Molecular characterisation of Cryptosporidium isolates from rivers,water treatment plants and abattoirs in Ibadan,Nigeria

To understand the molecular characteristics of Cryptosporidium species contaminating rivers, water treatment plants and abattoirs in Ibadan Nigeria, water samples were obtained from ten rivers used for household and agricultural purposes, three major functional water treatment plants and three major abattoirs located within Ibadan metropolis during dry and rainy seasons between November, 2016 to October, 2017. Obtained samples were examined for Cryptosporidium oocysts using microscopy after using modified formalin–ether concentration method and modified acid-fast staining. Cryptosporidium oocysts were detected in samples from five rivers with mean oocyst count/field ranging from 7.70 ± 0.57–1.34 ± 0.57, oocysts were also detected in samples from two abattoirs with mean oocyst count/field ranging from 4.60 ± 0.33–2.50 ± 0.33. Genomic DNA were extracted from microscopy positive river and abattoir samples using sucrose gradient purification method and genotypes and subtypes of parasites were detected by nested PCR amplification and nucleotide sequence analysis of both 18S rRNA and 60-kDa glycoprotein (gp60) genes. Cryptosporidium parvum, C. muris and C. fragile were the only genotypes detected in some river samples, while gp60 gene sequence analysis showed that the C. parvum strain detected was subtype IIa. This study provides evidence that rivers used for household and agricultural purposes in studied area may be potential reservoirs and infection sources for Cryptosporidium species and zoonotic subtypes of public health importance.     

Detection of a novel genotype of Cryptosporidium in Antarctic pinnipeds

A study was conducted to investigate the presence of Cryptosporidium and Giardia in Antarctic marine mammals. A total of 270 faecal samples from different species of pinnipeds from different locations in the South Shetland Islands and Antarctic Peninsula were analysed by immunofluorescence microscopy and PCR. Cryptosporidium was detected by PCR in three samples from Southern elephant seals (Mirounga leonina) and 2 Weddell seals (Leptonychotes weddellii). However, no oocysts were observed in any of the samples by immunofluorescence microscopy. Molecular characterisation of the isolates, using the 18S rDNA, the HSP70 and the COWP loci, revealed the presence of a Cryptosporidium sp., previously reported from an Antarctic Southern elephant seal, in the elephant seals and a novel genotype in Weddell seals. Giardia could not be detected in any of the samples analysed.     

A study of neonatal cryptosporidosis of foals in New Zealand

Abstract

AIM: To assess the occurrence of Cryptosporidium oocysts in faecal specimens from foals, and investigate an outbreak of neonatal cryptosporidiosis in foals revealed in the course of the study.

METHODS: Faecal specimens from foals received by a diagnostic veterinary laboratory in New Zealand between 2006 and 2007 were submitted to Massey University and tested microscopically for the presence of Cryptosporidium oocysts. The Cryptosporidium isolates in the oocyst-positive specimens were genetically identified to species level. In addition, specimen submission data from the participating laboratory for 2005–2007 were examined. In the course of the study, the identification of one Cryptosporidium-positive specimen triggered an on-farm investigation.

RESULTS: Twelve faecal specimens submitted by the participating laboratory between 2006 and 2007 were tested further, and three were positive for C. parvum. Specimen submission records indicated a total of 67 faecal specimens were tested for Cryptosporidium by the participating laboratory between 2005 and 2007; 12 (18%) were positive. The on-farm investigation on a broodmare farm revealed a high incidence of neonatal diarrhoea in foals; C. parvum was the only enteropathogen found in the faeces of 4/4 affected foals examined. The diarrhoea in all those foals was self-limiting, manifesting during the second week of life, resembling foal heat diarrhoea, and accompanied by a short but intense period of shedding oocysts.

CONCLUSIONS AND CLINICAL RELEVANCE: The fact that Cryptosporidium parasites were identified in 18% of faecal specimens from foals analysed for this agent in 2005–2007 by the participating laboratory indicated that infection with this agent in foals is not uncommon.

Collectively, the results of this and previous studies performed in New Zealand indicate C. parvum is a cause of diarrhoea in newborn foals, potentially accounting for a proportion of cases empirically diagnosed as foal heat diarrhoea. It is therefore advisable to take precautions when handling diarrhoeic foals, until this potentially zoonotic agent is ruled out in the laboratory.     

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

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.     

Cryptosporidium hominis Subtypes and Enterocytozoon bieneusi Genotypes in HIV‐Infected Persons in Ibadan,Nigeria

Cryptosporidium and Enterocytozoon are common opportunistic pathogens in HIV+ patients in developing countries, especially those do not have access to antiretroviral therapy. To determine the distribution of genotypes/subtypes of Cryptosporidium and Enterocytozoon bieneusi, faecal specimens were collected from 132 HIV+ persons attending a tertiary hospital in Ibadan, Nigeria. By polymerase chain reaction, eight and ten patients were identified as positive for Cryptosporidium spp. and E. bieneusi, respectively. Seven of the Cryptosporidium specimens were identified as C. hominis, while the remaining one as the new species C. viatorum recently identified in the United Kingdom. DNA sequencing of the 60‐kDa glycoprotein gene showed that the C. hominis belonged to three common subtype families: Ia (in three patients), Ib (in one patient) and Ie (in one patient). In contrast, DNA sequencing of the E. bieneusi internal transcribed spacer products showed the occurrence of genotypes associated with both humans (Peru 8 in one patient, Nig2 in two patients and a new genotype in one patient) and animals (D in one patient and Type IV in five patients). Low CD4+ cell count was identified as a risk factor for both cryptosporidiosis and microsporidiosis.     

Prevalence and age-related infection of Cryptosporidium suis, C. muris and Cryptosporidium pig genotype II in pigs on a farm complex in the Czech Republic

A total of 413 pig faecal samples were collected from pre-weaners (119), starters (131), pre-growers (123) and sows (40) from a farm with a closed breeding system segmented into two breeding complexes and a growing complex in the region of Vysočina, Czech Republic and screened for the presence of Cryptosporidium using staining methods and genotyping (SSU rRNA). Cryptosporidium oocysts were detected by microscopy in the faeces of 21.1% of the samples (87/413). Sequence analyses and RFLP identified C. suis in 44, Cryptosporidium pig genotype II in 23 and C. muris in 2 samples. No mixed infections were found.Pigs under 7 weeks of age were infected with C. suis only. Cryptosporidium pig genotype II was found in animals from 7 weeks of age. No relationship was found between diarrhoea and any Cryptosporidium infection in any of the different age groups (P < 0.05). The pre-weaned pigs shed significantly more Cryptosporidium oocysts than older pigs and it was associated with C. suis infection.     

Cryptosporidium species detected in calves and cattle in Dagoretti,Nairobi, Kenya

A total of 1,734 cattle faecal samples from 296 dairy-keeping households were collected from urban settings in Nairobi, Kenya. Modified Ziehl–Neelsen staining method and an immunofluorescence assay were used to identify those samples with Cryptosporidium oocyst infection. Oocysts from positive faecal samples were isolated by Sheather's sucrose flotation method and picked from the concentrate using cover slips. Genomic DNA was extracted from 124 of the faecal samples that were positive for Cryptosporidium and was used as template for nested PCR of the 18S rRNA gene. Twenty-five samples (20 %) were PCR-positive for Cryptosporidium, and 24 of the PCR products were successfully cloned and sequenced. Sequence and phylogenetic analysis identified 17 samples (68 %) as Cryptosporidium parvum-like, four samples (16 %) as Cryptosporidium ryanae, three samples (12 %) as Cryptosporidium andersoni and one sample (4 %) as Cryptosporidium hominis. To the best of our knowledge, this is the first genotyping study to report C. parvum-like, C. andersoni and C. hominis in cattle from Kenya. The results of this study show Cryptosporidium infections in calves and cattle may be potential zoonotic reservoirs of the parasite that infects humans.     

The prevalence of <Emphasis Type="Italic">Cryptosporidium</Emphasis> species in diarrhoeic lambs in Kars province and potential risk factors

This study was carried out to determine the prevalence of Cryptosporidium species in diarrhoeic lambs and investigate some risk factors in Kars province (Northeastern region of Anatolia) in Turkey. Four hundred faecal samples were taken from the rectums of clinically diarrhoeic and aged to 1-month-old lambs from 34 sheep farms in 20 villages in March-April 2007 and examined by using the modified acid-fast staining technique. The prevalence of Cryptosporidium species was found as 38.8% (155/400). Cryptosporidium oocysts were detected in 90.0% (18/20) of villages and in 76.5% (26/34) of the sheep farms. Infection rates were detected as: 44.4% (67/151) in 1-week-old lambs, 37.5% (39/104) in 2-week-old lambs, 40.0% (38/95) in 3-week-old lambs, and 22.0% (11/50) in 4-week-old lambs. Farms classified according to their zoohygienic conditions and fine, average and bad conditioned farms were contaminated with Cryptosporidium with the percentages of 14.7%, 20.6% and 41.2%, respectively. Clinical cryptosporidiosis was determined in 35.0% of the villages (7/20) and in 29.4% of the sheep farms (10/34), Cryptosporidium oocysts were found in 81.3% of the lambs (91/112) in these farms. Cryptosporidiosis may be a major epidemiological significance in lambs in Kars province, and suggests that naturally infected lambs may be reservoirs of Cryptosporidiosis infections for calves even for humans too.     

Prevalence and molecular characterization of Cryptosporidium spp. in dairy cattle from farms in China

Fecal samples of 2,056 dairy cattle from 14 farms were collected in three geographical regions of China and stained using a modified acid-fast staining technique to identify Cryptosporidium oocysts. A total of 387 (18.82%) positive samples were identified and further analyzed by polymerase chain reaction (PCR) using primers designed to amplify DNA fragments from the small subunit ribosomal RNA. The PCR products were sequenced and the sequences were deposited in the GenBank database under accession numbers EU369377-84 and GU070730-33. Phylogenetic analysis was performed and a distances matrix generated from these sequences confirmed the existence of Cryptosporidium (C.) parvum ''mouse'' genotype, C. bovis, C. andersoni, C. hominis, and C. serpentis in cattle. These results represent the first report on the prevalence and genetic identification of Cryptosporidium species, and may contribute to a better understanding of the epidemiology of Cryptosporidium in cattle in China.     

Captive Agamid lizards in Germany: Prevalence,pathogenicity and therapy of gastrointestinal protozoan and helminth infections

Reptiles are becoming popular pets in many parts of the world. They are also known to harbor numerous gastrointestinal parasites. We used faecal smears to examine 748 stool samples from 14 different agamid lizard species. In addition, we used coproantigen ELISA tests (11 samples) and immunofluorescence assays (IFA) (19 samples) to detect reptile Cryptosporidium infections. In 28 cases, veterinarians requested therapy to treat oxyurid- and/or Isospora amphiboluri-infections and resent fecal samples after proposed therapy and anti-parasitic treatments had been applied. We also performed complete dissections of 24 deceased agamas in order to specify protozoan and helminth parasite infections.Overall, the examined fecal samples contained 6 different taxa. Oxyurids (Pharyngodonidae) were the most prevalent nematodes (41.2%), followed by I. amphiboluri (17.0%), Entamoeba spp. (0.8%), Choleoeimeria spp. (0.5%), Trichomonas spp. (0.3%), Cryptosporidium spp. (0.3%) and Strongyloides-like nematodes (0.1%). I. amphiboluri infections were significantly more prevalent (Chi-square test: χ² = 21,5, df = 1, P < 0.001) in juvenile agamid lizards (31.9%) than in adults (14.2%). One of 11 (9.1%) coproantigen ELISA-examined samples was positive for Cryptosporidium. In 10.5% of the samples we found oocysts of Cryptosporidium. Thirteen (54.2%) of necropsied agamid lizards were infected with endoparasites and it is likely that three (12.5%) of them died due to severe parasitic infections. 74.0% of the samples that were submitted after therapy had been applied were negative. The high prevalences and pathological findings of several clinical parasitoses observed in these exotic reptiles calls for more detailed investigations on agamid gastrointestinal parasite fauna.     

Occurrence of Cryptosporidium and Giardia on beef farms and water sources within the vicinity of the farms on Prince Edward Island, Canada

The objectives of this study were to determine the prevalence and assemblages of Giardia and species of Cryptosporidium on beef farms in Prince Edward Island (PEI), Canada, including the water sources associated with the farms, and to determine risk factors for infection of cattle with these parasites. Twenty beef farms were selected based on the presence of surface water < 500 m from the barn. Prevalence was determined by direct immunofluorescence microscopy, while genotyping and species determination were performed by nested-PCR and DNA sequencing. Giardia was detected in 42% (95% CI: 38-46%) of fecal samples from 100% farms while Cryptosporidium was detected in 17% (95% CI: 14-19%) of fecal samples from 80% of farms. The most predominant Giardia assemblage isolated was the livestock specific assemblage E (89%). The zoonotic assemblages A and B were found in 4 and 7% of the Giardia isolates that were genotyped, respectively. The Giardia assemblages were detected equally between the cows and calves examined. Overall, the most common Cryptosporidium species detected in this study was Cryptosporidium andersoni (49%), predominantly found in cattle >6 mo of age, while most Cryptosporidium bovis and Cryptosporidium pestis (previously Cryptosporidium parvum ‘bovine genotype’) isolates were detected in calves ≤ 6 mo of age. All Cryptosporidium ryanae isolates (four) were found in calves. Giardia cysts and Cryptosporidium oocysts were detected in 14 and 93% of surface water samples of 14 farms, respectively. Cryptosporidium oocysts were detected in three (15%) ground water samples of 20 farms. One Cryptosporidium-positive water sample, which was the only surface water sample amenable to genotyping, contained C. parvum. The farm-level risk factors investigated in this study, age of animals and location of the farm, were not associated with the risk of infection in cattle with either Cryptosporidium spp. or Giardia duodenalis.We conclude that beef cattle are a potential reservoir of Cryptosporidium spp. and G. duodenalis that could contaminate source water. There is the possibility of further transmission to humans on PEI if the source water is not properly treated prior to consumption.     

Molecular characterisation of Cryptosporidium isolates from pet reptiles

In this study, we investigated the presence of Cryptosporidium in 171 faecal samples from reptiles commonly used as pet animals. These include lizards belonging to the genera Eublepharis, Pogona, Chlamydosaurus, Hemiteconyx, Teratoscincus, Tiliqua, Iguana, and Chamaeleo, snakes of the genera Lampropeltis, Elaphe, Python, Boa and Corallus, and tortoises belonging to the genera Testudo and Kinixys. Cryptosporidium oocysts were detected by immunofluorescence using a commercially available kit and cryptosporidial DNA by amplification of a polymorphic fragment of the 18S rDNA and the HSP70 locus.Cryptosporidium was detected in 38.6% and 25.1% of the samples analysed by immunofluorescence and PCR, respectively. Molecular characterisation of the isolates confirmed that C. serpentis and C. varanii (syn. C. saurophilum) are the main species involved in infection in pet reptiles but also showed the presence of C. parvum and C. muris, as well as other species or genotypes of this parasite including the Cryptosporidium mouse genotype and Cryptosporidium tortoise genotype previously described in reptiles. In addition, a Cryptosporidium sp. was isolated from a chameleon and a python.     

Zoonotic Cryptosporidium parvum in Romanian newborn lambs (Ovis aries)

This study was undertaken to investigate the occurrence and public health significance of Cryptosporidium species/genotypes and subtypes in a newborn lambs. A total of 175 diarrheic fecal samples from lambs (younger than 21 days) were collected in seven sheep flocks located in western Romania, and were microscopically examined for the presence of Cryptosporidium oocysts after staining with modified Ziehl–Neelsen technique. Twenty-four (13.7%) fecal samples were tested Cryptosporidium positive by microscopy and were subjected for molecular characterization. All positive samples were successfully amplified through a nested polymerase chain reaction (PCR) of the small subunit (SSU) rRNA gene (18S). Cryptosporidium species were determined by restriction fragment length polymorphism (RFLP) analysis of the secondary PCR products using the conventional SspI and VspI restriction enzymes. The identified species were: Cryptosporidium parvum (20/24), C. ubiquitum (2/24) and C. xiaoi (2/24), respectively. PCR-RFLP results for C. ubiquitum and C. xiaoi isolates were confirmed by DNA sequencing. Subsequently, subtyping of seven randomly selected C. parvum isolates, based on sequence analysis of the GP60 gene, revealed the presence of five different subtypes (IIaA17G1R1, IIaA16G1R1, IIdA20G1, IIdA24G1 and IIdA22G2R1) belonging in two zoonotic subtype families (IIa and IId). These findings may suggest the potential role of the newborn lambs as a source for human cryptosporidiosis. This is the first published report about the presence of C. ubiquitum and C. xiaoi in lambs from Romania.     

Health screening for a translocation of captive-reared tuatara (Sphenodon punctatus) to an island refuge

AIMS: To screen tuatara undergoing translocation from a captive crèche to an island refuge for evidence of health and known diseases, and apply basic epidemiological techniques to assess the significance of disease test results.

METHODS: Tuatara (n=353) were physically examined and samples were taken from a random selection (n=30) for estimated white cell counts, screening for haemoparasites, and culture for Salmonella, Yersinia, Aeromonas and Campylobacter spp. Direct faecal smears were carried out on-site, and faecal floats were later performed to assess levels of endoparasitism with helminths and protozoa (n=69). Modified Ziehl-Neelsen staining was used to screen faecal smears, and positive specimens were further screened using an immunofluorescence antibody (IFA) test for Cryptosporidium oocysts.

RESULTS: There was no evidence of external parasites on any of the animals examined and only one animal had a gross abnormality. All estimated white cell counts were in the range 2.8– 17.5 × 10⁹/L. No haemoparasites were observed. There were no enteric pathogens cultured, indicating the intestinal carriage of these bacteria in the tuatara was 9.4%. Of the 69 individual faecal samples examined, 12 (17%) had unidentified coccidial oocysts, 21 (30%) had nematode ova of various kinds, and 12 (17%) had intestinal carriage of motile protozoa consistent with Trichomonas spp and another unidentified organism. Nineteen (28%) tuatara had acid-fast oocysts present; however, IFA staining failed to detect any Cryptosporidium oocysts.

CONCLUSIONS: Our understanding of the diversity of gastrointestinal endoparasites affecting tuatara is inadequate as many of the parasite ova seen could not be identified. This is the first record of tuatara as a host for Trichomonas spp of protozoa in the gastrointestinal tract.     

Genotyping of Cryptosporidium parvum isolates in bovine population in Kolkata and characterization of new bovine genotypes

Cryptosporidium infection may have adverse effect in health and production potential of cattle herd. The exact profile of Cryptosporidium infection in bovine population of India in general, particularly from Kolkata is scarce. We here report systematic investigation of clinical and genetic profiling of promiscuous Cryptosporidium infection in selected representative cattle farms from Kolkata as well as some surrounding local areas. The current study was conducted in the period of October to September, 2000–2001 with 149 diarrhoeic and non-diarrhoeic cattle of different age groups from two Government cattle farms, Harringhata Cattle Unit and Kalyani State Livestock Farm and animals raised by local farmers. Among these 149 samples, diarrhoea was recorded in 79 cases (53%) and non-diarrhoeic in 70 (46.9%). Out of 149 faecal samples screened microscopically, 32.9% from diarrhoeic faecal samples and 7.1% from healthy faecal samples revealed the presence of oocysts. Cryptosporidium genus was confirmed by DNA typing with nested PCR. The PCR-RFLP analysis was carried out for genotype identification. In course of PCR-RFLP, unique band patterns were obtained in two of our samples. The unusual RFLP products were characterized by DNA sequencing and homology analysis with other reported variants. This is the first report of identification and characterization of such a variant from the area of present investigation. Further study will be required to understand the phylogenetic origin and functional significance in virulence and morbidity of this genotype.     

Comparative evaluation of Cryptosporidium infection in malnourished and well-nourished children: Parasitic infections are affected by the interaction of nutritional status and socio-demographic characteristics

Cryptosporidium, as a small protozoan parasite, is a leading cause of persistent diarrhea in children in developing countries and has both a short and long-term impact on the growth of children. In the present study, Cryptosporidium infection was compared in malnourished and well-nourished children by modified acid-fast staining, nested-polymerase chain reaction (nested-PCR) and loop-mediated isothermal amplification (LAMP) methods. As a case-control study, Cryptosporidium infection in 94 malnourished children was evaluated and compared with those of 188 age and gender-matched well-nourished children. Oocysts of Cryptosporidium were detected by modified acid-fast staining method. The extracted DNA was amplified by nested-PCR and LAMP techniques. In addition, positive amplicons were directly sequenced for phylogenetic analysis. Cryptosporidium oocysts were found in the stools of two (2.12 %) children who were hospitalized and had diarrhea by nested-PCR while three isolates (3.2 %) were found by LAMP. Cryptosporidium-positive children were more malnourished compared to those who were negative for Cryptosporidium infection but this important finding was not statistically significant. C. parvum was the main species of Cryptosporidium detected in malnourished children in northwest Iran. LAMP can be considered as a sensitive field monitoring assay in patients with low parasite burden. Nutritional status and socio-demographic factors may have interactive effects on the incidence and severity of parasitic diseases.     

An outbreak of massive mortality among farm rabbits associated with Cryptosporidium infection

Cryptosporidium in farm rabbits is not often recognised due to a low prevalence and asymptomatic course of infection. Nonetheless, incidences of fatal diarrhoeic diseases are frequently noticed in the rabbitries. In this article, we report an outbreak where there was massive mortality among farm rabbits associated with Cryptosporidium infection. The disease was characterised by profuse diarrhoea resulting in the death of rabbits. A pooled faecal sample was screened for a presence of parasites using microscopy methods. In the tested sample no other parasites other than Cryptosporidium oocysts were found. Further identification of the parasite species was performed at a molecular level, using the 18 SSU rRNA, COWP and LIB13 PCR followed by a subtyping at the GP60 gene locus. Sequence analysis of GP60 gene fragment revealed the presence of a novel subtype VbA24 of Cryptosporidium cuniculus. In this outbreak a Cryptosporidium protozoan parasite played a major role in the etiology of the gastrointestinal disorders in rabbits resulting in massive mortality of the infected animals.     

Cryptosporidium scrofarum n. sp. (Apicomplexa: Cryptosporidiidae) in domestic pigs (Sus scrofa)

We describe the morphological, biological, and molecular characteristics of Cryptosporidium pig genotype II and propose the species name Cryptosporidium scrofarum n. sp. to reflect its prevalence in adult pigs worldwide. Oocysts of C. scrofarum are morphologically indistinguishable from C. parvum, measuring 4.81–5.96 μm (mean = 5.16) × 4.23–5.29 μm (mean = 4.83) with a length to width ratio of 1.07 ± 0.06 (n = 400). Oocysts of C. scrofarum obtained from a naturally infected pig were infectious for 8-week-old pigs but not 4-week-old pigs. The prepatent period in 8-week-old Cryptosporidium-naive pigs was 4–6 days and the patent period was longer than 30 days. The infection intensity of C. scrofarum in pigs was generally low, in the range 250–4000 oocysts per gram of feces. Infected pigs showed no clinical signs of cryptosporidiosis and no pathology was detected. Cryptosporidium scrofarum was not infectious for adult SCID mice, adult BALB/c mice, Mongolian gerbils (Meriones unguiculatus), southern multimammate mice (Mastomys coucha), yellow-necked mice (Apodemus flavicollis), or guinea pigs (Cavia porcellus). Phylogenetic analyses based on small subunit rRNA, actin, and heat shock protein 70 gene sequences revealed that C. scrofarum is genetically distinct from all known Cryptosporidium species.     

Identity and public health potential of Cryptosporidium spp. in water buffalo calves in Egypt

Little is known about the diversity and public health significance of Cryptosporidium species in water buffaloes. In this study, we examined the distribution of Cryptosporidium spp. in water buffalo calves in Egypt. Rectal fecal specimens from 179 calves and 359 adults were screened microscopically for Cryptosporidium oocysts using modified Ziehl–Neelsen stain. Cryptosporidium spp. in 17 microscopy-positive specimens from calves were genotyped by DNA sequence analysis of the small-subunit rRNA gene, and Cryptosporidium parvum was subtyped by sequence analysis of the 60 kDa glycoprotein gene. Cryptosporidium ryanae was found in 10 specimens and C. parvum in 7 specimens, with the former belonging to the newly identified C. ryanae buffalo variant and the latter belonging to the subtypes IIdA20G1 (in 5 specimens) and IIaA15G1R1 (in 2 specimens). The prevailing occurrence of C. ryanae and the subtype family IId of C. parvum and the absence of C. bovis and C. andersoni represent some features of Cryptosporidium transmission in water buffaloes in Egypt.     

Prevalence and genetic characterization of Giardia spp. and Cryptosporidium spp. in dogs in Iqaluit,Nunavut, Canada

There are few epidemiologic studies on the role of dogs in zoonotic parasitic transmission in the Circumpolar North. The objectives of this study were to: (a) estimate the faecal prevalence of Giardia spp. and Cryptosporidium spp. in dogs; (b) investigate potential associations between the type of dog population and the faecal presence of Giardia spp. and Cryptosporidium spp.; and (c) describe the molecular characteristics of Giardia spp. and Cryptosporidium spp. in dogs in Iqaluit, Nunavut. We conducted two cross‐sectional studies in July and September 2016. In July, the team collected daily faecal samples for 3 days from each of 20 sled dogs. In September, the team collected three faecal samples from each of 59 sled dogs, 111 samples from shelter dogs and 104 from community dogs. We analysed faecal samples for the presence of Giardia spp. and Cryptosporidium spp. using rapid immunoassay and flotation techniques. Polymerase chain reaction (PCR) and sequencing of target genes were performed on positive faecal samples. Overall, the faecal prevalence of at least one of the target parasites, when one faecal sample was chosen at random for all dogs, was 8.16% (CI: 5.52–11.92), and for Giardia spp. and Cryptosporidium spp., prevalence was 4.42% (CI: 2.58–7.49) and 6.12% (CI: 3.88–9.53), respectively. The odds of faecal Giardia spp. in sled dogs were significantly higher than those in shelter and community dogs (OR 10.19 [CI: 1.16–89.35]). Sequence analysis revealed that 6 faecal samples were Giardia intestinalis, zoonotic assemblage B (n = 2) and species‐specific assemblages D (n = 3) and E (n = 1), and five faecal samples were Cryptosporidium canis. Giardia intestinalis is zoonotic; however, Cryptosporidium canis is rare in humans and, when present, usually occurs in immunosuppressed individuals. Dogs may be a potential source of zoonotic Giardia intestinalis assemblage B infections in residents in Iqaluit, Nunavut, Canada; however, the direction of transmission is unclear.