection and Cryptosporidium parvum subtyping, respectively. Nested PCR targeting actin gene and genetic sequencing were performed in samples with non-identified Cryptosporidium species by 18S rRNA amplicon sequencing. The association between the occurrence of Cryptosporidium and the presence of bovines in the same locality was evaluated using Fisher's exact test. The positivity rates of diagnostic methods were compared by McNemar test and the Kappa correlation coefficient. The prevalence rates of Cryptosporidium spp. in cervids were 1.42% (8/563) and 0.36% (2/563) by nPCR and malachite green negative staining, respectively. C. parvum IIaA16G3R1 isolate was identified in three fecal samples from M. americana, two from M. nana and one from B. dichotomus. Cryptosporidium ryanae were found in one sample from B. dichotomus. We identified a new Cryptosporidium genotype, named Cryptosporidium deer genotype BR, from one M. americana fecal sample.

Occurrence of Cryptosporidium and Giardia in wild birds from Qinghai Lake on the Qinghai-Tibetan Plateau, China

Cryptosporidium and Giardia are important intestinal zoonotic pathogens that can infect various hosts and cause diarrhoeal diseases. There are few reports of the epidemiological prevalence and molecular characterization of Cryptosporidium and Giardia in wild birds around Qinghai Lake and in the surrounding areas on the Qinghai-Tibetan Plateau, Northwest China. Therefore, the aim of this study was to determine the Cryptosporidium spp. and Giardia duodenalis genotypes and their epidemiological prevalence in wild birds by PCR amplification. To our knowledge, this is the first report of a variety of Cryptosporidium spp. and G. duodenalis infections in wild birds from that area, with overall prevalence rates of 8.98% (61/679) and 3.39% (23/679), respectively. Furthermore, PCR sequencing confirmed the presence of Cryptosporidium baileyi (n = 3), Cryptosporidium parvum (n = 58), and G. duodenalis assemblage B (n = 19) and E (n = 4) in wild birds from the areas around Qinghai Lake. The results of the present study demonstrated the wide distribution of Cryptosporidium and Giardia among wild birds, which has potential public health significance. Moreover, the study findings also provided useful molecular epidemiological data for monitoring and investigating the two parasitic protozoa in wild animals and surrounding environments.

Development of a Quantitative Real-Time PCR Assay for Detection of Cryptosporidium spp. Infection and Threatening Caused by Cryptosporidium parvum Subtype IIdA19G1 in Diarrhea Calves from Northeastern China

Parasitic diarrheal disease is a major cause of morbidity and mortality in the developing world. Calves are highly susceptible to Cryptosporidium spp. infection that resulted in diarrhea, growth retardation, and weight loss, and was one of the most common enteropathogens. It is especially difficult for molecular detection of calves with inapparent or subclinical infections of cryptosporidiosis. In view of this, this study established a real-time quantitative PCR (RT-qPCR) detection method to clarify its epidemic characteristics, based on Cryptosporidium 18S rRNA gene with the 150 bp product length to investigate the infection of Cryptosporidium spp. in northeastern China The standard curve equation is Ct = -2.91 × lg (Cryptosporidium spp. copies) +10.18, with better sensitivity, stability, and reproducibility. A total of 148 out of 425 fecal samples (34.82%) were detected Cryptosporidium positive with RT-qPCR, including (36.11%) in Heilongjiang province (29.60%), (29.6%) in Jilin province, and (37.50%) in Liaoning province. The infection prevalence of Cryptosporidium parvum, Cryptosporidium ryanae, Cryptosporidium andersoni, and Cryptosporidium bovis from calves in order from high to low was 14.35% (95% confidence interval [CI], 11.2-18.1), 6.12 (95% CI, 4.0-8.8), 2.35 (95% CI, 1.1-4.3), and 0.47 (95% CI, 0.1-1.7), respectively, suggesting C. parvum was the predominant species in calves in northeastern China. Using 60-kDa glycoprotein gp60 gene, all of the 61 C. parvum-positive specimens were further precisely confirmed to IIdA19G1 subtype. This suggested that IIdA19G1 subtype of C. parvum could threaten to cause diarrhea calves from notheastern China (p < 0.01). The prevalence of 34.82% (148/425) using RT-qPCR had a significant difference compared with the prevalence of nested-PCR (23.29%) and microscopic examination (3.76%). The findings improved the epidemiological knowledge of calves infected with cryptosporidiosis in China, highlighting the importance of ongoing Cryptosporidium surveillance.

Cryptosporidium parvum in brown brocket (Mazama gouazoubira) from Brazil: First report of the subtype IIaA16G3R1 in cervids

This research had as objective to evaluate the occurrence and to characterize genetically the infections by Cryptosporidium in Mazama gouazoubira. By a non-invasive harvest methodology using trained sniffer dogs to locate fecal samples of cervids, 642 fecal samples were obtained from six Brazilian localities. The cervids species responsible for the excretion of each fecal sample were identified by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), using the mitochondrial cytochrome b target gene (cyst b) and the restriction enzymes Sspl, AflIII and BstN. From this identification, 437 fecal samples of M. gouazoubira were selected for research of Cryptosporidium spp. performed through negative staining with malachite green and polymerase chain reaction (nPCR), with the subunit of 18S rRNA gene, followed by sequencing the amplified products. In the samples that were diagnosed the presence of parasite species with zoonotic potential, genotyping was also performed using nPCR with the subunit of GP60 gene. Statistical analysis consisted of the Fisher exact test to verify the association of the presence of the enteroparasite in relation to the presence of cattle in each locality, and the McNemar tests and Kappa correlation coefficient used to compare the results obtained between the two diagnostic techniques. In the fecal samples of M. gouazoubira the occurrences of Cryptosporidium were diagnosed in 1.6% (7/437) and 1.1% (5/437), respectively, through nPCR and microscopy. Cryptosporidium. parvum was diagnosed in 100% (7/7) of the samples submitted to sequencing (18S gene). The IIaA16G3R1 subtype was diagnosed in five of the C. parvum samples submitted to genotyping (GP60 gene). This is the first world report of C. parvum in M. gouazoubira and subtype IIaA16G3R1 in cervids.

Dairy Calves in Uruguay Are Reservoirs of Zoonotic Subtypes of Cryptosporidium parvum and Pose a Potential Risk of Surface Water Contamination

Cryptosporidium parvum, a major cause of diarrhea in calves, is of concern given its zoonotic potential. Numerous outbreaks of human cryptosporidiosis caused by C. parvum genetic subtypes are reported yearly worldwide, with livestock or water being frequently identified sources of infection. Although cryptosporidiosis has been reported from human patients in Uruguay, particularly children, epidemiologic information is scant and the role of cattle as reservoirs of zoonotic subtypes of C. parvum has not been explored. In this study, we aimed to (a)-identify C. parvum subtypes infecting dairy calves in Uruguay (including potentially zoonotic subtypes), (b)-assess their association with calf diarrhea, (c)-evaluate their spatial clustering, and (d)-assess the distance of infected calves to surface watercourses draining the farmlands and determine whether these watercourses flow into public water treatment plants. Feces of 255 calves that had tested positive for Cryptosporidium spp. by antigen ELISA were selected. Samples had been collected from 29 dairy farms in seven Uruguayan departments where dairy farming is concentrated and represented 170 diarrheic and 85 non-diarrheic calves. Selected samples were processed by nested PCRs targeting the 18S rRNA and gp60 genes followed by sequencing to identify C. parvum subtypes. Of seven C. parvum subtypes detected in 166 calves, five (identified in 143 calves on 28/29 farms) had been identified in humans elsewhere and have zoonotic potential. Subtype IIaA15G2R1 was the most frequent (53.6%; 89/166), followed by IIaA20G1R1 (24.1%; 40/166), IIaA22G1R1 (11.4%; 19/166), IIaA23G1R1 (3.6%; 6/166), IIaA17G2R1 (3%; 5/166), IIaA21G1R1 (2.4%; 4/166), and IIaA16G1R1 (1.8%; 3/166). There were no significant differences in the proportions of diarrheic and non-diarrheic calves infected with any of the C. parvum subtypes. Two spatial clusters were detected, one of which overlapped with Uruguay's capital city and its main water treatment plant (Aguas Corrientes), harvesting surface water to supply ~1,700,000 people. Infected calves on all farms were within 20–900 m of a natural surface watercourse draining the farmland, 10 of which flowed into six water treatment plants located 9–108 km downstream. Four watercourses flowed downstream into Aguas Corrientes. Calves are reservoirs of zoonotic C. parvum subtypes in Uruguay and pose a public health risk.

Antimicrobial Resistance, Virulence Genes, and Biofilm Formation Capacity Among Enterococcus species From Yaks in Aba Tibetan Autonomous Prefecture, China

Yaks provide necessities such as meat and milk for Tibetans living at high altitudes on and around the Qinghai-Tibetan Plateau. Enterococci are ubiquitous members of the animal gut microbiota that can cause biofilm-associated opportunistic infections. Meanwhile, multidrug-resistant Enterococcus also poses a serious threat to public health. This study aims to characterize antibiotic resistance, virulence genes, and biofilm formation of enterococci from yaks. From April 2018 to July 2019, we collected 395 fecal samples of yaks in Aba Tibetan Autonomous Prefecture, China. Enterococci isolated from the samples were identified and classified according to the 16S rDNA sequence. The antibiotic resistance of each isolate was detected according to the Kirby-Bauer disk diffusion method, and antibiotic resistance genes were detected by polymerase chain reaction (PCR) and sequencing. Enterococcal biofilms were assessed using standard procedures. Different virulence genes were detected by PCR and sequencing. In total, 381 enterococci strains were recovered, with Enterococcus faecalis (41.99%) and Enterococcus faecium (37.80%) being the predominant species. Many isolates were multidrug- resistant (60.37%) and showed a high resistance rate to rifampicin (64.30%) and tetracycline (61.54%). We also detected various antimicrobial resistance (AMR) genes in the tested strains. The E. faecalis strains had higher frequency of biofilm formation and virulence genes than other enterococcal species. This is the first report that shows yaks are repositories for drug-resistant enterococci with virulent determinants and biofilms that may spread into humans and to environment. This study also provides useful data suggesting that enterococci may pose a potential health risk to yaks. Therefore, active surveillance of AMR and pathogenesis in enterococci from yaks is urgently warranted.

Prevalence and genotyping of bovine Cryptosporidium species in the Mediterranean and Central Anatolia Region of Turkey

The prevalence of Cryptosporidium species in calves and heifers with relation to diarrhea from several herds was investigated in this study. Fecal samples were collected from 135 and 120 pre-weaned calves and 79 and 130 heifers raised in the Central Anatolia (CAR) and Mediterranean Regions (MR) of Turkey, respectively. A total of 86 post-weaned calves in CAR were also included in the study. For diagnostic comparison, all samples were examined by microscopic examination, SSU rRNA nested PCR and TaqMan real-time PCR for the presence of oocyst and Cryptosporidium DNA. In total, 102 (34.0 %) and 93 (37.2 %) of the examined samples from CAR and MR were found positive for Cryptosporidium DNA with both nested PCR and real-time PCR analyses, respectively with an overall prevalence of 35.5 %. The diagnostic sensitivity and specificity of microscopic examination were determined as 68.7 % and 100.0 % compared to molecular tools, respectively. RFLP and sequence analyses of the SSU rRNA from the PCR products revealed that 138 (70.8 %) out of 195 positive isolates were C. parvum further confirming the species-specific real-time PCR results. Among the remaining 57 (29.2 %) positive isolates, 30 (15.4 %) and 27 (13.8 %) were characterized as C. ryanae and C. bovis, respectively. C. parvum was the dominant species in pre-weaned calves especially with diarrhea while C. bovis and C. ryanae were mostly found in post-weaned calves and heifers. The sequence analyses of the gp60 gene of C. parvum isolates revealed two subtypes (IIaA13G2R1, IIaA14G1R1) belonging to zoonotic family IIa, with IIaA13G2R1 being the most common in diarrheic calves.

Molecular characterization and distribution of Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi from yaks in Tibet, China

BACKGROUND

With worldwide distribution and importance for veterinary medicine, Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi have been found in a wide variety of vertebrate hosts. At present, few available molecular data can be used to understand the features of genetic diversity of these pathogens in areas without or less intensive farming. Dominated by grazing, Tibet is a separate geographic unit in China and yaks are in frequent contact with local herdsmen and necessary for their daily life. Therefore, to investigate the distribution of these pathogens in yaks of Tibet, 577 fecal specimens were screened using nested PCR for the presence and genotypes of the three intestinal pathogens.

RESULTS

The overall prevalence of Cryptosporidium spp., G. duodenalis, and E. bieneusi were 1.4% (8/577), 1.7% (10/577), and 5.0% (29/577), respectively. Cryptosporidium andersoni (n = 7) and Cryptosporidium bovis (n = 1) were detected by sequence analysis of the SSU rRNA gene. Genotyping at the SSU rRNA and triosephosphate isomerase genes suggested that all G. duodenalis positive specimens belonged to assemblage E. Sequence analysis of the internal transcribed spacer gene identified six known E. bieneusi genotypes: BEB4 (n = 11), I (n = 6), D (n = 5), J (n = 2), CHC8 (n = 1), and BEB6 (n = 1). One subtype (A5,A4,A2,A1) for C. andersoni and three multilocus genotypes for E. bieneusi were identified by multilocus sequence typing.

CONCLUSIONS

We report for the first time the status of three enteric pathogens infection simultaneously for grazing yaks in Tibet. Yaks in our study are likely to impose a low zoonotic risk for humans. The molecular epidemiology data add to our knowledge of the characteristics of distribution and transmission for these pathogens in Tibet and their zoonotic potential and public health significance.

Prevalence of gastrointestinal parasites in free-range yaks (Bos grunniens) in Gansu Province, Northwest China

BACKGROUND

Little information about the prevalence of gastrointestinal parasites in yaks (Bos grunniens) in northwest China is available. Therefore, the objective of the study was to quantify faecal egg counts of gastrointestinal parasites (helminths and coccidia) in free-range yaks from Gannan Tibetan Autonomous Prefecture, Gansu Province, Northwest China.

RESULTS

Parasites were detected in 290 of 733 (39.56%) faecal samples. The results showed that Strongylidae, Trichuris spp. and Eimeria spp. were detected all year round, Strongyloides papillosus was detected in autumn and summer, and Nematodirus spp. was detected in both autumn and spring. In contrast, Fasciola spp. was only detected in spring. The prevalence rates of parasitic infections in different seasons were significantly different.

CONCLUSIONS

To our knowledge, this is the first investigation of gastrointestinal parasites in yaks (Bos grunniens) in Gansu, China. The results demonstrated a high prevalence of gastrointestinal parasitic infections, specifically GN infections, in yaks in GTAP and these infections can cause economic losses to the local cattle industry.

First detection of neboviruses in yak (Bos grunniens) and identification of a novel neboviruses based on complete genome

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This is the first detection of neboviruses in yak (Bos grunniens).

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Neboviruses has been widely circulated among yak in Qinghai-Tibet Plateau, China.

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A novel neboviruses was identified, and it has spread in local region.

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New insights about the prevalence and evolution of neboviruses.

Neboviruses (NeVs) is an important causative agent of calf diarrhea. Here, 354 diarrhoeic samples were collected from yak on 55 farms in the Qinghai-Tibet Plateau, China. 22.0% of the diarrhoeic samples were detected as NeVs-positive by RT–PCR assay. Phylogenetic analysis of 78 NeVs RdRp fragments showed that 69 strains were closely related to NB-like strains, and the remaining 9 strains were clustered into an independent branch, which may represent a novel RdRp genotype. Two complete NeVs genomes (YAK/NRG-17/17/CH and YAK/HY1-2/18/CH) were successfully sequenced with 7459 nt and 7460 nt in length, respectively. The genomes of the two strains only shared 68.1%–69.3% nt identity with all six known NeVs genomes, and phylogenetic trees based on its genome, VP1, RdRp, VP2, P34, NTPase, P30, VPg and 3CLpro proteins suggested that the two strains may represent a novel NeVs strain with novel VP1 genotype and novel RdRp genotype. Notably, 11.5% NeVs strains were screened as the novel NeVs strains based VP1 and RdRp sequences. These novel NeVs strains were detected from 6 farms in two counties, indicating that the novel NeVs has spread in local region. To best of our knowledge, this is the first detection of NeVs in yak. Moreover, a novel NeVs strain was identified based on complete genome. These results contribute to further understand the prevalence and genetic evolution of NeVs.

Molecular characterization of Giardia intestinalis and Cryptosporidium parvum from calves with diarrhoea in Austria and evaluation of point-of-care tests

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Giardia intestinalis (48/177) and Cryptosporidium parvum (98/177) occur in Austrian calves.

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C. parvum genotypes IIaA15G2R1, IIaA19G2R2, IIaA21G2R1 and IIaA14G1R1 were found.

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Giardia intestinalis assemblage E and a single sample of assemblage A were found.

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Cryptosporidium was detected mostly in the first two weeks of age (72/102).

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Point-of-care test validity varied greatly for Giardia and Cryptosporidium.

To obtain information about the occurrence and genotype distribution of G. intestinalis and C. parvum in Austrian cattle, faecal samples from diarrhoeic calves younger than 180 days of age originating from 70 farms were examined. Of the 177 faecal samples, 27.1% were positive for Giardia cysts (immunofluorescence microscopy) and 55.4% for Cryptosporidium oocysts (phase-contrast microscopy). Positive samples were characterized by nested PCR for Giardia, 83.3% (triosephosphate isomerase; tpi) and 89.6% (β-giardin; bg) were positive, while the Cryptosporidium nested PCR returned 92.5% (60-kDa glycoprotein) positive results. Sequence analysis revealed one assemblage A-positive sample and 30 (bg) respectively 29 (tpi) assemblage E-positive samples for G. intestinalis. For C. parvum four subtypes within the IIa family (IIaA15G2R1, n = 29; IIaA19G2R2, n = 3; IIaA21G2R1, n = 2; IIaA14G1R1, n = 1) could be differentiated. Validation of two immunochromatographic point-of-care tests resulted in a sensitivity of 29.2% and 77.6%; a specificity of 98.4% and 91.1% for the detection of Giardia intestinalis and Cryptosporidium parvum, respectively. Results confirm the widespread occurrence of both protozoa in diarrhoeic calves in Austria.

Detection of Cryptosporidium and Giardia in the slaughterhouse, sewage and river waters of the Qinghai Tibetan plateau area (QTPA), China

The occurrence of Cryptosporidium and Giardia species in slaughter, sewage and river waters of the Qinghai Tibetan Plateau Area (QTPA), China, was investigated. A total of 456 samples were collected from different locations in the QTPA to study the contamination rates of Cryptosporidium spp. and Giardia via PCR and subsequent sequence analysis. Ten samples were Cryptosporidium positive, and 97 were Giardia positive, as confirmed by PCR amplification of the SSU rRNA gene. The percentages of positive Cryptosporidium and Giardia detection were 2.2% (10/456) and 21.3% (97/456), respectively. Cryptosporidium was detected in only sewage and river waters. Six species of Cryptosporidium were identified: Cryptosporidium hominis (n = 5), C. andersoni (n = 1), C. environmental (n = 1), C. struthionis (n = 1), C. canis (n = 1), and C. parvum (n = 1). G. duodenalis assemblage A was identified in almost all positive samples (n = 96), and one sample harboured G. duodenalis assemblage E. The results suggest that Cryptosporidium and Giardia species circulate through the aqueous environment and different hosts. Therefore, we strongly recommend that the local government and health authorities in China undertake control measures to reduce the contamination of water sources by these protozoa to protect the health of humans and animals.

An apple a day: an outbreak of cryptosporidiosis in Norway associated with self-pressed apple juice

In the autumn of 2018, an outbreak of cryptosporidiosis affected adult employees from the same company in Western Norway. The organism was Cryptosporidium parvum, GP60 subtype IIaA14G1R1. All those infected had drunk from the same container of self-pressed apple juice. Incubation period (1 week) and clinical signs were similar among those infected, although some experienced a more prolonged duration of symptoms (up to 2-3 weeks) than others. The infections resulted after consumption from only one of 40 containers of juice and not from any of the other containers. It seems that although Cryptosporidium oocysts were detected in a sample from another container, the contamination did not affect the whole batch. This is perhaps indicative of a restricted contamination event, either from contaminated ground in the orchard, or during collection of the fruit, or during processing. Although outbreaks of food-borne cryptosporidiosis have previously been associated with consumption of contaminated apple juice, most of the more recent outbreaks of food-borne cryptosporidiosis have been associated with salad vegetables or herbs. This outbreak, the first outside USA reported to be associated with apple juice, is a timely reminder that such juice is a suitable transmission vehicle for Cryptosporidium oocysts, and that appropriate hygienic measures are essential in the production of such juice, including artisanal (non-commercial) production.

Socio-economic burden of parasitic infections in yaks from 1984 to 2017 on Qinghai Tibetan Plateau of China-A review

Yak is an important animal for the Tibetans at Qinghai-Tibetan Plateau of China. The burden of parasitic diseases has been a major threat to the health of yaks at this region presenting a considerable socio-economic losses and impact to yak production and local nomads. Keeping in view, we collected the published papers from 1984 to 2017 on major parasitic infections in yaks by electronic literature search from five databases including CNKI, Google, PubMed, Science Direct and Web of Science. The prevalence of Eimeria, Babesia, Theileria, Hypodermosis, Cystic echinococcosis, Alveolar echinococcosis, Toxoplasma gondii, Neospora caninum, Cryptosporidium, Giardia duodenalis, Enterocytozoon bieneusi, Toxocara vitulorum, and Fascioliasis infection in yaks was found to be 48.02%, 13.06%, 36.11%, 59.85%, 16.93%, 0.99%, 20.50%, 5.14%, 10.00%, 3.68%, 4.07%, 22.23% and 28.7% respectively. Data presented are contemplated to enhance our current understanding on the major parasitic diseases of yaks at Qinghai Tibetan plateau, China. The main aim of this effort is to ameliorate the effects of the parasitic burden in this specie; so that, the attempts are made to minimize the incidence of these infections in future to raise the socio-economic levels of local community.

Expression Profiles of mRNA and lncRNA in HCT-8 Cells Infected With Cryptosporidium parvum IId Subtype

Cryptosporidium parvum is one of the most important enteric protozoan pathogens, responsible for severe diarrhea in immunocompromised human and livestock. However, few effective agents were available for controlling this parasite. Accumulating evidences suggest that long non-coding RNA (lncRNA) played key roles in many diseases through regulating the gene expression. Here, the expression profiles of lncRNAs and mRNAs were analyzed in HCT-8 cells infected with C. parvum IId subtype using microarray assay. A total of 821 lncRNAs and 1,349 mRNAs were differentially expressed in infected cells at 24 h post infection (pi). Of them, all five types of lncRNAs were identified, including 22 sense, 280 antisense, 312 intergenic, 44 divergent, 33 intronic lncRNAs, and 130 lncRNAs that were not found the relationship with mRNAs’ location. Additionally, real-time polymerase chain reactions of 10 lncRNAs and 10 mRNAs randomly selected were successfully confirmed the microarray results. The co-expression and target prediction analysis indicated that 27 mRNAs were cis-regulated by 29 lncRNAs and 109 were trans-regulated by 114 lncRNAs. These predicted targets were enriched in several pathways involved in the interaction between host and C. parvum, e.g., hedgehog signaling pathway, Wnt signaling pathway, and tight junction, suggesting that these differentially expressed lncRNAs would play important regulating roles during the infection of C. parvum IId subtype.

Prevalence and molecular characterization of Cryptosporidium spp. and Giardia duodenalis in 1-2-month-old highland yaks in Qinghai Province, China

Cryptosporidium and Giardia are ubiquitous parasites that infect humans and animals. Few reports are available on the prevalence of these two protozoan parasites in yaks (Bos grunniens). In this study, 344 faecal samples were collected from yaks with diarrhoea in the Chenduo and Nangqian counties of Qinghai Province, China. Cryptosporidium spp. and Giardia duodenalis were detected by light and immunofluorescence microscopy and nested PCR (nPCR). Fifteen samples were positive (4.5%) by Kinyoun staining, 40 (11.6%) samples were positive by immunofluorescence test (IFT), and 39 (11.3%) samples were positive by nPCR for Cryptosporidium spp., Cryptosporidium bovis (11/39, 28.2%) was the most prevalent species, followed by C. ryanae (6/39, 15.4%), C. andersoni (5/39, 12.8%), C. struthionis (5/39, 12.8%), C. parvum (5/39, 12.8%), C. hominis (4/39, 10.3%) and C. canis (3/39, 7.7%). Thirteen out of 344 (3.8%) samples were positive for Giardia by simple microscopy, 20 (5.8%) by IFT and 18 samples (5.2%) yak faecal samples were Giardia positive by nPCR. Two G. duodenalis assemblages (B, E) were detected in this study. Nine positive samples for G. duodenalis assemblage E were from the towns of Xiewu (8/9, 4.9%) and Xiangda (1/9, 1.3%), and nine positive samples (9/9, 8.5%) for G. duodenalis assemblage B were from the town of Zhenqin. This report provides information about infection with Cryptosporidium species and G. duodenalis assemblages in domesticated 1-2-month-old highland yaks living in the Qinghai-Tibet Plateau region of China.

The first report of Cryptosporidium spp. in Microtus fuscus (Qinghai vole) and Ochotona curzoniae (wild plateau pika) in the Qinghai-Tibetan Plateau area, China

Cryptosporidium is one of the most important genera of intestinal zoonotic pathogens, which can infect various hosts and cause diarrhoea. There is little available information about the molecular characterisation and epidemiological prevalence of Cryptosporidium spp. in Microtus fuscus (Qinghai vole) and Ochotona curzoniae (wild plateau pika) in the Qinghai-Tibetan Plateau area of Qinghai Province, Northwest China. Therefore, the aim of this study was to determine Cryptosporidium species/genotypes and epidemiological prevalence in these mammals by detecting the SSU rRNA gene by PCR amplification. The Cryptosporidium spp. infection rate was 8.9% (8/90) in Qinghai voles and 6.25% (4/64) in wild plateau pikas. Positive samples were successfully sequenced, and the following Cryptosporidium species were found: C. parvum, C. ubiquitum, C. canis and a novel genotype in Qinghai voles and C. parvum and a novel genotype in wild plateau pikas. This is the first report of Cryptosporidium infections in M. fuscus and wild O. curzoniae in Northwest China. The results suggest the possibility of Cryptosporidium species transmission among these two hosts, the environment, other animals and humans and provide useful molecular epidemiological data for the prevention and control of Cryptosporidium infections in wild animals and the surrounding environments. The results of the present study indicate the existence of Cryptosporidium species infections that have potential public health significance. This is the first report of Cryptosporidium multi-species infections in these animal hosts.

Cryptosporidium-associated diarrhoea in neonatal calves in Algeria

Neonatal calf diarrhoea triggered by the enteric protozoan parasite Cryptosporidium is a leading cause of morbidity and mortality in calves aged 1-month-old or younger globally. Infected cattle in general and calves in particular have also been demonstrated as major contributors of zoonotic C. parvum oocysts in the environment and have been linked to a number of waterborne outbreaks of human cryptosporidiosis. Little is known on the occurrence, geographical distribution, and molecular diversity of Cryptosporidium infections affecting bovine populations in Algeria. In this study faecal specimens were randomly collected from 460 cattle aged between two days and 18 months on 10 farms located in the provinces of Aïn Defla, Blida, Sétif, and Tizi Ouzou between the autumn of 2015 and the spring of 2016. Faecal samples were microscopically examined using the modified Ziehl-Neelsen acid-fast technique as screening method. Microscopy-positive samples were confirmed by a commercial coproantigen enzyme-linked immunosorbent assay (Bio-X Diagnostics). The identification of Cryptosporidium species and sub-genotypes in confirmed samples was conducted by PCR and sequence analyses of the small subunit ribosomal RNA (ssu rRNA) and the 60 kDa glycoprotein (gp60) genes of the parasite. Overall, 52.2% (240/460) of the investigated cattle tested positive to Cryptosporidium by microscopy. The infection was widespread in all 10 farms surveyed, but was significantly more prevalent in those from Blida in the central part of the country. Bovine cryptosporidiosis affected cattle of all age groups but with different outcomes. Pre-weaned (up to one month old) calves typically presented with diarrhoea, whereas older animals mostly harboured sub-clinical infections. The commercial ELISA used only detected 15.8% (38/240) of the samples that previously tested positive by microscopy, demonstrating a poor performance in field epidemiological surveys. Sequence analysis of the 29 isolates generated at the ssu rRNA loci confirmed the presence of four Cryptosporidium species including C. parvum (72.4%), C. bovis (13.8%), C. andersoni, (3.4%), and C. ryanae (3.4%). Two additional isolates (7.0%) could only be identified at the genus level. Eight out of the 21 isolates assigned to C. parvum were identified as sub-genotype IIaA16G2R1 at the gp60 locus. C. parvum was almost exclusively found infecting pre-weaned calves, whereas C. ryanae and C. andersoni were only detected in asymptomatic animals. Bovine cryptosporidiosis is highly endemic in the surveyed area and represents a veterinary public health concern that should be adequately tackled by Algerian veterinary health authorities and policy makers.

Molecular detection and prevalence of Cryptosporidium spp. infections in two types of domestic farm animals in the Qinghai-Tibetan Plateau Area (QTPA) in China

The objective of this study was to determine the prevalence of Cryptosporidium species infections in young cattle and sheep in the north-eastern part of the Qinghai-Tibetan Plateau Area (QTPA), north-western China. A total number of 454 faecal samples (389 from cattle and 65 from sheep) were collected and investigated to determine the prevalence of Cryptosporidium spp. oocysts. Cryptosporidium spp. infections detected in cattle (n = 56 positive samples) and sheep (n = 4 positive samples) were as following: C. andersoni (16/56, 28.6%) was the dominant species, followed by C. canis (9/56, 16.1%), C. bovis (9/56, 16.1%), C. hominis (8/56, 14.3%), C. struthionis (7/56, 12.5%), C. ryanae (5/56, 8.9%), and C. serpentis (2/56, 3.6%). Two Cryptosporidium species were detected in sheep: C. parvum (2/4) and C. canis (2/4). There were no mixed infections. C. hominis, C. struthionis, and C. serpentis are reported in domestic animals for the first time at the QTPA of China and our results indicate an anthropozoonotic transmission of C. hominis. The identification of Cryptosporidium spp. in domestic animals warrants better care of the farm animals in order to avoid contamination in vulnerable animal and human populations.

Advances and Perspectives on the Epidemiology of Bovine Cryptosporidium in China in the Past 30 Years

Major progress has been made in understanding the epidemiology of bovine Cryptosporidium in China in the past 30 years. The overall infection rate in that period was 14.50% (5265/36316), with different prevalence being observed among dairy cattle, yaks, beef cattle, and buffalo. The infection rate declined as the animals' ages increased and the lowest prevalence occurred in winter. Ten Cryptosporidium species and two genotypes have been found in cattle, with Cryptosporidium parvum, C. andersoni, C. bovis, and C. ryanae being the commonest species. Cryptosporidium bovis rather than C. parvum predominated in preweaned dairy cattle, and C. parvum IIdA15G1 and IIdA19G1 were the only subtypes detected in dairy cattle. Two subtype families, IIa and IId, were found in yaks. Population genetic analysis detected an epidemic population structure in C. andersoni, which suggested that the prevalence of C. andersoni in China is not attributable to the introduction of dairy cattle. Moreover, C. parvum IId subtypes probably dispersed from western Asia to other geographic regions based on population genetic analysis of isolates from China, Sweden, and Egypt. Therefore, we hypothesize that Cryptosporidium was introduced into China in the past, and different populations formed progressively in various hosts in response to diverse factors, including the transmission dynamics, geographic isolation, host specificity, and large-scale farming. More epidemiological studies are required to test this hypothesis and to clarify the prevalence and transmission of Cryptosporidium species in China.

Molecular Epidemiology of Cryptosporidiosis in China

Molecular epidemiology of cryptosporidiosis is an active research area in China. The use of genotyping and subtyping tools in prevalence studies has led to the identification of unique characteristics of Cryptosporidium infections in humans and animals. Human cryptosporidiosis in China is exemplified by the high diversity of Cryptosporidium spp. at species and subtype levels, with dominant C. hominis and C. parvum subtypes being rarely detected in other countries. Similarly, preweaned dairy calves, lambs, and goat kids are mostly infected with non-pathogenic Cryptosporidium species (C. bovis in calves and C. xiaoi in lambs and goat kids), with C. parvum starting to appear in dairy calves as a consequence of concentrated animal feeding operations. The latter Cryptosporidium species is dominated by IId subtypes, with IIa subtypes largely absent from the country. Unlike elsewhere, rodents in China appear to be commonly infected with C. parvum IId subtypes, with identical subtypes being found in these animals, calves, other livestock, and humans. In addition to cattle, pigs and chickens appear to be significant contributors to Cryptosporidium contamination in drinking water sources, as reflected by the frequent detection of C. suis, C. baileyi, and C. meleagridis in water samples. Chinese scientists have also made significant contributions to the development of new molecular epidemiological tools for Cryptosporidium spp. and improvements in our understanding of the mechanism involved in the emergence of hyper-transmissible and virulent C. hominis and C. parvum subtypes. Despite this progress, coordinated research efforts should be made to address changes in Cryptosporidium transmission because of rapid economic development in China and to prevent the introduction and spread of virulent and zoonotic Cryptosporidium species and subtypes in farm animals.

Epidemiology of Cryptosporidium infection in cattle in China: a review

The present review discusses the findings of cryptosporidiosis research conducted in cattle in China and highlights the currently available information on Cryptosporidium epidemiology, genetic diversity, and distribution in China, which is critical to understanding the economic and public health importance of cryptosporidiosis transmission in cattle. To date, 10 Cryptosporidium species have been detected in cattle in China, with an overall infection rate of 11.9%. The highest rate of infection (19.5%) was observed in preweaned calves, followed by that in juveniles (10.69%), postweaned juveniles (9.0%), and adult cattle (4.94%). The dominant species were C. parvum in preweaned calves and C. andersoni in postweaned, juvenile, and adult cattle. Zoonotic Cryptosporidium species (C. parvum and C. hominis) were found in cattle, indicating the possibility of transmission between humans and cattle. Different cattle breeds had significant differences in the prevalence rate and species of Cryptosporidium. This review demonstrates an age-associated, breed-associated, and geographic-related occurrence of Cryptosporidium and provides references for further understanding of the epidemiological characteristics, and for preventing and controlling the disease.

A novel astrovirus species in the gut of yaks with diarrhoea in the Qinghai–Tibetan Plateau, 2013

The yak (Bos grunniens) is an iconic symbol in the high-altitude region of the Qinghai–Tibetan Plateau. Diarrhoea is a common disease in yaks, resulting in major economic losses. To investigate the diversity of viral species, we reported the metagenomics-derived virome in a pooled faecal sample of 20 diarrhoeic yaks. The nine viruses found in the pooled diarrhoeic samples, in order of abundance of nucleic acid sequence, were influenza A virus, bovine viral diarrhoea virus (BVDV), rotavirus, ungulate tetraparvovirus 1 (bovine hokovirus), astrovirus (AstV), bovine enterovirus, hepatitis E virus, kobuvirus and woodchuck hepatitis virus. Compared with healthy yaks, only AstV had a significantly higher prevalence rate in diarrhoeal samples, indicating a correlation with the clinical symptoms of diarrhoea in yaks. To further investigate the molecular characterization of yak AstV, a near-full genome was obtained from a diarrhoeic sample. It was 6243 bp in length and shared 46.4–66.2 % similarity with other related bovine AstVs from faeces. Phylogenetic analysis of the genome demonstrated that the yak AstV fell within the bovine AstVs cluster, but was located in a unique lineage, suggesting a novel AstV species was identified in yaks. Interestingly, the ORF2 region of yak AstV had closer similarity and genetically relationship with deer AstV strain CcAstV-2 than that of the bovine AstVs. Further analysis showed that one possible interspecies recombination event occurred in ORF2. In summary, this study expanded our understanding of the viral communities of diarrhoeal yaks and identified a novel AstV that was associated with diarrhoea in yaks.

Public health significance of zoonotic Cryptosporidium species in wildlife: Critical insights into better drinking water management

Cryptosporidium is an enteric parasite that is transmitted via the faecal-oral route, water and food. Humans, wildlife and domestic livestock all potentially contribute Cryptosporidium to surface waters. Human encroachment into natural ecosystems has led to an increase in interactions between humans, domestic animals and wildlife populations. Increasing numbers of zoonotic diseases and spill over/back of zoonotic pathogens is a consequence of this anthropogenic disturbance. Drinking water catchments and water reservoir areas have been at the front line of this conflict as they can be easily contaminated by zoonotic waterborne pathogens. Therefore, the epidemiology of zoonotic species of Cryptosporidium in free-ranging and captive wildlife is of increasing importance. This review focuses on zoonotic Cryptosporidium species reported in global wildlife populations to date, and highlights their significance for public health and the water industry.

Distribution of Cryptosporidium species in Tibetan sheep and yaks in Qinghai, China

Few data are available on the distribution of Cryptosporidium species in Tibetan sheep and yaks, which are free-range animals living in a cold, low oxygen, and high ultraviolet radiation habitat. In this study, 904 fecal specimens were collected from 350 Tibetan sheep and 554 yaks in six counties. Cryptosporidium spp. were detected and differentiated by PCR and sequence analyses. Altogether, 43 (12.3%) Tibetan sheep and 158 (28.5%) yaks were positive for Cryptosporidium spp. In Tibetan sheep, Cryptosporidium xiaoi (39/43, 90.7%) was the dominant species, with the remaining cases (4/43, 9.3%) by Cryptosporidium ubiquitum. All C. ubiquitum specimens belonged to the subtype family XIIa. In contrast, Cryptosporidium andersoni (72/158, 45.6%), Cryptosporidium bovis (47/158, 29.7%), Cryptosporidium ryanae cattle type (35/158, 22.2%), C. ryanae buffalo type (2/158, 1.3%), and Cryptosporidium suis-like (2/158, 1.3%) were identified in yaks. Contradictory to previous observations, C. andersoni was one of the dominant Cryptosporidium species in yaks in this study. Despite sharing habitats, Tibetan sheep and yaks are evidently infected with different Cryptosporidium species.

Occurrence and molecular identification of Cryptosporidium spp. in dairy calves in Xinjiang, Northwestern China

A total of 514 fecal samples were collected from dairy calves on 15 farms in the Xinjiang Uyghur Autonomous Region in Northwestern China and were screened for Cryptosporidium spp. by PCR. The overall prevalence of Cryptosporidium was 16.0% (82/514), and the infection rate was 15.6% (37/237) and 16.2% (45/277) in pre- and post-weaned calves, respectively. PCR-restriction fragment length polymorphism (RFLP) and DNA sequence analyses of 82 positive fecal samples revealed the presence of four Cryptosporidium species; of these, 22 were Cryptosporidium parvum, 20 were Corynebacterium bovis, 9 were Cryptosporidium ryanae, 25 were Cryptosporidium andersoni, 2 were mixed C. bovis/C. parvum, and 4 were mixed C. bovis/C. ryanae infections. In pre-weaned calves, C. parvum was the most common species (22/37, 59.5%). In contrast, C. andersoni was the dominant species (23/45, 51.1%) in post-weaned calves. Subtyping analysis based on the 60-kDa glycoprotein (gp60) gene successfully identified 15 C. parvum isolates as being in the IId family; 11 were IIdA15G1 and 4 were IIdA14G1. Recent findings describing the C. parvum IId subtypes as the dominant group in humans and animals in China indicate that dairy calves may be an important source of zoonotic Cryptosporidium in China.

Prevalence and molecular characterization of Cryptosporidium spp. in dairy cattle, northwest China

Cryptosporidium spp. cause enteric diseases in a wide range of animals, including dairy cattle. However, limited information is available regarding prevalence and molecular characterization of Cryptosporidium spp. in dairy cattle in Gansu province and Ningxia Hui Autonomous Region (NXHAR), northwest China. A total of 2945 dairy feces samples (1257 from Gansu province and 1688 from NXHAR) were collected between December 2012 and March 2014 and were tested by PCR amplification of the small subunit (SSU) rRNA gene. A total of 150 (5.09 %, 58 from Gansu and 92 from NXHAR) samples were PCR-positive for Cryptosporidium, and the prevalence is associated with the region and age of dairy cattle. Species identification showed Cryptosporidium andersoni in 36 samples (24.00 %, 19 from NXHAR and 17 from Gansu), Cryptosporidium ryanae in 24 samples (16.00 %, 13 from NXHAR and 11 from Gansu), Cryptosporidium bovis in 70 samples (46.67 %, 41 from NXHAR and 29 from Gansu), and Cryptosporidium parvum in 20 samples (13.33 %, 19 from NXHAR and 1 from Gansu). A DNA sequence analysis of the gp60 gene suggested that all the 20 C. parvum isolates represented subtype IIdA15G1. These findings indicated the presence of zoonotic Cryptosporidium in Gansu and NXHAR. This is the first report of four species of Cryptosporidium (C. andersoni, C. ryanae, C. bovis, and C. parvum) infection in dairy cattle in Gansu province. This is also the first report of C. ryanae infection in dairy cattle in NXHAR. Effective control strategies should be implemented to prevent and control Cryptosporidium infection in dairy cattle and humans.

Molecular characterization of Cryptosporidium spp. and Giardia duodenalis from yaks in the central western region of China

BACKGROUND

Cryptosporidium spp. and Giardia duodenalis are important causes of diarrheal diseases in humans and animals worldwide, and there is an increased interest in the role of animals in the mechanical transmission of these protozoa. To examine the role of yaks in this process, we examined the occurrence and genotypes of Cryptosporidium and G. duodenalis in yaks in western China.

RESULTS

A total of 545 fecal specimens were collected from yaks from nine different counties in the central western region of China. The prevalence for Cryptosporidium spp. and G. duodenalis were 4.0 % (22/545) and 6.0 % (16/545), respectively. Mixed infections of Cryptosporidium and G. duodenalis were also detected in four specimens. The prevalence of both protozoa differed significantly between some age groups, with higher rates of infection in animals < 1 year old. Sequence analysis of the small subunit rRNA (SSU rRNA) gene of the Cryptosporidium isolates identified the species as C. parvum (n = 12), C. bovis (n = 6), C. ryanae (n = 3), and C. ubiquitum (n = 1). Genotyping based on 60-kDa glycoprotein (gp60) gene from five C. parvum isolates identified all as IId with three isolates identified as IIdA15G1, one as IIdA18G1, and one as IIdA19G1. One C. ubiquitum isolate was identified as subtype VIIa. Amongst the G. duodenalis isolates, 16 were identified as assemblage E at the SSU rRNA gene. Four novel glutamate dehydrogenase (gdh) subtypes and two triosephosphate isomerase (tpi) subtypes were found amongst the G. duodenalis assemblage E isolates.

CONCLUSIONS

The presence of C. parvum subtype IIdA15G1, IIdA18G1, and IIdA19G1 isolates further confirms the dominance of the C. parvum IId subtypes in China. These findings also indicate that yaks may be a source of zoonotic Cryptosporidium infection, and this is the first report of G. duodenalis in yaks. The data presented here provides the basis for further genotyping or subtyping studies of G. duodenalis in yaks.

Genotyping and subtyping of Giardia and Cryptosporidium isolates from commensal rodents in China

Cryptosporidium and Giardia are two important zoonotic intestinal parasites responsible for diarrhoea in humans and other animals worldwide. Rodents, as reservoirs or carriers of Cryptosporidium and Giardia, are abundant and globally widespread. In the present study, we collected 232 fecal specimens from commensal rodents captured in animal farms and farm neighbourhoods in China. We collected 33 Asian house rats, 168 brown rats and 31 house mice. 6.0% (14/232) and 8.2% (19/232) of these rodents were microscopy-positive for Giardia cysts and Cryptosporidium oocysts, respectively. All 14 Giardia isolates were identified as Giardia duodenalis assemblage G at a minimum of one or maximum of three gene loci (tpi, gdh and bg). By small subunit rRNA (SSU rRNA) gene sequencing, Cryptosporidium parvum (n = 12) and Cryptosporidium muris (n = 7) were identified. The gp60 gene encoding the 60-kDa glycoprotein was successfully amplified and sequenced in nine C. parvum isolates, all of which belonged to the IIdA15G1 subtype. Observation of the same IIdA15G1 subtype in humans (previously) and in rodents (here) suggests that rodents infected with Cryptosporidium have the potential to transmit cryptosporidiosis to humans.

Prevalence and molecular characterization of Cryptosporidium spp. and Giardia duodenalis in dairy cattle in Ningxia, northwestern China

Background

Cryptosporidium spp. and Giardia duodenalis are important gastrointestinal protists in humans and animals worldwide. In China, bovine cryptosporidiosis and giardiasis are of increasing concern because cattle are important reservoirs of these parasites, which have become potential threats to public health and to large numbers of cattle in recent years.

Results

A total of 1366 fecal samples from the Ningxia Autonomous Region were examined. The overall infection rates for Cryptosporidium spp. and G. duodenalis were 1.61% and 2.12%, respectively. Cryptosporidium was only detected in preweaned calves and adults older than 2 years, whereas G. duodenalis was only detected in calves aged less than 11 months. Cryptosporidium spp. were characterized with a PCR–restriction fragment length polymorphism analysis and DNA sequence analysis of the small subunit rRNA gene. Three Cryptosporidium species were identified: C. parvum (n = 15) and C. bovis (n = 4) in preweaned calves, and C. andersoni (n = 4) in adults aged over 2 years. A DNA sequence analysis of the gp60 gene suggested that the 15 C. parvum isolates all belonged to subtype IIdA15G1. Twenty-nine G. duodenalis isolates were analyzed by DNA sequencing of the triosephosphate isomerase (tpi) and glutamate dehydrogenase (gdh) genes. Two G. duodenalis assemblages were identified, assemblages E (n = 15) and B (n = 4, one subtype B1 and three subtype B2) in preweaned calves, and assemblage E (n = 10) in 3–11-month-old calves.

Conclusions

The predominance of C. parvum detected in preweaned calves and the first identified subtype IIdA15G1 in dairy cattle, and the dominant G. duodenalis assemblage E in this study differed considerably from those found in Henan, Heilongjiang, and Shannxi Provinces. Our findings further confirm the dominance of C. parvum IId subtypes in China.

Occurrence and molecular characterization of Cryptosporidium spp. and Enterocytozoon bieneusi in dairy cattle, beef cattle and water buffaloes in China

Cryptosporidium spp. and Enterocytozoon bieneusi are important protists in a wide range of vertebrate hosts, causing diarrheal diseases. Cattle are considered potential reservoirs of Cryptosporidium infection in humans, although their role in the transmission of E. bieneusi is not clear. In the present work, 793 fecal specimens from dairy cattle, native beef cattle, and water buffaloes on 11 farms in China were examined for the presence of Cryptosporidium spp. and E. bieneusi using nested PCR targeting the small subunit (SSU) rRNA gene of Cryptosporidium spp. and the internal transcribed spacer (ITS) of E. bieneusi. For Cryptosporidium, 144/446 (32.3%) dairy cattle, 44/166 (26.5%) beef cattle, and 43/181 (23.8%) water buffaloes were PCR-positive. Sequence analysis was successful for 213 of the 231 Cryptosporidium-positive isolates; among them 94 had Cryptosporidium andersoni, 61 had Cryptosporidium bovis, 54 had Cryptosporidium ryanae, 2 had a Cryptosporidium suis-like genotype, and 2 had mixed infections of C. bovis and C. ryanae. In dairy and beef cattle, C. andersoni and C. bovis were the most common species, whereas C. ryanae was the dominant species in water buffaloes. The latter species produced SSU rRNA sequences different between cattle and water buffaloes. For E. bieneusi, the infection rate of E. bieneusi in dairy cattle, beef cattle and water buffaloes was 4.9%, 5.4% and 2.2%, respectively. All 35 E. bieneusi-positive specimens were successfully sequenced, revealing the presence of four genotypes: three Group 2 genotypes previously reported in cattle as well as humans (I, J and BEB4) and one Group 1 genotype recently reported in yaks (CHN11). Genotypes I and J were the most common genotypes in dairy and beef cattle, while genotype CHN11 was the only genotype seen in water buffaloes. Thus, the distribution of Cryptosporidium spp. and E. bieneusi in water buffaloes might be different from in dairy and beef cattle in China. These findings indicate that some of the Cryptosporidium species and all four E. bieneusi genotypes identified in bovine animals in the study areas may have zoonotic potential.

Prevalence and molecular characterization of Cryptosporidium in goats across four provincial level areas in China

This study assessed the prevalence, species and subtypes of Cryptosporidium in goats from Guangdong Province, Hubei Province, Shandong Province, and Shanghai City of China. Six hundred and four fecal samples were collected from twelve goat farms, and the overall infection rate was 11.4% (69/604). Goats infected with Cryptosporidium were found in eleven farms across four provincial areas, and the infection rate ranged from 2.9% (1/35) to 25.0% (9/36). Three Cryptosporidium species were identified. Cryptosporidium xiaoi (45/69, 65.2%) was the dominant species, followed by C. parvum (14/69, 20.3%) and C.ubiquitum (10/69, 14.5%). The infection rate of Cryptosporidium spp. was varied with host age and goat kids were more susceptible to be infected than adult goats. Subtyping C.parvum and C.ubiquitum positive samples revealed C. parvum subtype IIdA19G1 and C. ubiquitum subtype XIIa were the most common subtypes. Other C. parvum subtypes were detected as well, such as IIaA14G2R1, IIaA15G1R1, IIaA15G2R1 and IIaA17G2R1. All of these subtypes have also been detected in humans, suggesting goats may be a potential source of zoonotic cryptosporidiosis. This was the first report of C. parvum subtypes IIaA14G2R1, IIaA15G1R1 and IIaA17G2R1 infecting in goats and the first molecular identification of C.parvum and its subtypes in Chinese goats.

First report of Cryptosporidium spp. in white yaks in China

BACKGROUND

Cryptosporidium is an enteric apicomplexan parasite, which can infect yaks, leading to reduction of milk production and poor weight gain. White yak (Bos grunniens) is a unique yak breed inhabiting only in Tianzhu Tibetan Autonomous County, Gansu province, northwestern China. The objective of the present study was to molecularly determine Cryptosporidium infection and species in white yaks.

FINDINGS

Seventy-six fecal samples from white yaks in Tianzhu Tibetan Autonomous County, Gansu province were collected. The small subunit ribosomal RNA (SSU rRNA) gene of each sample was amplified using nested PCR and sequenced. The Cryptosporidium species was determined by comparison of the obtained sequences with that of corresponding Cryptosporidium sequences available in GenBank by BLAST (http://www.ncbi.nlm.nih.gov/BLAST/) and phylogenetic analysis with maximum likelihood (ML) using PAUP*. The overall prevalence of Cryptosporidium infection in white yak was 5.26% (4/76). Species identification showed C. andersoni in one sample (collected in September), and C. bovis in three samples (one collected in November and two collected in September).

CONCLUSIONS

The present investigation revealed the existence of Cryptosporidium infection in white yaks in China, for the first time, and two Cryptosporidium species, namely C. andersoni and C. bovis, were identified. These findings extend the host range for Cryptosporidium spp., and also provide base-line information for further studies of molecular epidemiology and control of Cryptosporidium infection in the unique white yaks.

Cryptosporidium species in sheep and goats from Papua New Guinea

Species of Cryptosporidium are extensively recognised as pathogens of domesticated livestock and poultry, companion animals, wildlife, and are a threat to public health. Little is known of the prevalence of Cryptosporidium spp. in humans, domesticated animals or wildlife in Papua New Guinea (PNG). The aim of the present study was to screen sheep and goats for Cryptosporidium using molecular tools. A total of 504 faecal samples were collected from sheep (n=276) and goats (n=228) in village, government and institutional farms in PNG. Samples were screened by nested PCR and genotyped at the 18S rRNA and at the 60kDa glycoprotein (gp60) loci. The overall prevalences were 2.2% for sheep (6/278) and 4.4% (10/228) for goats. The species/genotypes identified were Cryptosporidium hominis (subtype IdA15G1) in goats (n=6), Cryptosporidium parvum (subtypes IIaA15G2R1and IIaA19G4R1) in sheep (n=4) and in goats (n=2), Cryptosporidium andersoni (n=1) and Cryptosporidium scrofarum (n=1) in sheep, Cryptosporidium xiao (n=1) and Cryptosporidium rat genotype II (n=1) in goats. This is the first report of Cryptosporidium spp. identified in sheep and goats in PNG. Identification of Cryptosporidium in livestock warrants better care of farm animals to avoid contamination and illness in vulnerable population. The detection of zoonotic Cryptosporidium in livestock suggests these animals may serve as reservoirs for human infection.