<Emphasis Type="Italic">Cryptosporidium</Emphasis> spp. parasitize exotic birds that are commercialized in markets,commercial aviaries,and pet shops

The purpose of this study was to genetically characterize and phylogenetically analyze the Cryptosporidium spp. isolated from exotic birds commercialized in popular markets, commercial aviaries, and pet shops located in Rio de Janeiro, Brazil. Fecal samples from individually housed birds were collected and subjected to centrifuge–flotation technique using saturated sugar solution. DNA was isolated from Cryptosporidium positive samples, and 18S subunit rDNA was amplified and processed using nested-polymerase chain reaction (PCR). To identify the protozoan species, the PCR amplicons were used for restriction fragment length polymorphism and sequencing analyses. Of the 103 analyzed fecal samples, seven (6.8%) were positive for Cryptosporidium oocysts. Sequencing and further phylogenetic analyses allowed us to identify the following species: Cryptosporidium parvum in Bengalese finch (Lonchura striata domestica) and avian genotype III in Java sparrow (Padda oryzivora) and cockatiel (Nymphicus hollandicus). The sequences of the Cryptosporidium spp. isolated from canaries (Serinus canarius) were not identifiable within the groups of known species, but they presented a higher genetic similarity with C. parvum. This is the first report in Brazil showing that C. parvum parasitizes Bengalese finches and that avian genotype III parasitizes Java sparrows.     

Prevalence of Cryptosporidium spp. infection in some dairy herds of Mashhad (Iran) and its association with diarrhea in newborn calves

A 1:1 matched case-control study of calves less than 1 month of age was carried out by weekly visits to some dairy farms in Mashhad, Iran. Fecal samples were collected over a 6-month period from a total of 112 calves with clinical signs of diarrhea and from 112 matched animals without clinical signs of diarrhea as assessed by a scoring system. The samples were investigated for the presence of Cryptosporidium spp. oocysts by modified Ziehl–Neelson staining method. Cryptosporidium spp. oocysts were present in 51.8% of calves with diarrhea and in 21.4% of the controls. Among diarrheic calves, the highest prevalence of Cryptosporidium oocyst shedding was in age group 8–14 days (74.5%), and the lowest prevalence of Cryptosporidium oocyst shedding was in age group 22–30 days (23.8%). The McNemar test in all sampled calves showed significant differences in odds ratio for the presence of Cryptosporidium spp. in fecal samples, and the excretion of parasite in the feces of scouring calves was significantly higher (odds ratio 6.1) than in healthy calves. Differences between animals with and without diarrhea were statistically significant for age groups 1–7 and also 8–14 day-old calves. These results indicate that in these industrial dairy farms in Mashhad, infections by Cryptosporidium should be considered as a potential cause for newborn calf.     

Development of an immunomagnetic bead separation-coupled quantitative PCR method for rapid and sensitive detection of Cryptosporidium parvum oocysts in calf feces

Cattle feces are the environmental vehicle for the zoonotic Cryptosporidium oocysts, but there are drawbacks associated with reliability of the existing methods for the detection of oocysts in the feces. Quantification of the immunomagnetic bead separation (IMS) coupled with real-time TaqMan PCR (qPCR) was accomplished by comparing the fluorescence signals obtained from the calf fecal samples of Cryptosporidium parvum oocysts with those obtained from standard dilutions of C. parvum oocysts. TaqMan qPCR assays were developed for the detection of C. parvum based on 18S rDNA gene. This IMS-qPCR assay allowed a reliable quantification of C. parvum oocysts over seven orders of magnitude with a baseline sensitivity of 8.7 oocysts. The newly developed IMS-qPCR technique proved specific as confirmed by negative reactivity against a wide panel of non-parvum Cryptosporidium oocysts. As a field application, experimentally infected calves (15 infected and 9 non-infected) were screened for oocysts shedding on 16, 18, and 21 days postinfection. Acid-fast staining microscopy of infected calves revealed oocysts in the feces of 11, 7, and 4 calves, respectively, compared to 15, 15, and 12 in case of screening by IMS-qPCR. Taken together, the proposed IMS-qPCR method significantly improved the diagnostic capacity for C. parvum infection in calves, making the technique a useful, sensitive, reliable, and time-saving.     

Molecular characterization of <Emphasis Type="Italic">Cryptosporidium</Emphasis> from animal sources in Qinghai province of China

The presence of Cryptosporidium oocysts in 20 zoo animals of the Xining Zoo, 16 farm yaks and 42 farm goats in Qinghai province, China was investigated by an immunofluorescence test (IFT). The species and/or genotypes were determined by nested polymerase chain reaction (PCR) and sequence analysis of a fragment of the small subunit (SSU) rRNA gene. Cryptosporidium oocysts were found in 16 zoo animals, 2 yaks, and 15 goats by IFT. The IFT positive samples were further investigated by PCR, and 16 of them were found to be positive by that method also. Sequence analysis of the PCR products derived from Cryptosporidium oocysts from Black leopard (Panthera pardus), Heijing He (Grus nigricollis), Barbary sheep (Ammotragus lervia), Takin (Budorcas taxicolor), Lesser panda (Ailurus fulgens), and White-eared pheasant (Crossoptilon crossoptilon) fecal samples matched that of Cryptosporidium parvum mouse genotype. Sequence analyses of other PCR products were consistent with cervine genotype Cryptosporidium from Ibex (Capra ibex), a novel Cryptosporidium genotype from a wild yak (Bos mutus), C. bovis–like genotype from one goat sample and also a novel Cryptosporidium genotype from one other separate goat sample. The present work reports the first data on Cryptosporidium infections in animals from the Qinghai province of mountainous central western China and the first findings of the ‘cervine’ genotype in Capra ibex, C. bovis–like genotype and the new Cryptosporidium spp. in farm goat and in wild yak.     

Evaluation of an Immunochromatographic Dip-Strip Test for the Detection of Cryptosporidium Oocysts in Stool Specimens

The study presented here examined the efficacy of a commercially available qualitative immunochromatographic assay for detecting Cryptosporidium oocysts in stool samples. A total of 75 samples were tested, including 50 positive for Cryptosporidium spp. by acid-fast stain, 20 positive for other parasites (Blastocystis hominis, Endolimax nana, Entamoeba coli, Giardia lamblia, Ascaris lumbricoides, Strongyloides stercoralis and Trichuris trichiura), and five negative samples. The observed sensitivity was 98%, while specificity was 100%; the detection threshold was near 1,000 oocysts/ml. Correctly diagnosed positive samples included Cryptosporidium parvum genotypes 1 and 2, whereas the single false-negative sample corresponded to a Cryptosporidium meleagridis infection. Electronic Publication     

Identification and determination of the viability of Giardia lamblia cysts and Cryptosporidium parvum and Cryptosporidium hominis oocysts in human fecal and water supply samples by fluorescent in situ hybridization (FISH) and monoclonal antibodies

In the present study, fluorescent in situ hybridization (FISH) and monoclonal antibodies (MAbs) were evaluated for species-specific detection and viability determination of Giardia lamblia, Cryptosporidium parvum, and Cryptosporidium hominis in human fecal and water supply samples. A total of 50 fecal human samples positive for G. lamblia cysts, 38 positive for C. parvum, and 23 positive for C. hominis were studied. Also, 18 water supply samples positive for Giardia spp. and Cryptosporidium spp. by the United States Environmental Protection Agency (USEPA) Method 1623 were studied by FISH and fluorescein isothiocyanate (FITC)-conjugated MAbs. Eighteen percent of the fecal samples parasitologically positive for G. lamblia presented viable and nonviable cysts, and 5% of those positive for Cryptosporidium spp. presented viable and nonviable oocysts. Of the 18 water supply samples analyzed, 6 (33%) presented Giardia spp. viable and nonviable cysts and 2 (11%) presented viable and nonviable Cryptosporidium spp. oocysts. G. lamblia identification was confirmed by polymerase chain reaction (PCR) and sequencing of the β-giardin gene in the fecal and water samples found positive by FISH and FITC-conjugated MAbs. C. parvum and Cryptosporidium muris were identified, by PCR and sequencing of the small subunit of ribosomal RNA gene, in seven and one water samples, respectively. Our results confirm that this technique enables simultaneous visualization, species-specific identification, and viability determination of the organisms present in human fecal and water supply samples.     

Quantitative assessment of viable Cryptosporidium parvum load in commercial oysters (Crassostrea virginica) in the Chesapeake Bay

The epidemiological importance of increasing reports worldwide on Cryptosporidium contamination of oysters remains unknown in relation to foodborne cryptosporidiosis. Thirty market-size oysters (Crassostrea virginica), collected from each of 53 commercial harvesting sites in Chesapeake Bay, MD, were quantitatively tested in groups of six for Cryptosporidium sp. oocysts by immunofluorescent antibody (IFA). After IFA analysis, the samples were retrospectively retested for viable Cryptosporidium parvum oocysts by combined fluorescent in situ hybridization (FISH) and IFA. The mean cumulative numbers of Cryptosporidium sp. oocysts in six oysters (overall, 42.1±4.1) were significantly higher than in the numbers of viable C. parvum oocysts (overall, 28.0±2.9). Of 265 oyster groups, 221 (83.4%) contained viable C. parvum oocysts, and overall, from 10–32% (mean, 23%) of the total viable oocysts were identified in the hemolymph as distinct from gill washings. The amount of viable C. parvum oocysts was not related to oyster size or to the level of fecal coliforms at the sampling site. This study demonstrated that, although oysters are frequently contaminated with oocysts, the levels of viable oocysts may be too low to cause infection in healthy individuals. FISH assay for identification can be retrospectively applied to properly stored samples.     

Prevalence and genotyping of <Emphasis Type="Italic">Cryptosporidium</Emphasis> species from farm animals in Mongolia

The presence of Cryptosporidium oocysts in 460 animals (439 cattle, 16 kids, and 5 sheep) of Tuv-aimak Mongolian district was investigated by IFT. Cryptosporidium oocysts were found in 116 (26.4%) cattle. Out of the 116 IFT positive samples, 47 were further purified by IMS, investigated by PCR and 11 were found positive. The species and/or genotypes were determined by nested PCR-RFLP and sequence analysis of a fragment of the SSU rRNA gene. The results indicated the presence of Cryptosporidium andersoni in the sequenced samples and C. bovis in two samples as a common infection. No Cryptosporidium oocysts were found in fecal specimens collected from sheep and goats. The present work reports the first data on Cryptosporidium species in animals from Mongolia. Further studies are necessary to understand the epidemiology and transmission of Cryptosporidium in domestic animals in Mongolia.     

Herd factors influencing oocyst production of Eimeria and Cryptosporidium in Estonian dairy cattle

Cryptosporidium and Eimeria are intestinal parasites which are sensitive to the surroundings, behaviour and well-being of their host. In the present study, a range of factors related to farm management systems, environment, housing and herd characteristics were investigated with regard to alterations in oocyst excretion in cattle, using a mixed-effects model. Information and samples for three age categories were obtained from 45 Estonian dairy farms, located in 15 counties. Leaving the calf with the mother after birth reduced the risk of shedding higher levels of Cryptosporidium (OR?=?0.20) and Eimeria (OR?=?0.68) oocysts in all animals. The calves younger than 3 months kept on farms housing at least 150 animals had less risk (OR?=?0.39) of producing higher numbers of Cryptosporidium oocysts. A somewhat lower infection level was observed in 3- to 12-month-old animals housed in separate buildings (OR?=?0.64). The chance of shedding higher levels of Eimeria doubled (OR?=?2.27) in cattle older than a year in case a vacancy period was used before replacing animals in pens and tripled (OR?=?2.94) when the relative humidity exceeded 75% in the cowshed. Winter reduced the odds (OR?=?0.25) of shedding Eimeria oocysts in the oldest animals compared to the fall season. Simple changes in handling and housing of cattle may produce a positive effect on controlling coccidian infections in Estonian dairy herds.     

An outbreak of cryptosporidiosis in a collection of Stone curlews (Burhinus oedicnemus) in Dubai

We describe an outbreak of cryptosporidiosis in Stone curlews kept in a mixed-species rearing unit in Dubai. Cryptosporidium was the predominant intestinal pathogen detected, although microbiological investigations revealed a concurrent Salmonella infantis infection in two of the 29 Stone curlew chicks that died. Nineteen of 29 birds had catarrhal enteritis associated with histopathological findings of numerous Cryptosporidium developmental stages at the mucosal surface. Catarrhal enteritis was present without associated Cryptosporidium oocysts in five cases. Histology of the intestine, faecal examination by direct microscopy and antigenic detection by immunochromatography revealed the presence of Cryptosporidium spp. associated with catarrhal enteritis in intestinal sections and faeces. Clinical and histopathological outcomes of infection were severe, including disruption of intestinal epithelial integrity, the presence of numerous endogenous Cryptosporidium stages in intestinal epithelia and the excretion of large numbers of sporulated oocysts. The application of polymerase chain reaction and restriction fragment length polymorphism techniques at two 18S rRNA and one Cryptosporidium oocyst wall protein gene locus confirmed the presence of Cryptosporidium parvum DNA in faecal samples.     

Isolation and Enrichment of Cryptosporidium DNA and Verification of DNA Purity for Whole-Genome Sequencing

Whole-genome sequencing of Cryptosporidium spp. is hampered by difficulties in obtaining sufficient, highly pure genomic DNA from clinical specimens. In this study, we developed procedures for the isolation and enrichment of Cryptosporidium genomic DNA from fecal specimens and verification of DNA purity for whole-genome sequencing. The isolation and enrichment of genomic DNA were achieved by a combination of three oocyst purification steps and whole-genome amplification (WGA) of DNA from purified oocysts. Quantitative PCR (qPCR) analysis of WGA products was used as an initial quality assessment of amplified genomic DNA. The purity of WGA products was assessed by Sanger sequencing of cloned products. Next-generation sequencing tools were used in final evaluations of genome coverage and of the extent of contamination. Altogether, 24 fecal specimens of Cryptosporidium parvum, C. hominis, C. andersoni, C. ubiquitum, C. tyzzeri, and Cryptosporidium chipmunk genotype I were processed with the procedures. As expected, WGA products with low (<16.0) threshold cycle (C_T) values yielded mostly Cryptosporidium sequences in Sanger sequencing. The cloning-sequencing analysis, however, showed significant contamination in 5 WGA products (proportion of positive colonies derived from Cryptosporidium genomic DNA, ≤25%). Following this strategy, 20 WGA products from six Cryptosporidium species or genotypes with low (mostly <14.0) C_T values were submitted to whole-genome sequencing, generating sequence data covering 94.5% to 99.7% of Cryptosporidium genomes, with mostly minor contamination from bacterial, fungal, and host DNA. These results suggest that the described strategy can be used effectively for the isolation and enrichment of Cryptosporidium DNA from fecal specimens for whole-genome sequencing.     

Incidence of <Emphasis Type="Italic">Cryptosporidium andersoni</Emphasis> in diarrheal patients from southern Assam,India: a molecular approach

The distribution and public health significance of Cryptosporidium species and genotypes in humans and bovine differ across geographical areas. Cryptosporidium species causes a disease known as cryptosporidiosis in humans and animals. To characterize the prevalence of cryptosporidiosis in humans in southern Assam, India, stool samples (n?=?1119) of diarrhea patients were collected from different hospitals and from the community during the period January 2014 to July 2016. Fecal smears were examined microscopically for Cryptosporidium species using modified acid fast staining and were screened to ascertain the presence of Cryptosporidium antigen by enzyme-linked immunosorbent assay (ELISA). The genomic DNA of positive fecal samples were analyzed by nested polymerase chain reaction (PCR), which were subsequently genotyped by PCR-restriction fragment length polymorphism (RFLP), based on small subunit (SSU) 18S rRNA. It was found that the prevalence of Cryptosporidium spp. was high during the monsoon season. The average infection rate of Cryptosporidium spp. was found to be 2.4% (27/1119) microscopically. When subjected to nested PCR using amplification of the 18S rRNA gene, Cryptosporidium was found to be 8.57% (98/1119). Based on the 18S rRNA gene, two Cryptosporidium spp., namely Cryptosporidium andersoni (6.97%: 78/1119) and Cryptosporidium parvum (1.7%: 20/1119), were identified. Cryptosporidium andersoni infections were found to be of either zoonotic or anthroponotic origin. The prevalence was statistically significant (p?=?0.03, R²?=?0.042) considering age, gender, and cast.     

Detection of Cryptosporidium and Giardia in agricultural and water environments in the Qinghai area of China by IFT and PCR

Qinghai Province in northwest China is strongly influenced by agricultural activities and is an important source of food and drinking water. Here, we present findings regarding the occurrence and molecular epidemiology of Cryptosporidium and Giardia species based on a large-scale investigation of areas of Qinghai Province. The diagnosis and molecular detection of Cryptosporidium oocysts and Giardia cysts was carried out using immunofluorescence microscopy (IFT), whereas nested polymerase chain reaction (PCR) in fecal smears and water samples was used for the detection and molecular characterization of the species. In total, 561 samples (260 water samples and 301 fecal samples from animals) were collected and analyzed. Of the 260 water samples, 66 samples were Cryptosporidium-positive by IFT and 71 samples were positive by nested PCR; in addition, 39 samples were Giardia-positive by IFT and 40 samples were positive by nested PCR. Of the 301 fecal samples from animals, 98 samples were Cryptosporidium-positive by IFT and 61 samples were positive by nested PCR, whereas 52 samples were Giardia-positive by IFT and 31 samples were positive by nested PCR. We showed that the water supplies and animals investigated contained Cryptosporidium and Giardia (oo)cysts. Thus, we recommend that the Chinese Government and Chinese health authorities undertake control measures to protect the food and drinking water sources in Qinghai from these pathogenic protozoa.     

Intestinal parasites of the gopher tortoise (Gopherus polyphemus) from eight populations in Georgia

The gopher tortoise (Gopherus polyphemus), one of five tortoise species endemic in the USA, was recently classified as a candidate for federal listing as a threatened species. Fecal samples collected from 117 tortoises from eight sites in Georgia were examined for endoparasites using a combination of sedimentation and flotation. Samples from an island population were examined for parasitic oocysts and ova only by flotation, protozoan cysts by trichrome-stained direct smear, and Cryptosporidium by direct immunofluorescence assay and ProSpecT rapid assay. A total of 99 tortoises (85, range 0–100 %) was infected with pinworms (Alaeuris spp.), 47 (40, 0–86 %) with cestodes (Oochorstica sp.), 34 (41, 0–74 %) with Chapiniella spp., 2 (3, 0–33 %) with Eimeria paynei, and a single tortoise each with a capillarid and ascarid (1 %). On the island, Entamoeba was detected in one tortoise (2 %) while Cryptosporidium oocysts were detected in eight (17 %). In conclusion, at least eight species of parasites were detected including Cryptosporidium, a possible pathogen of tortoises. Interestingly, we detected spatial variation in the distribution of several parasites among populations suggesting additional work should be conducted across a gradient of tortoise densities, land use, and habitat characteristics.     

Description of fecal shedding of Cryptosporidium parvum oocysts in experimentally challenged dairy calves

The objective was to describe the probability of Cryptosporidium parvum fecal oocyst shedding at different magnitudes of exposure, the pattern of fecal shedding over time, and factors affecting fecal shedding in dairy calves. Within the first 24 h of life, 36 calves were experimentally challenged with C. parvum oocysts at one of four possible magnitudes of oral exposure (1?×?10³, 1?×?10⁴, 1?×?10⁵, and 1?×?10⁶ oocysts), and 7 control calves were sham dosed. Fecal shedding occurred in 33 (91.7 %) experimentally challenged calves and in none of the control calves. There was a difference in the log-total number of oocysts counted per gram of feces dry weight among the four exposure groups; calves with the lowest magnitude of exposure (1?×?10³ oocysts) shed less than the other three groups. At higher magnitudes of exposure, there was more variability in the range of fecal oocyst shedding. There was an inverse relationship between the log-total amount of oocysts counted per gram of feces dry weight and the number of days to the onset of fecal shedding per calf, i.e., the more time that elapsed to the onset of fecal shedding, the fewer oocysts that were shed. The pattern of fecal shedding over time for all calves shedding oocysts was curvilinear; the number of oocysts increased with time, reached a peak, and declined. Therefore, the dynamics of oocyst shedding can be influenced in part by limiting exposure among calves and delaying the onset of fecal oocyst shedding.     

Occurrence of <Emphasis Type="Italic">Cryptosporidium parvum</Emphasis> and <Emphasis Type="Italic">Giardia duodenalis</Emphasis> in healthy adult domestic ruminants

To determine the prevalence and intensity of infection of Cryptosporidium spp. and Giardia duodenalis in healthy adult domestic ruminants, faecal samples were collected from 379 cattle of between 3 and 13 years old, 446 sheep and 116 goats selected at random from 60 dairy farms and 38 and 20 herds, respectively, in Galicia (NW Spain). Cryptosporidium spp. oocysts were detected in 32 cows (8.4%), 24 sheep (5.3%) and in nine goats (7.7%) from, respectively, 48.3% of the farms and 34.2 and 30.0% of the herds. The intensity of infection in cows ranged between 25 and 5,924 oocysts per gram of faeces (OPG), whereas in sheep and goats, the number of oocysts shed ranged from 8–515 OPG and from 17–782 OPG, respectively. Parasitization by Cryptosporidium spp. was significantly higher (P < 0.05) in cows than in sheep and goats. G. duodenalis cysts were identified in 101 cows (26.6%), 86 sheep (19.2%) and 23 goats (19.8%) from, respectively, 96.6% of the farms and 92.1 and 90% of the herds. The number of cysts shed by cows ranged between 15 and 3,042 cyst per gram of faeces (CPG), whereas the intensity of infection in sheep and goats ranged from 16–3010 CPG and from 15–1845 CPG, respectively, and was significantly lower (P < 0.05) than in cows and sheep. The number of Cryptosporidium spp. oocysts isolated from sheep and goats was insufficient for successful polymerase chain reaction analysis. Nevertheless, gene sequence analysis of the hsp70 and 18SrRNA genes of Cryptosporidium revealed the presence of only C. parvum in faecal samples from cows. Genotyping studies of the β-giardin and glutamate dehydrogenase genes of G. duodenalis revealed mainly assemblage E of Giardia in cows, sheep and goat faecal samples. Assemblage B of G. duodenalis was also detected in one sheep sample. These animals should be considered as a possible source of cryptosporidiosis and giardiosis, thereby maintaining the infections on farms and in herds.     

Biological nature ofCryptosporidium sp. isolated from a cat

A small type ofCryptosporidium oocysts was isolated from a naturally infected cat and its biological nature was investigated. In cats experimentally inoculated withCryptosporidium oocysts, long-lasting shedding of the oocysts occurred after a prepatent period of 8–10 days, and a number of peaks of oocyst count appeared at intervals of several days to a few weeks, earlier in the infection course.Cryptosporidium infection in cats is likely to pass from an acute to a chronic stage. During the chronic stage, prednisolone injection into the cats gave rise to a recurrence of proliferation of the parasite along with a marked increase in the number of oocysts shed. None of the infected cats showed clinical symptoms. Infection experiments usingCryptosporidium oocysts were unsuccessful in several species of animals such as mice, rats, guinea pigs, dogs, suckling mice and mice previously injected with prednisolone or hydrocortisone.     

Prevalence and distribution of Cryptosporidium spp. in dairy cattle in Heilongjiang Province, China

Few data are available on the molecular characterization of Cryptosporidium spp. in cattle in China. In the present study, a total of 507 fecal specimens from six dairy farms in Heilongjiang Province were examined for Cryptosporidium spp. by light microscopy of concentrates from the formalin-ethyl acetate sedimentation method (for less than 2-month-old calves) or Sheather’s floatation method (more than 3-month-old dairy cattle). Twenty-seven post-weaned calves on five farms were positive for Cryptosporidium oocysts. PCR and DNA sequence analysis of the 18S rRNA, actin, and 70 kDa heat shock protein genes identified Cryptosporidium andersoni and Cryptosporidium. ryanae, with C. andersoni as the dominant species (26 out of 27). In comparison with other regions of the world, the distribution of Cryptosporidium species in the areas appears to be unique.     

The role of free-ranging,captive, and domestic birds of Western Poland in environmental contamination with <Emphasis Type="Italic">Cryptosporidium parvum</Emphasis> oocysts and <Emphasis Type="Italic">Giardia lamblia</Emphasis> cysts

As Cryptosporidium parvum and Giardia lamblia can be disseminated in the environment by avian hosts, a total of 499 fecal dropping from 308 free-ranging, 90 captive, and 101 domestic birds were tested by conventional, immunological, and molecular techniques for these human enteropathogens. Twenty-six (5.2%) tested positive for G. lamblia cysts and 19 (3.8%) for C. parvum oocysts. A bird total of 23 (7.5%) free-ranging, two (2.2%) captive, and one (0.1%) domestic tested positive for cysts, whereas 18 (5.8%) free-ranging, one (1.1%) captive, and zero livestock birds tested positive for oocysts. G. lamblia cysts and C. parvum oocysts were found significantly more frequently in fecal droppings of free-ranging aquatic birds than in birds not normally associated with water. No specimen tested positive for both pathogens simultaneously. Aquatic birds represent an important epidemiologic link in water-associated transmission cycles of Cryptosporidium and Giardia and play a significant role in environmental contamination of aquatic habitats with these anthropozoonotic pathogens.     

Prevalence and molecular identification of Cryptosporidium spp. in pigs in Henan, China

The distribution and public health significance of Cryptosporidium species/genotypes in pigs differ among geographic areas and studies. To characterize the prevalence of cryptosporidiosis in pigs in Henan, China, a total of 1,350 fecal samples from 14 farms in ten prefectures in Henan Province were examined. The overall prevalence of Cryptosporidium was 8.2% (111/1,350), with the highest infection rate (79/383 or 20.6%) in 1–2-month-old piglets and the lowest infection rates in 3–6-month-old pigs. Cryptosporidium-positive samples from 108 animals were analyzed by polymerase chain reaction (PCR)-restriction fragment length polymorphism analysis of the small subunit rRNA gene, and 35 were further analyzed by DNA sequencing of the PCR products. Two Cryptosporidium species/genotype were identified, including Cryptosporidium suis (94/108) and the Cryptosporidium pig genotype II (14/108). C. suis infection was more common in younger piglets whereas the pig genotype II was relatively common in older pigs. These findings suggest that pigs are not a major source of zoonotic Cryptosporidium in the study area.