A new genotype of Cryptosporidium from giant panda (Ailuropoda melanoleuca) in China

Identification of a novel GP60 subtype family of Cryptosporidium wrairi from capybaras (Hydrochoerus hydrochaeris) inhabiting urban areas in the state of Mato Grosso do Sul, Brazil

Capybaras (Hydrochoerus hydrochaeris) are hosts for several parasites of public health importance, including Cryptosporidium spp. Therefore, this study aimed to perform the molecular characterization of Cryptosporidium spp. in fecal samples from capybaras inhabiting urban areas. We analyzed 401 fecal samples from capybaras in two municipalities of the state of Mato Grosso do Sul, Brazil. Fecal samples were purified using centrifugal sedimentation with ethyl acetate. They were then screened for Cryptosporidium spp. by malachite green negative staining and a nested PCR protocol targeting the 18S rRNA gene. Samples positive by microscopy or PCR were examined by PCR protocols targeting the actin, HSP-70, and GP60 genes. Amplicons from all PCR protocols were subjected to genetic sequencing. Microscopic screening and 18S rRNA gene-targeted PCR identified 0.25 % (1/401) and 0.5 % (2/401) of samples, respectively, as positive for Cryptosporidium spp. The genetic sequences of the 18S rRNA, HSP-70, actin, and GP60 genes showed genetic similarity to Cryptosporidium wrairi sequences of 99.07 %, 99.69 %, 99.57 %, and 91.51 %, respectively. Genetic sequencing and phylogenetic analyses identified the novel GP60 subtype family VIIbA13 of C. wrairi. In conclusion, we report in this study a low prevalence of the novel GP60 subtype family VIIbA13 of C. wrairi in free-living capybaras from urban areas of the state of Mato Grosso do Sul, Brazil. We propose that capybaras act as a novel host for C. wrairi.

Food and Waterborne Cryptosporidiosis from a One Health Perspective: A Comprehensive Review

A sharp rise in the global population and improved lifestyles has led to questions about the quality of both food and water. Among protozoan parasites, Cryptosporidium is of great importance in this regard. Hence, Cryptosporidium's associated risk factors, its unique characteristics compared to other protozoan parasites, its zoonotic transmission, and associated economic losses in the public health and livestock sectors need to be focused on from a One Health perspective, including collaboration by experts from all three sectors. Cryptosporidium, being the fifth largest food threat, and the second largest cause of mortality in children under five years of age, is of great significance. The contamination of vegetables, fresh fruits, juices, unpasteurized raw milk, uncooked meat, and fish by Cryptosporidium oocysts occurs through infected food handlers, sewage-based contamination, agricultural effluents, infected animal manure being used as biofertilizer, etc., leading to severe foodborne outbreaks. The only Food and Drug Administration (FDA)-approved drug, Nitazoxanide (NTZ), provides inconsistent results in all groups of patients, and currently, there is no vaccine against it. The prime concerns of this review are to provide a deep insight into the Cryptosporidium's global burden, associated water- and foodborne outbreaks, and some future perspectives in an attempt to effectively manage this protozoal disease. A thorough literature search was performed to organize the most relevant, latest, and quantified data, justifying the title. The estimation of its true burden, strategies to break the transmission pathways and life cycle of Cryptosporidium, and the search for vaccine targets through genome editing technology represent some future research perspectives.

Enteric parasites Cyclospora cayetanensis and Cryptosporidium hominis in domestic and wildlife animals in Ghana

BACKGROUND

Enteric parasitic infections remain a major public health problem globally. Cryptosporidium spp., Cyclospora spp. and Giardia spp. are parasites that cause diarrhea in the general populations of both developed and developing countries. Information from molecular genetic studies on the speciation of these parasites and on the role of animals as vectors in disease transmission is lacking in Ghana. This study therefore investigated these diarrhea-causing parasites in humans, domestic rats and wildlife animals in Ghana using molecular tools.

METHODS

Fecal samples were collected from asymptomatic school children aged 9-12 years living around the Shai Hills Resource Reserve (tourist site), from wildlife (zebras, kobs, baboons, ostriches, bush rats and bush bucks) at the same site, from warthogs at the Mole National Park (tourist site) and from rats at the Madina Market (a popular vegetable market in Accra, Ghana. The 18S rRNA gene (18S rRNA) and 60-kDa glycoprotein gene (gp60) for Cryptosporidium spp., the glutamate dehydrogenase gene (gdh) for Giardia spp. and the 18S rDNA for Cyclospora spp. were analyzed in all samples by PCR and Sanger sequencing as markers of speciation and genetic diversity.

RESULTS

The parasite species identified in the fecal samples collected from humans and animals included the Cryptosporidium species C. hominis, C. muris, C. parvum, C. tyzzeri, C. meleagridis and C. andersoni; the Cyclopora species C. cayetanensis; and the Gardia species, G. lamblia and G. muris. For Cryptosporidium, the presence of the gp60 gene confirmed the finding of C. parvum (41%, 35/85 samples) and C. hominis (29%, 27/85 samples) in animal samples. Cyclospora cayetanensis was found in animal samples for the first time in Ghana. Only one human sample (5%, 1/20) but the majority of animal samples (58%, 51/88) had all three parasite species in the samples tested.

CONCLUSIONS

Based on these results of fecal sample testing for parasites, we conclude that animals and human share species of the three genera (Cryptosporidium, Cyclospora, Giardia), with the parasitic species mostly found in animals also found in human samples, and vice-versa. The presence of enteric parasites as mixed infections in asymptomatic humans and animal species indicates that they are reservoirs of infections. This is the first study to report the presence of C. cayetanensis and C. hominis in animals from Ghana. Our findings highlight the need for a detailed description of these parasites using high-throughput genetic tools to further understand these parasites and the neglected tropical diseases they cause in Ghana where such information is scanty.

Genetic diversity of Cryptosporidium spp., Encephalitozoon spp. and Enterocytozoon bieneusi in feral and captive pigeons in Central Europe

Cryptosporidium spp., Enterocytozoon bieneusi and Encephalitozoon spp. are the most common protistan parasites of vertebrates. The results show that pigeon populations in Central Europe are parasitised by different species of Cryptosporidium and genotypes of microsporidia of the genera Enterocytozoon and Encephalitozoon. A total of 634 and 306 faecal samples of captive and feral pigeons (Columba livia f. domestica) from 44 locations in the Czech Republic, Slovakia and Poland were analysed for the presence of parasites by microscopy and PCR/sequence analysis of small subunit ribosomal RNA (18S rDNA), 60 kDa glycoprotein (gp60) and internal transcribed spacer (ITS) of SSU rDNA. Phylogenetic analyses revealed the presence of C. meleagridis, C. baileyi, C. parvum, C. andersoni, C. muris, C. galli and C. ornithophilus, E. hellem genotype 1A and 2B, E. cuniculi genotype I and II and E. bieneusi genotype Peru 6, CHN-F1, D, Peru 8, Type IV, ZY37, E, CHN4, SCF2 and WR4. Captive pigeons were significantly more frequently parasitised with screened parasite than feral pigeons. Cryptosporidium meleagridis IIIa and a new subtype IIIl have been described, the oocysts of which are not infectious to immunodeficient mice, whereas chickens are susceptible. This investigation demonstrates that pigeons can be hosts to numerous species, genotypes and subtypes of the studied parasites. Consequently, they represent a potential source of infection for both livestock and humans.

Taxonomy and molecular epidemiology of Cryptosporidium and Giardia - a 50 year perspective (1971-2021)

The protozoan parasites Cryptosporidium and Giardia are significant causes of diarrhoea worldwide and are responsible for numerous waterborne and foodborne outbreaks of diseases. Over the last 50 years, the development of improved detection and typing tools has facilitated the expanding range of named species. Currently at least 44 Cryptosporidium spp. and >120 genotypes, and nine Giardia spp., are recognised. Many of these Cryptosporidium genotypes will likely be described as species in the future. The phylogenetic placement of Cryptosporidium at the genus level is still unclear and further research is required to better understand its evolutionary origins. Zoonotic transmission has long been known to play an important role in the epidemiology of cryptosporidiosis and giardiasis, and the development and application of next generation sequencing tools is providing evidence for this. Comparative whole genome sequencing is also providing key information on the genetic mechanisms for host specificity and human infectivity, and will enable One Health management of these zoonotic parasites in the future.

Review on parasites of wild and captive giant pandas (Ailuropoda melanoleuca): Diversity, disease and conservation impact

The giant panda (Ailuropoda melanoleuca) is a rare species with a small global population size, and lives in the wild in only a few fragmented mountain ranges of Southwest China. Parasitic infections are among the important causes of death of giant pandas that hamper their group development. We reviewed the parasitic infections prevailing in giant pandas, and the parasitic diversity, diseases and their impact on conservation of this animal. A total of 35 parasitic species were documented in giant pandas, belonging to nematode (n = 6), trematode (n = 1), cestode (n = 2), protozoa (n = 9), and ectozoa (n = 17 (tick = 13, mite = 2, and flea = 2)). Among them, Baylisascaris schroederi had the highest prevalence and was the leading cause of death for giant pandas. Some parasites caused asymptomatic infections in giant pandas, and their health implications for the pandas remain unknown. As a whole, parasites are reported to be an important threat to the conservation of the giant pandas. Regular deworming and environmental disinfection appear to be effective ways to prevent captive giant pandas from parasitoses. In wild panda populations, parasitic control measures are suggested to include detailed examination of the ecology of the host-parasite assembly, with particular attention to density-dependent transmission. The parasitic pathogenesis and detection methods together with their biology, epidemiology, treatment, prevention and control need to be further studied for better protection of giant pandas from parasitoses.

Cryptosporidium parvum and Cryptosporidium hominis subtypes in crab-eating macaques

BACKGROUND

Non-human primates are often infected with human-pathogenic Cryptosporidium hominis subtypes, but rarely with Cryptosporidium parvum. In this study, 1452 fecal specimens were collected from farmed crab-eating macaques (Macaca fascicularis) in Hainan, China during the period April 2016 to January 2018. These specimens were analyzed for Cryptosporidium species and subtypes by using PCR and sequence analysis of the 18S rRNA and 60 kDa glycoprotein (gp60) genes, respectively.

RESULTS

Altogether, Cryptosporidium was detected using 18S rRNA-based PCR in 132 (9.1%) sampled animals, with significantly higher prevalence in females (12.5% or 75/599 versus 6.1% or 43/706), younger animals (10.7% or 118/1102 in monkeys 1-3-years-old versus 4.0% or 14/350 in those over 3-years-old) and animals with diarrhea (12.6% or 46/365 versus 7.9% or 86/1087). Four Cryptosporidium species were identified, namely C. hominis, C. parvum, Cryptosporidium muris and Cryptosporidium ubiquitum in 86, 30, 15 and 1 animal, respectively. The identified C. parvum, C. hominis and C. ubiquitum were further subtyped by using gp60 PCR. Among them, C. parvum belonged to subtypes in two known subtype families, namely IIoA14G1 (in 18 animals) and IIdA19G1 (in 2 animals). In contrast, C. hominis mostly belonged to two new subtype families Im and In, which are genetically related to Ia and Id, respectively. The C. hominis subtypes identified included ImA18 (in 38 animals), InA14 (in six animals), InA26 (in six animals), InA17 (in one animal) and IiA17 (in three animals). The C. ubiquitum isolates belonged to subtype family XIId. By subtype, ImA18 and IIoA14G1 were detected in animals with diarrhea whereas the remaining ones were mostly found in asymptomatic animals. Compared with C. parvum and C. muris, higher oocyst shedding intensity was observed in animals infected with C. hominis, especially those infected with the Im subtype family.

CONCLUSIONS

Data from the study suggest that crab-eating macaques are infected with diverse C. parvum and C. hominis subtypes. The C. parvum IIo subtype family previously seen in rodents in China has apparently expanded its host range.

Cryptosporidium proventriculi sp. n. (Apicomplexa: Cryptosporidiidae) in Psittaciformes birds

Cryptosporidiosis is a common parasitic infection in birds that is caused by more than 25 Cryptosporidium species and genotypes. Many of the genotypes that cause avian cryptosporidiosis are poorly characterized. The genetic and biological characteristics of avian genotype III are described here and these data support the establishment of a new species, Cryptosporidium proventriculi. Faecal samples from the orders Passeriformes and Psittaciformes were screened for the presence of Cryptosporidium by microscopy and sequencing, and infections were detected in 10 of 98 Passeriformes and in 27 of 402 Psittaciformes. Cryptosporidium baileyi was detected in both orders. Cryptosporidium galli and avian genotype I were found in Passeriformes, and C. avium and C. proventriculi were found in Psittaciformes. Cryptosporidium proventriculi was infectious for cockatiels under experimental conditions, with a prepatent period of six days post-infection (DPI), but not for budgerigars, chickens or SCID mice. Experimentally infected cockatiels shed oocysts more than 30 DPI, with an infection intensity ranging from 4,000 to 60,000 oocysts per gram (OPG). Naturally infected cockatiels shed oocysts with an infection intensity ranging from 2,000 to 30,000 OPG. Cryptosporidium proventriculi infects the proventriculus and ventriculus, and oocysts measure 7.4 × 5.8 μm. None of the birds infected C. proventriculi developed clinical signs.

Parasites of the Giant Panda: A Risk Factor in the Conservation of a Species

The giant panda, with an estimated population size of 2239 in the world (in 2015), is a global symbol of wildlife conservation that is threatened by habitat loss, poor reproduction and limited resistance to some infectious diseases. Of these factors, some diseases caused by parasites are considered as the foremost threat to its conservation. However, there is surprisingly little published information on the parasites of the giant panda, most of which has been disseminated in the Chinese literature. Herein, we review all peer-reviewed publications (in English or Chinese language) and governmental documents for information on parasites of the giant pandas, with an emphasis on the intestinal nematode Baylisascaris schroederi (McIntosh, 1939) as it dominates published literature. The purpose of this chapter is to: (i) review the parasites recorded in the giant panda and describe what is known about their biology; (ii) discuss key aspects of the pathogenesis, diagnosis, treatment and control of key parasites that are reported to cause clinical problems and (iii) conclude by making some suggestions for future research. This chapter shows that we are only just 'scratching the surface' when it comes to parasites and parasitological research of the giant panda. Clearly, there needs to be a concerted research effort to support the conservation of this iconic species.

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.

Ancylostoma ailuropodae n. sp. (Nematoda: Ancylostomatidae), a new hookworm parasite isolated from wild giant pandas in Southwest China

BACKGROUND

Hookworms belonging to the genus Ancylostoma (Dubini, 1843) cause ancylostomiasis, a disease of considerable concern in humans and domestic and wild animals. Molecular and epidemiological data support evidence for the zoonotic potential among species of Ancylostoma where transmission to humans is facilitated by rapid urbanization and increased human-wildlife interactions. It is important to assess and describe these potential zoonotic parasite species in wildlife, especially in hosts that have physiological similarities to humans and share their habitat. Moreover, defining species diversity within parasite groups that can circulate among free-ranging host species and humans also provides a pathway to understanding the distribution of infection and disease. In this study, we describe a previously unrecognized species of hookworm in the genus Ancylostoma in the giant panda, including criteria for morphological and molecular characterization.

METHODS

The hookworm specimens were obtained from a wild giant panda that died in the Fengtongzai Natural Reserve in Sichuan Province of China in November 2013. They were microscopically examined and then genetically analyzed by sequencing the nuclear internal transcribed spacer (ITS, ITS1-5.8S-ITS2) and mitochondrial cytochrome c oxidase subunit 1 (cox1) genes in two representative specimens (one female and one male, FTZ1 and FTZ2, respectively).

RESULTS

Ancylostoma ailuropodae n. sp. is proposed for these hookworms. Morphologically the hookworm specimens differ from other congeneric species primarily based on the structure of the buccal capsule in males and females, characterized by 2 pairs of ventrolateral and 2 pairs of dorsolateral teeth; males differ in the structure and shape of the copulatory bursa, where the dorsal ray possesses 2 digitations. Pairwise nuclear and mitochondrial DNA comparisons, genetic distance analysis, and phylogenetic data strongly indicate that A. ailuropodae from giant pandas is a separate species which shared a most recent common ancestor with A. ceylanicum Looss, 1911 in the genus Ancylostoma (family Ancylostomatidae).

CONCLUSION

Ancylostoma ailuropodae n. sp. is the fourth species of hookworm described from the Ursidae and the fifteenth species assigned to the genus Ancylostoma. A sister-species association with A. ceylanicum and phylogenetic distinctiveness from the monophyletic Uncinaria Frölich, 1789 among ursids and other carnivorans indicate a history of host colonization in the evolutionary radiation among ancylostomatid hookworms. Further, phylogenetic relationships among bears and a history of ecological and geographical isolation for giant pandas may be consistent with two independent events of host colonization in the diversification of Ancylostoma among ursid hosts. A history for host colonization within this assemblage and the relationship for A. ailuropodae n. sp. demonstrate the potential of this species as a zoonotic parasite and as a possible threat to human health. The cumulative morphological, molecular and phylogenetic data presented for A. ailuropodae n. sp. provides a better understanding of the taxonomy, diagnostics and evolutionary biology of the hookworms.

Cryptosporidium avium n. sp. (Apicomplexa: Cryptosporidiidae) in birds

The morphological, biological, and molecular characteristics of Cryptosporidium avian genotype V are described, and the species name Cryptosporidium avium is proposed to reflect its specificity for birds under natural and experimental conditions. Oocysts of C. avium measured 5.30-6.90 μm (mean = 6.26 μm) × 4.30-5.50 μm (mean = 4.86 μm) with a length to width ratio of 1.29 (1.14-1.47). Oocysts of C. avium obtained from four naturally infected red-crowned parakeets (Cyanoramphus novaezealandiae) were infectious for 6-month-old budgerigars (Melopsittacus undulatus) and hens (Gallus gallus f. domestica). The prepatent periods in both susceptible bird species was 11 days postinfection (DPI). The infection intensity of C. avium in budgerigars and hens was low, with a maximum intensity of 5000 oocysts per gram of feces. Oocysts of C. avium were microscopically detected at only 12-16 DPI in hens and 12 DPI in budgerigars, while PCR analyses revealed the presence of specific DNA in fecal samples from 11 to 30 DPI (the conclusion of the experiment). Cryptosporidium avium was not infectious for 8-week-old SCID and BALB/c mice (Mus musculus). Naturally or experimentally infected birds showed no clinical signs of cryptosporidiosis, and no pathology was detected. Developmental stages of C. avium were detected in the ileum and cecum using scanning electron microscopy. Phylogenetic analyses based on small subunit rRNA, actin, and heat shock protein 70 gene sequences revealed that C. avium is genetically distinct from previously described Cryptosporidium species.

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.

Fatal Toxoplasma gondii infection in the giant panda

Toxoplasma gondii can infect nearly all warm-blooded animals. We report an acute fatal T. gondii infection in the endangered giant panda (Ailuropoda melanoleuca) in a zoo in China, characterized by acute gastroenteritis and respiratory symptoms. T. gondii infection was confirmed by immunological and molecular methods. Multilocus nested PCR-RFLP revealed clonal type I at the SAG1 and c29-2 loci, clonal type II at the SAG2, BTUB, GRA6, c22-8, and L358 loci, and clonal type III at the alternative SAG2 and SAG3 loci, thus, a potential new genotype of T. gondii in the giant panda. Other possible pathogens were not detected. To our knowledge, this is the first report of clinical toxoplasmosis in a giant panda.

Emergence of Cryptosporidium hominis Monkey Genotype II and Novel Subtype Family Ik in the Squirrel Monkey (Saimiri sciureus) in China

A single Cryptosporidium isolate from a squirrel monkey with no clinical symptoms was obtained from a zoo in Ya'an city, China, and was genotyped by PCR amplification and DNA sequencing of the small-subunit ribosomal RNA (SSU rRNA), 70-kDa heat shock protein (HSP70), Cryptosporidium oocyst wall protein, and actin genes. This multilocus genetic characterization determined that the isolate was Cryptosporidium hominis, but carried 2, 10, and 6 nucleotide differences in the SSU rRNA, HSP70, and actin loci, respectively, which is comparable to the variations at these loci between C. hominis and the previously reported monkey genotype (2, 3, and 3 nucleotide differences). Phylogenetic studies, based on neighbor-joining and maximum likelihood methods, showed that the isolate identified in the current study had a distinctly discordant taxonomic status, distinct from known C. hominis and also from the monkey genotype, with respect to the three loci. Restriction fragment length polymorphisms of the SSU rRNA gene obtained from this study were similar to those of known C. hominis but clearly differentiated from the monkey genotype. Further subtyping was performed by sequence analysis of the gene encoding the 60-kDa glycoprotein (gp60). Maximum homology of only 88.3% to C. hominis subtype IdA10G4 was observed for the current isolate, and phylogenetic analysis demonstrated that this particular isolate belonged to a novel C. hominis subtype family, IkA7G4. This study is the first to report C. hominis infection in the squirrel monkey and, based on the observed genetic characteristics, confirms a new C. hominis genotype, monkey genotype II. Thus, these results provide novel insights into genotypic variation in C. hominis.

Prevalence and molecular characterization of Cryptosporidium in giant panda (Ailuropoda melanoleuca) in Sichuan province, China

Background

Cryptosporidium spp. have been extensively reported to cause significant diarrheal disease in humans and domestic animals. On the contrary, little information is available on the prevalence and characterization of Cryptosporidium in wild animals in China, especially in giant pandas. The aim of the present study was to detect Cryptosporidium infections and identify Cryptosporidium species at the molecular level in both captive and wild giant pandas in Sichuan province, China.

Findings

Using a PCR approach, we amplified and sequenced the 18S rRNA gene from 322 giant pandas fecal samples (122 from 122 captive individuals and 200 collected from four habitats) in Sichuan province, China. The Cryptosporidium species/genotypes were identified via a BLAST comparison against published Cryptosporidium sequences available in GenBank followed by phylogenetic analysis. The results revealed that both captive and wild giant pandas were infected with a single Cryptosporidium species, C. andersoni, at a prevalence of 15.6 % (19/122) and 0.5 % (1/200) in captive and wild giant pandas, respectively.

Conclusions

The present study revealed the existence of C. andersoni in both captive and wild giant panda fecal samples for the first time, and also provided useful fundamental data for further research on the molecular epidemiology and control of Cryptosporidium infection in giant pandas.

First report of Enterocytozoon bieneusi from giant pandas (Ailuropoda melanoleuca) and red pandas (Ailurus fulgens) in China

Enterocytozoon bieneusi is an emerging and opportunistic enteric pathogen triggering diarrhea and enteric disease in humans and animals. Despite extensive research on this pathogen, the prevalence and genotypes of E. bieneusi infection in precious wild animals of giant and red pandas have not been reported. In the present study, 82 faecal specimens were collected from 46 giant pandas (Ailuropoda melanoleuca) and 36 red pandas (Ailurus fulgens) in the northwest of China. By PCR and sequencing of the internal transcribed spacer (ITS) region of the ribosomal RNA (rRNA) gene of E. bieneusi, an overall infection rate of 10.98% (9/82) was observed in pandas, with 8.70% (4/46) for giant pandas, and 13.89% (5/36) for red pandas. Two ITS genotypes were identified: the novel genotype I-like (n=4) and genotype EbpC (n=5). Multilocus sequence typing (MLST) employing three microsatellites (MS1, MS3 and MS7) and one minisatellite (MS4) showed that nine, six, six and nine positive products were amplified and sequenced successfully at four respective loci. A phylogenetic analysis based on a neighbor-joining tree of the ITS gene sequences of E. bieneusi indicated that the genotype EbpC fell into 1d of group 1 of zoonotic potential, and the novel genotype I-like was clustered into group 2. The present study firstly indicated the presence of E. bieneusi in giant and red pandas, and these results suggested that integrated strategies should be implemented to effectively protect pandas and humans from infecting E. bieneusi in China.

Natural infection of Cryptosporidium muris in ostriches (Struthio camelus)

A total of 303 fecal samples were collected from ostriches (Struthio camelus) and 31 samples (10.2%) were Cryptosporidium-positive upon microscopic analysis. The infection rate was 27.6% in ostriches aged 16-60 days, 1.2% in those aged 61-180 days, and 20.4% in those aged >10 years. The Cryptosporidium-positive isolates were genotyped with a restriction fragment length polymorphism analysis and DNA sequence analysis of the small subunit (SSU) rRNA gene. The 22 isolates from ostriches aged >10 years were identified as Cryptosporidium muris, whereas the nine isolates from ostriches <180 days were Cryptosporidium baileyi. Ten of the 22 C. muris isolates were analyzed based on the actin and HSP70 genes, and the results were identical to those observed for the SSU rRNA gene. Cross-transmission studies demonstrated that the C. muris isolate infected BALB/c mice and Mongolian gerbils, but did not infect chickens. C. muris isolated in this study appears to be host-adapted, consistent with a previous multilocus sequence typing analysis. Further studies are required to understand the prevalence and transmission of Cryptosporidium spp. in ostriches in different geographic areas.

Multilocus genotype and subtype analysis of Cryptosporidium andersoni derived from a Bactrian camel (Camelus bactrianus) in China

Fecal specimens from two Bactrian camels were collected in the Ya'an city zoo of China and were examined for Cryptosporidium by centrifugal flotation. One specimen was found to be parasitized by Cryptosporidium via microscopy, and the oocysts were measured to have an average size of 7.03 × 5.50 μm (n > 50). The isolate was genotyped by polymerase chain reaction (PCR) amplification and DNA sequence analysis of the partial 18S rRNA, COWP, and A135 genes, and was confirmed to be Cryptosporidium andersoni with minor nucleotide differences. Multilocus sequence typing (MLST) analysis indicated that the subtype of the camel-derived C. andersoni isolate was A4, A4, A4, and A1 at the four minisatellite loci (MS1, MS2, MS3, and MS16, respectively). Therefore, this isolate belongs to the most common MLST subtype reported in cattle in China and is distinct from two other known camel C. andersoni MLST subtypes (A6, A4, A2, A1 and A6, A5, A2, A1). Animal transmission experiments demonstrated that the C. andersoni isolate was not infectious to immunosuppressed or immunocompetent Kun-ming mice, Sprague-Dawley rats, and hamsters but was biologically similar to most bovine C. andersoni isolates characterized so far. Therefore, transmission of this camel-derived C. andersoni isolate is very likely to occur between camels and bovine.