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Molecular characterization and zoonotic potential of Cryptosporidium spp. and Giardia duodenalis in humans and domestic animals in Heilongjiang Province, China

Abstract

Background

Cryptosporidiosis and giardiasis are significant parasitic diseases shared between humans and domestic animals. Due to the close contact between humans and domestic animals in rural areas, it is important to consider the potential transmission of zoonotic parasites from infected domestic animals to humans. This investigation aimed to determine the prevalence and molecular characteristics of Cryptosporidium spp. and Giardia duodenalis in domestic animals and villagers.

Methods

A total of 116 fecal samples from villagers and 686 fecal samples from domestic animals in Heilongjiang Province, China, were analyzed for two parasites using nested polymerase chain reaction (PCR) targeting various genetic loci and DNA sequence analysis of the PCR products.

Results

By sequence analysis of the SSU rRNA gene, the prevalence of Cryptosporidium in humans was 0.9% (1/116), with one species of C. parvum (n = 1) detected; among domestic animals, the prevalence was 2.6% (18/686), with five species identified: C. suis (n = 7) and C. scrofarum (n = 7) in pigs, C. meleagridis (n = 1) in chickens, C. andersoni (n = 1) in cattle, and C. canis (n = 2) in foxes. C. parvum and C. canis were further subtyped as IIdA19G1 and XXa4 on the basis of gp60 gene. Regarding G. duodenalis, based on the SSU rRNA, bg, gdh, and tpi genes, the prevalence in domestic animals was 5.1% (31/608), with three assemblages identified: A (n = 1) in pigs, D (n = 1) in foxes, and E (n = 27) in geese, cattle, pigs, ducks, and sheep, along with mixed infection of A + E (n = 1) in one pig and B + E (n = 1) in one sheep. No G. duodenalis was detected in humans (0/116).

Conclusions

The present results show that no overlap of subtypes between animals and villagers was found in Cryptosporidium spp. and G. duodenalis, indicating a minor role of domestic animals in infecting humans in this population. However, the presence of zoonotic protozoa in domestic animals highlights the need for special attention to high-risk individuals during close contact with domestic animals.

Graphical Abstract

Background

Cryptosporidium spp. and Giardia duodenalis (G. duodenalis, also known as G. lamblia or G. intestinalis) are important protozoan parasites with primary clinical symptoms of diarrhea. These parasites are widespread and can infect humans, domestic animals, and wild animals. The cysts/oocysts of both parasites are shed in the feces of infected hosts and can be transmitted to new hosts via contaminated food, water, or direct contact with infected humans or animals [1, 2]. Both protozoa have a monoxenous life cycle, a low infective dose, and a short prepatent period, which increase their potential for transmission in human and animal hosts [3]. Some families keep domestic animals in their yards and share public places with them, increasing the potential for zoonotic transmission [2].

The oocysts of many Cryptosporidium species are difficult to distinguish from one another, as they share similar morphological characteristics. Therefore, molecular methods are essential for identifying Cryptosporidium species, genotypes, and subtypes that can identify organisms and trace the infection source and transmission routes [4]. Targeting the small subunit of ribosomal RNA (SSU rRNA) is a useful tool for Cryptosporidium species identification [5]. To date, extensive genetic variation has been identified within the Cryptosporidium, with at least 49 valid Cryptosporidium species and more than 120 genotypes being recognized [1, 6]. Among them, 23 species and two genotypes have been identified in humans, and C. hominis and C. parvum are the most common species, accounting for 95% of human cases [1, 7, 8]. In addition, with the development of whole-genome sequencing, a gene encoding 60-kDa glycoprotein (gp60) has been employed as a marker to subtype 23 Cryptosporidium species and two genotypes [9]. Similarly, genotyping of G. duodenalis is crucial for epidemiological studies, which are mainly performed using sequence analysis of polymerase chain reaction (PCR) products from genes, such as SSU rRNA gene, β-giardin (bg), glutamate dehydrogenase (gdh), and triosephosphate isomerase (tpi) [10]. Using multiple markers ensures more reliable genotyping results and helps detect mixed infections with different assemblages in humans or animals [11]. G. duodenalis is classified into eight assemblages (A–H) based on protein or DNA polymorphisms, and assemblages A and B are considered zoonotic, which primarily cause infections in humans and mammals. The other six assemblages (C–H) are host specific, however, assemblages C–F are also occasionally identified in humans [1]. Only assemblage A can be further divided into three sub-assemblages (AI, AII, and AIII), while no recognized nomenclature exists for assemblages B–H [10].

The potential transmission of these two parasites among humans and animals living in close proximity has been sparsely reported. In Côte d’Ivoire, the occurrence of Cryptosporidium and G. duodenalis in humans and free-ranging animals living in remote rural zones provided evidence about the potential role of these domestic animals living closely with humans in the environmental dissemination and transmission of these anthropozoonotic parasites to humans [12]. Conversely, in Western Uganda, no evidence of potential transmission of Cryptosporidium and G. duodenalis was found among closely cohabiting people, domestic animals, and wild nonhuman primates [13]. Meanwhile, in Álava, northern Spain, no molecular epidemiological evidence supported household transmission of zoonotic Cryptosporidium and G. duodenalis from pet dogs and cats [14]. On the basis of the studies in different regions, it can be concluded that the occurrence and potential transmission of Cryptosporidium and G. duodenalis can vary depending on the specific geographical location and the interactions between humans and animals.

In China, there are also few data available for molecular epidemiological studies on both parasites in humans and domestic animals coexisting in the same habitat. In Heilongjiang Province, domestic animals such as cattle, goats, sheep, pigs, chickens, and other species are raised in an agricultural setting to produce various commodities—usually food (meat, organs, eggs, dairy products), as well as hair or wool [15]. Due to the close contact between humans and domestic animals, there are concerns about the potential transmission of the zoonotic species/assemblages of these two parasites from infected domestic animals to humans. The aim of the study was to determine the prevalence and distribution of species, genotypes, and subtypes of Cryptosporidium and G. duodenali assemblages and sub-assemblages in humans and domestic animals and understand the role of animals in the environmental dissemination of zoonotic Cryptosporidium and G. duodenalis.

Methods

Sources and collections of fecal samples

From November 2020 to December 2022, a total of 802 fecal samples (approximately 5–10 g) were collected from humans and animals (one sample from each) from nine villages in Heilongjiang Province, China (Fig. 1, Table 1). For families with domestic mammals and poultry, the participants were randomly selected to provide individual fecal samples including animals. A total of 68 households were included. Among these households, 5 only provided fecal samples of animal origin, and 20 households only provided samples of human origin. None of the humans and domestic animals had any apparent clinical symptoms of diarrhea at the time of sampling. Each fecal sample was collected from the upper portion of fresh feces deposited on the ground after defecation by using disposable gloves and placed into 50 ml sterile containers individually. All the samples were transported to the laboratory in a cooler with ice packs within 24 h and stored in refrigerators at 4 ℃ (≤ 2 days) or −20 ℃ (> 2 days) prior to using in the subsequent molecular analysis.

Fig. 1
figure 1

Sampling sites for enteric protist samples from villagers and domestic animals in Heilongjiang Province, China

Table 1 Fecal sample collection details from humans and domestic animals in nine villages, Heilongjiang Province, China

Processing of fecal samples and DNA extraction

The fecal samples of herbivores needed to be processed by sieving the crude fiber and impurities in the samples and concentrating for 10 min at 1500 g. Meanwhile, the fecal samples of the other animals and humans were simply washed twice with distilled water by centrifugation to concentrate the samples. Then, genomic DNA (gDNA) was extracted from approximately 200 mg of processed fecal samples using the QIAamp DNA Mini Stool Kit (Qiagen, Hilden, Germany), following the manufacturer’s recommended procedure. The extracted DNA was then stored at −20 °C until it was used for PCR amplification.

PCR amplification

Cryptosporidium was detected by nested PCR amplification of the SSU rRNA gene fragment of 830 base pairs (bp) [16]. Further, C. parvum-, C. meleagridis-, and C. canis-positive samples were subtyped by nested PCR amplification of the gp60 gene. Different subtyping tools based on gp60 gene were utilized for subtyping three Cryptosporidium species [17,18,19].

The assemblages and sub-assemblages of G. duodenalis were identified by a nested PCR to amplify the SSU rRNA (290 bp) [20], bg (511 bp) [21], gdh (530 bp) [22], and tpi (530 bp) genes [23]. In addition, to detect mixed infections of different G. duodenalis assemblages within the same sample, specific nested PCRs were performed to amplify the tpi gene with fragment sizes of approximately 330 bp (assemblage A), 400 bp (assemblage B), and 390 bp (assemblage E) [24, 25].

TaKaRa Taq DNA polymerase (TaKaRa Bio Inc., Tokyo, Japan) was utilized for all PCR amplification. Each PCR analysis included positive and negative controls, and each sample was subjected to at least two PCR analyses at each genetic site. All secondary PCR products were separated by 1.5% agarose gel electrophoresis stained with GelStain (TransGen Biotech., Beijing, China).

DNA sequencing and nucleotide sequence analysis

All positive secondary PCR products of the expected size were subjected to sequencing using the secondary PCR primers on an ABI PRISMTM 3730 DNA analyzer (Applied Biosystems, Waltham, MA, USA) with the BigDye Terminator v3.1Cycle Sequencing Kit (Applied Biosystems). The accuracy of the nucleotide sequence was confirmed by two-directional sequencing. If novel nucleotide sequences were obtained from certain DNA samples, two additional new PCR products were sequenced as necessary. Nucleotide sequences obtained in the present study were aligned and analyzed with each other and reference sequences that were downloaded from GenBank using the Basic Local Alignment Search Tool (BLAST) (http://www.ncbi. nlm.nih.gov/blast/). Generated DNA consensus sequences were aligned to appropriate reference sequences using the MEGA 5 software (http://www.megasoftware.net) to identify the species/subtypes of Cryptosporidium and the assemblages/sub-assemblages of G. duodenalis.

The representative nucleotide sequences obtained in the present study were deposited in the GenBank database under the following accession numbers: human-derived Cryptosporidium isolates—OR357663 (SSU rRNA) and OR353407 (gp60); animal-derived Cryptosporidium isolates—OR357660 to OR357662, OR357664 to OR357666 (SSU rRNA), and OR353406 (gp60); animal-derived G. duodenalis isolates—OR359371 to OR359372 (SSU rRNA), OR353408 to OR353412 (bg), OR360610 to OR360618 (gdh), and OR353413 to OR353416 (tpi).

Phylogenetic analysis

The phylogenetic tree was constructed on the basis of the neighbor-joining (NJ) method and the Kimura-2-parameter model using the program MEGA 5. To assess the tree’s reliability, a bootstrap analysis with 1000 replicates was performed. Reference sequences from GenBank were downloaded, and the sequences were labeled with National Center for Biotechnology Information (NCBI) accession number, the host origin, and the country.

Results

Prevalence of Cryptosporidium spp. and G. duodenalis

Using PCR amplification and sequence analysis, Cryptosporidium was found in humans and domestic animals, while G. duodenalis was only found in some domestic animals. The prevalence of Cryptosporidium was 0.9% (1/116) in humans, whereas the overall prevalence was 2.6% (18/686) in domestic animals, with 5.0% (17/340) in domestic mammals, including cattle (2.0%, 1/51), foxes (4.3%, 2/46), and pigs (8.8%, 14/160), with 0.3% (1/346) in poultry, including chickens (0.4%, 1/253). Meanwhile, Cryptosporidium was absent in dogs, goats, raccoon dogs, rabbits, sheep, ducks, and geese (Table 2). For G. duodenalis, in domestic animals the overall prevalence was 4.5% (31/686). The prevalence was 8.2% (28/340) in domestic mammals, including cattle (9.8%, 5/51), foxes (2.2%, 1/46), pigs (3.1%, 5/160), and sheep (28.8%, 17/59), and the prevalence was 0.9% (3/346) in poultry, including ducks (10.0%, 1/10) and geese (2.4%, 2/83) (Table 2). Meanwhile, G. duodenalis was absent in humans and domestic animals (dogs, goats, raccoon dogs, rabbits, and chickens).

Table 2 Prevalence and distribution of Cryptosporidium species/subtypes and G. duodenalis assemblages/sub-assemblages in humans and domestic animals

Molecular characteristics of Cryptosporidium spp. isolates

On the basis of sequence analysis of the SSU rRNA gene, a total of six species/genotypes of Cryptosporidium were identified out of 19 isolates, including C. parvum (n = 1) in humans, C. suis (n = 7) and C. scrofarum (n = 7) in pigs, C. meleagridis (n = 1) in chickens, C. andersoni (n = 1) in cattle, and C. canis (n = 2) in foxes (Table 2). The sequences of the SSU rRNA gene for the C. parvum, C. suis, C. meleagridis, C. andersoni, and C. canis in this study are 100% identical to reference sequence deposited in GenBank. Among the seven C. scrofarum isolates from pigs, six showed complete sequence identity with a sequence (MG576147) from a pig in India. One isolate showed 98.9% similarity to C. scrofarum (MH174663) obtained from a Tibetan pig in Henan, China, with a single base difference (C528T) (Additional file 1: Table S1). Phylogenetic analysis of SSU rRNA nucleotide sequences confirmed the observations made during the sequencing analysis (Fig. 2).

Fig. 2
figure 2

The phylogram of Cryptosporidium spp. was inferred on the basis of the SSU rRNA gene nucleotide sequences. The evolutionary relationship of Cryptosporidium spp. was constructed by the NJ method and Kimura 2-parameter model. The numbers on the branches are percent bootstrapping values from 1000 replicates. Each reference sequence is identified by its accession number, host, and country. The triangles filled in black represent the representative sequence obtained in this study. Evolutionary analyses were conducted in MEGA 5

For subtyping of the Cryptosporidium species, DNA samples characterized as originating from C. parvum, C. meleagridis, and C. canis were further subjected to sequence analysis of the gp60 gene. One C. parvum isolate was successfully sequenced and identified as subtype IIdA19G1. In addition, two C. canis isolates were successfully sequenced and both were identified as subtype XXa4. Phylogenetic analysis of the gp60 nucleotide sequences revealed that C. canis subtype XXa4 sequences obtained from two foxes in this study, as well as sequences from human, raccoon dog, and dog downloaded from GenBank, were clustered together into one clade with high bootstrap value (Fig. 3).

Fig. 3
figure 3

The phylogram of Cryptosporidium spp. was inferred on the basis of the nucleotide sequences of the gp60 gene. The evolutionary relationship of Cryptosporidium spp. was constructed by the NJ method and Kimura 2-parameter model. The numbers on the branches are percent bootstrapping values from 1000 replicates. Each reference sequence is identified by its accession number, host, and country. The circle filled in black represents the representative sequence obtained in this study. Evolutionary analyses were conducted in MEGA 5

Molecular characteristics of G. duodenalis isolates

There are 31 G. duodenalis-positive samples based on four loci, and 22 SSU rRNA, 9 bg, 12 gdh, and 6 tpi gene sequences were obtained. Only one positive sample was successfully sequenced at all four loci, whereas the remaining samples were amplified at one to three loci (Additional file 2: Table S2). Sequence analysis results showed that assemblage A (n = 1) was identified in one pig, assemblage D (n = 1) in one fox, and assemblage E (n = 27) in pigs, cattle, sheep, ducks, and geese. Additionally, mixed infections were identified in one pig (A + E) and one sheep (B + E) (Additional file 2: Table S2).

The genetic diversity of G. duodenalis among assemblages E, D, and A was observed at the bg, gdh, and tpi loci. Within assemblage E, four representative sequences (E#1–E#4) having single nucleotide substitutions (SNPs) were obtained from one, two, three, and one isolates at the bg locus, respectively; six representative sequences (E#5–E#10) having SNPs were obtained from two, two, one, one, two, and one isolates at the gdh locus, respectively; and three representative sequences (E#11–E#13) with SNPs were obtained from one, two, and one isolates at the tpi locus, respectively. Within assemblage D, one representative sequence (D#1) was obtained from one isolate at the bg locus, and one representative sequence (D#2) was obtained from the same isolate at the gdh locus. Furthermore, within assemblage A, two representative sequences (AI#1 and AI#2) were obtained from two isolates at the gdh locus, both belonging to AI. Only one representative sequence (B#1) was obtained from one isolate at the tpi locus (Additional file 3: Table S3).

Distribution of species/subtype of Cryptosporidium spp. and assemblage/sub-assemblage of G. duodenalis in humans and domestic animals in households

A total of 68 family households were investigated, and regardless of the host, Cryptosporidium and/or G. duodenalis were detected in 22.1% (15/68) of these households, as presented in Table 3. In 53.3% (8/15) of the households, Cryptosporidium was detected in human or domestic animal fecal samples. Additionally, in 73.3% (11/15) of the households, G. duodenalis was identified in domestic animals. Simultaneous infections by any of these two parasites in humans and domestic animals living together in the same environment were only demonstrated in one household: in the DFH-5 family, Cryptosporidium was detected in both one cow and its owner. However, this cow was found to be infected with C. andersoni, while the owner was infected with C. parvum. Simultaneous infections by the same species/subtypes of Cryptosporidium and/or assemblage of G. duodenalis in domestic animals in the same environment were demonstrated in nine households. For Cryptosporidium, in the DFH-3 family, C. suis was identified in Cryptosporidium-positive pigs (n = 4), which was also found in pigs (n = 3) from the CF-1 family. Additionally, in the CF-1 family, C. scrofarum was identified in pigs (n = 4). In the YHA-3 family, C. canis (subtype XXa4) was identified in Cryptosporidium-positive foxes (n = 2). For G. duodenalis, assemblage E was detected in Giardia-positive sheep (n = 14) in the GA-4 family and in geese (n = 2) in the YHA-2 family. Assemblage E was also detected in cattle (n = 2) from the YH-5 family and cattle (n = 2) from the DFH-2 family, pigs (n = 2) in the DFH-9 family, and sheep (n = 2) in the YHA-7 family. One pig from the DFH-9 family was infected with Cryptosporidium and G. duodenalis (Table 3).

Table 3 Distribution of Cryptosporidium species/subtypes and G. duodenalis assemblages/sub-assemblages in humans and domestic animals by household

Discussion

The prevalence of Cryptosporidium or G. duodenalis varies in humans and animals between countries and even between regions of the same country. In the present study, the prevalence of Cryptosporidium was 0.9% in humans who lived in rural areas, which was lower than the rates reported in most previous studies. For example, in the Yi Autonomous Prefecture in southwestern China, a region with a mild climate belonging to the subtropical humid zone, the prevalence of Cryptosporidium (12.0%, 74/615) was high among the village residents [26]. Meanwhile, a higher prevalence of Cryptosporidium was also found in the general population in other countries, such as 69.6% in Mexico [27]. Furthermore, humans were not found to be infected with G. duodenalis in the present study, indicating a lower prevalence compared with previous studies, such as 6.1% in the Hui ethnic group in Qinghai Province [28] and 8.2% in rural areas of Sichuan Province [29]. Comparatively, a higher prevalence of G. duodenalis was reported in other countries, particularly in Africa, with a prevalence of 11.7% among the agricultural population in Morocco [30], 29.0% in rural districts in northern Ethiopia [31], and as high as 34.6% in people in Egypt [32]. The prevalence of the two parasites may be influenced by weather and climate conditions; low temperatures and dry climate present may reduce the chance of Cryptosporidium and G. duodenalis transmission [33, 34]. In this study, only one human-derived Cryptosporidium-positive isolate was obtained, and it was collected during the warm and rainy month of August. Therefore, the low prevalence could be attributed to the majority of samples being collected during the fall and winter seasons in northeast China.

The prevalence of Cryptosporidium and G. duodenalis exhibits significant variation in animals between and within countries worldwide. For instance, in domestic mammals, the prevalence of Cryptosporidium ranged widely, from 0.1% to 100% in pigs and from 0.0% to 100% in cattle [15]. In poultry, such as chickens, prevalence also displayed considerable variation. Prevalence had been reported to be 0.5% in Iran [35], while in Algeria, the prevalence reached as high as 34.4% [36]. In the present study, Cryptosporidium was detected in various domestic animals (pigs, cattle, foxes, and chickens) with prevalence ranging from 0.4% in chickens to 8.8% in pigs. Notably, Cryptosporidium was identified in chickens for the first time in Heilongjiang Province, with lower prevalence (0.4%) compared with other Chinese provinces. For example, prevalence in chickens from Guangdong Province was 13.2% [37], followed by Hubei Province with 10.2% [38]. For G. duodenalis, it was also detected in a variety of domestic animals (pigs, cattle, sheep, foxes, ducks, and geese), with prevalence ranging from 2.2% in foxes to 28.8% in sheep. To our knowledge, G. duodenalis was identified in foxes for the first time in China.

In this study, six Cryptosporidium species were identified, including C. parvum, C. canis, C. meleagridis, C. suis, C. scrofarum, and C. andersoni. In a phylogenetic analysis, the sequence of C. parvum obtained from a human sample in this study clustered with those from cattle (MF671870, MK426796) in one branch. Simultaneously, the sequences of C. canis, C. meleagridis, C. suis, C. scrofarum, and C. andersoni obtained from animal samples clustered with human-derived sequences KT74981, AY166839, MH187877, EU331243, and KF826313, respectively, on the corresponding branches. The findings suggest these Cryptosporidium species have a zoonotic potential, and animals may serve as a reservoir for humans infected with Cryptosporidium (Fig. 2) [39, 40].

Further, C. parvum and C. canis subtyping at the gp60 gene revealed the subtype as IIdA19G1 and XXa4, respectively. The most investigated Cryptosporidium implicated in zoonotic transmission is C. parvum, with approximately 20 subtype families identified. Among them, the IIa and IId were defined as zoonotic parasites [41]. In China, IIdA15G1 and IIdA19G1 were found to be the dominant C. parvum IId subtype in calves, and the IIdA19G1 has been reported in eight provinces, one autonomous region, and three municipalities [42,43,44,45,46,47,48,49,50], including Heilongjiang Province. Moreover, this subtype has caused outbreaks of Cryptosporidiosis in neonatal calves on one dairy farm in Jiangsu Province [48]. Meanwhile, human infections with IIdA19G1 were mostly reported in Europe, the Middle East, and New Zealand [51,52,53]. In China, it was also identified in four hospitalized children and two patients with human immunodeficiency virus (HIV) [54, 55]. These findings suggest that neonatal calves may act as a reservoir for the transmission of human Cryptosporidium infections [56]. However, in the present study, C. parvum subtype IIdA19G1 was detected in a 54-year-old non-diarrheal male participant, which is the first reported in humans in Heilongjiang Province. In contrast, this subtype was not found in the cattle of this family. On the basis of current data, it was unclear whether humans can be infected with C. parvum IIdA19G1 through cattle. Therefore, more human and domestic animal samples are needed to identify the potential animal reservoirs of human infection.

C. canis is the most frequently identified species in dogs worldwide, and it is also found in foxes, coyotes, minks, mongoose, raccoon dogs, cattle, and sheep [57, 58]. Notably, human cases of cryptosporidiosis caused by C. canis have been reported in immunocompetent humans in the USA, Ethiopia, and Peru and immunocompromised individuals in Jamaica and Peru [59, 60]. Due to the zoonotic nature of C. canis, people should be aware of the potential zoonotic transmission of cryptosporidiosis. By using the newly developed subtyping tool, C. canis has been classified into seven known subtype families (IIIa–IIIg) [18, 61]. In the present study, two C. canis isolates derived from foxes were identified as XXa4, which was the first reported worldwide. Wang et al. reported that XXa was only detected in raccoon dogs, while XXg was only in foxes, indicating the existence of host adaptation in C. canis among fur animal species [61]. Our results are inconsistent with those of previous studies, and due to the limited number of positive samples, we are unable to provide a satisfactory explanation for the host adaptation. Therefore, a substantial number of samples from foxes are needed to validate this subtype of the host adaptation. Despite no C. canis infection being detected in owners in the same households in our study, the zoonotic potential of C. canis should not be overlooked.

C. meleagridis has been detected in various avian hosts, such as pigeons, quails, chickens, turkeys, and so on [62,63,64,65]. However, it has also been identified in humans in several low- and middle-income countries, including in Africa and Asia [55, 66, 67]. To date, Cmeleagridis has ten known subtype families (IIIa–IIIi), with IIIb among the most common. Molecular studies have revealed that identical C. meleagridis subtypes were identified in humans and chickens in the same location in Sweden, suggesting cross-species transmission of C. meleagridis between birds and humans [38, 39]. In this study, C. meleagridis the species was found in a single chicken, and this isolate was not successfully subtyped. Noteworthy, chickens may act as a source of infection or a mechanical vector by shedding C. meleagridis oocysts into the environment [37].

In the present study, C. suis and/or C. scrofarum were only identified in pigs, which are the type hosts for both these species [40, 68, 69]. Moreover, studies demonstrated that C. suis and C. scrofarum could also infect humans. C. suis was identified in individuals with diarrhea in England, [70], as well as in children in Cambodia [71], and in patients infected with HIV in China, Peru, and Thailand [55, 72, 73]. Therefore, pigs in study areas could pose a potential threat to human security due to asymptomatic infection and close contact with humans. In addition, C. andersoni was found in one cow in the present study. C. andersoni mostly responsible for bovine cryptosporidiosis [64], and has also been reported to infect different animals, such as mice [74], cattle, sheep, goats [75], birds [76], cats, and dogs [10]. Human infections with C. andersoni have been detected in several countries, including the UK [70], Malawi [71], Iran [77], and China [72], while in China, a high prevalence of C. andersoni in immunocompetent children and adults has been reported [72, 78]. In the present study, C. andersoni was identified in one cow, which remains a severe threat to susceptible animals (cattle, sheep, and goats) and humans.

For G. duodenalis, assemblages A, D, and E were identified in domestic animals in our study. Additionally, two mixed infection cases were found, with A + E in one pig and B + E in one sheep. Among them, assemblage E was the most prevalent (Tab S2). Several studies have suggested that assemblage E is strongly associated with host specificity, particularly in cloven-hoofed livestock [79,80,81,82]. However, more than 50 human cases of assemblage E have been identified in recent years in Brazil, Egypt, Vietnam, Australia, and New Zealand [53, 81,82,83,84], highlighting its potential for zoonotic transmission. In this study, assemblage E was found in sheep (16/27), pigs (3/27), cattle (5/27), ducks (1/27), and geese (2/27). Despite cohabitation between humans and these domestic animals, assemblage E was not detected in humans. Assemblage E is frequently encountered in hoofed mammals and it has previously been reported in fecal droppings from brown- and black-headed gulls, geese, and cormorants [85]. In the meantime, it is reported that Giardia cysts have been identified in the feces of migratory Canada geese. These geese are known to follow cattle and consume undigested plant material found in cattle feces [86]. Hence, it is plausible that the presence of assemblage E in ducks and geese may be attributed to the contamination of their environment from cattle or sheep feces, as these animals were also found to be infected with assemblage E in the current study. Additionally, previous research also showed that the occurrence of Giardia cysts in bird feces might indicate mechanical transmission rather than established infections [12, 87].

Assemblages D is predominantly associated with dogs, foxes, coyotes, and seals [10, 88] and has also been identified in pigs and cattle [89, 90]. In rare instances, it has been reported in cats [91]. In the present study, assemblage D was only detected in a fox. Notably, assemblage D has also been reported in humans, and to date, no more than 16 cases of human giardiasis have been found in Europe, Egypt, Germany, and Thailand [11, 32, 92, 93]. These results revealed that the host-adapted assemblage D was no longer confined to specific hosts, and possessed a broader host range than previously believed.

Assemblages A and B are responsible for most giardiasis cases in humans. Assemblage B was more commonly reported in Asia, Oceania, Europe, and Africa. However, in South America and the Middle East, assemblage A is more common [1, 94,95,96]. Among farm animals, such as cattle, sheep, and goats, assemblage A has been found to have some occurrence and assemblage B occasional occurrence [1]. In the assemblages A: AI is considered zoonotic, AII is mainly found in humans, and AIII is exclusively found in animals [22]. In the present study, assemblage AI was confirmed in one pig. By sequence analysis, assemblage AI sequence compared with reference sequence download from GenBank had a single nucleotide polymorphism (SNP). However, another pig exhibited a mixed infection of assemblage AI and E, with assemblage E having a SNP. Furthermore, one sheep showed a mixed infection of assemblage E and B. However, assemblages B, D, and E were compared with corresponding reference sequences from GenBank, which revealed no SNPs.

In the present study, an overlap of subtype between animals and their owners in Cryptosporidium spp. and G. duodenalis was not found, which suggested a limited role of domestic animals in the human cryptosporidiosis or giardiasis in the studied population. Nevertheless, it is necessary to pay special attention to the zoonotic potential of these species, especially in children and immunocompromised individuals who have close contact with domestic animals.

Conclusions

The present study describes the prevalence, species, and subtypes of Cryptosporidium and assemblage and sub-assemblage of G. duodenalis in humans and domestic animals in nine villages in Heilongjiang Province. C. parvum was discovered in a human, and C. canis, C. meleagridis, C. suis, C. scrofarum, and C. andersoni were identified in domestic animals. These species are zoonotic Cryptosporidium species. However, the G. duodenalis assemblages A, B, D, and E were only found in domestic animals. Assemblages A and B are considered potentially zoonotic, while the other assemblages have also been reported in humans. The presence of these Cryptosporidium species and G. duodenalis assemblages in animals poses a potential risk to human health, especially in areas where humans have close contact with infected animals. Therefore, public education programs should be implemented to raise awareness among villagers regarding the potential transmission of parasites from domestic animals and the importance of hygiene in disease prevention.

Furthermore, it is recommended that veterinarians and physicians should implement effective control measures to reduce the burden of these two parasitic diseases. Their involvement will contribute to enhancing the overall health and well-being of the rural community in their coexistence with domestic animals.

Availability of data and materials

All data generated or analyzed during this study are included in this published article. The nucleotide sequences have been deposited in GenBank database under the accession numbers: OR357660 to OR357666 and OR353406 to OR353407 (Cryptosporidium); OR359371 to OR359372, OR353408 to OR353416, and OR360610 to OR360618 (G. duodenalis).

Abbreviations

CF:

Changfa village

DFH:

Dongfanghong village

GA:

Gongan village

QJ:

Qianjin village

SF:

Shuangfa village

XL:

Xinglong village

XF:

Xianfeng village

YH:

Yuhe village

YHA:

Youhao village

SSU rRNA:

Small subunit ribosomal ribonucleic acid

NJ:

Neighbor-joining

PCR:

Polymerase chain reaction

bp:

Base pair

SNPs:

Single nucleotide polymorphisms

bg :

ß-giardin

gdh :

Glutamate dehydrogenase

tpi :

Triosephosphate isomerase

gp60 :

60-KDa glycoprotein

References

  1. Ryan UM, Feng Y, Fayer R, Xiao L. Taxonomy and molecular epidemiology of Cryptosporidium and Giardia - a 50 year perspective (1971–2021). Int J Parasitol. 2021;51:1099–119.

    Article  CAS  PubMed  Google Scholar 

  2. Karimi P, Shafaghi-Sisi S, Meamar AR, Razmjou E. Molecular identification of Cryptosporidium, Giardia, and Blastocystis from stray and household cats and cat owners in Tehran. Iran Sci Rep. 2023;13:1554.

    Article  CAS  PubMed  Google Scholar 

  3. Karim MR, Zhang S, Jian F, Li J, Zhou C, Zhang L, et al. Multilocus typing of Cryptosporidium spp. and Giardia duodenalis from non-human primates in China. Int J Parasitol. 2014;44:1039–47.

    Article  CAS  PubMed  Google Scholar 

  4. Xiao L, Fayer R. Molecular characterisation of species and genotypes of Cryptosporidium and Giardia and assessment of zoonotic transmission. Int J Parasitol. 2008;38:1239–55.

    Article  CAS  PubMed  Google Scholar 

  5. Ryan U, Xiao L, Read C, Zhou L, Lal AA, Pavlasek I. Identification of novel Cryptosporidium genotypes from the Czech Republic. Appl Environ Microbiol. 2003;69:4302–7.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  6. Tůmová L, Ježková J, Prediger J, Holubová N, Sak B, Konečný R, et al. Cryptosporidium mortiferum n. sp. (Apicomplexa: Cryptosporidiidae), the species causing lethal cryptosporidiosis in Eurasian red squirrels (Sciurus vulgaris). Parasit Vectors. 2023;16:235.

    Article  PubMed  PubMed Central  Google Scholar 

  7. Kopacz Ż, Kváč M, Piesiak P, Szydłowicz M, Hendrich AB, Sak B, et al. Cryptosporidium baileyi pulmonary infection in immunocompetent woman with benign neoplasm. Emerg Infect Dis. 2020;26:1958–61.

    Article  PubMed  PubMed Central  Google Scholar 

  8. Hernández-Castro C, Dashti A, Köster PC, Bailo B, López A, Llorente MT, González-Barrio D, Sánchez S, Carmena D. First report of rodent-adapted Cryptosporidium wrairi in an immunocompetent child. Spain Parasitol Res. 2022;121:3007–11.

    Article  PubMed  Google Scholar 

  9. Ryan U, Zahedi A, Feng Y, Xiao L. An update on zoonotic Cryptosporidium species and genotypes in humans. Animals (Basel). 2021;11:3307.

    Article  PubMed  PubMed Central  Google Scholar 

  10. Feng Y, Xiao L. Zoonotic potential and molecular epidemiology of Giardia species and giardiasis. Clin Microbiol Rev. 2011;24:110–40.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  11. Sprong H, Caccio SM, van der Giessen JW, ZOOPNET network and partners. Identification of zoonotic genotypes of Giardia duodenalis. PLoS Negl Trop Dis. 2009;3:e558.

  12. Berrilli F, D'Alfonso R, Giangaspero A, Marangi M, Brandonisio O, Kaboré Y, et al. Giardia duodenalis genotypes and Cryptosporidium species in humans and domestic animals in Cote d’Ivoire: occurrence and evidence for environmental contamination. Trans R Soc Trop Med Hyg. 2012;106:191–5.

    Article  PubMed  Google Scholar 

  13. Cibot M, McLennan MR, Kvac M, Sak B, Asiimwe C, Petrzelkova K. Sparse evidence for Giardia intestinalis, Cryptosporidium spp. and Microsporidia infections in humans, domesticated animals and wild nonhuman primates sharing a farm-forest mosaic landscape in Western Uganda. Pathogens. 2021;10:933.

    Article  PubMed  PubMed Central  Google Scholar 

  14. de Lucio A, Bailo B, Aguilera M, Cardona GA, Fernandez-Crespo JC, Carmena D. No molecular epidemiological evidence supporting household transmission of zoonotic Giardia duodenalis and Cryptosporidium spp. from pet dogs and cats in the province of Alava, Northern Spain. Acta Trop. 2017;170:48–56.

    Article  PubMed  Google Scholar 

  15. Robertson LJ, Björkman C, Axén C, Fayer R. Cryptosporidiosis in farmed animals. Cryptosporidium: parasite and disease; Springer Vienna. 2014;149–235.

  16. Xiao L, Escalante L, Yang C, Sulaiman I, Escalante AA, Montali RJ, Fayer R, Lal AA. Phylogenetic analysis of Cryptosporidium parasites based on the small-subunit rRNA gene locus. Appl Environ Microbiol. 1999;65:1578–83.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  17. Alves M, Xiao L, Sulaiman I, Lal AA, Matos O, Antunes F. Subgenotype analysis of Cryptosporidium isolates from humans, cattle, and zoo ruminants in Portugal. J Clin Microbiol. 2003;41:2744–7.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  18. Jiang W, Roellig DM, Guo Y, Li N, Feng Y, Xiao L. Development of a subtyping tool for zoonotic pathogen Cryptosporidium canis. J Clin Microbiol. 2021;59:e02474-e2520.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  19. Stensvold CR, Beser J, Axen C, Lebbad M. High applicability of a novel method for gp60-based subtyping of Cryptosporidium meleagridis. J Clin Microbiol. 2014;52:2311–9.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  20. Appelbee AJ, Frederick LM, Heitman TL, Olson ME. Prevalence and genotyping of Giardia duodenalis from beef calves in Alberta. Canada Vet Parasitol. 2003;112:289–94.

    Article  CAS  PubMed  Google Scholar 

  21. Lalle M, Pozio E, Capelli G, Bruschi F, Crotti D, Caccio SM. Genetic heterogeneity at the beta-giardin locus among human and animal isolates of Giardia duodenalis and identification of potentially zoonotic subgenotypes. Int J Parasitol. 2005;35:207–13.

    Article  CAS  PubMed  Google Scholar 

  22. Caccio SM, Beck R, Lalle M, Marinculic A, Pozio E. Multilocus genotyping of Giardia duodenalis reveals striking differences between assemblages A and B. Int J Parasitol. 2008;38:1523–31.

    Article  CAS  PubMed  Google Scholar 

  23. Sulaiman IM, Fayer R, Bern C, Gilman RH, Trout JM, Schantz PM, et al. Triosephosphate isomerase gene characterization and potential zoonotic transmission of Giardia duodenalis. Emerg Infect Dis. 2003;9:1444–52.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  24. Geurden T, Geldhof P, Levecke B, Martens C, Berkvens D, Casaert S, et al. Mixed Giardia duodenalis assemblage A and E infections in calves. Int J Parasitol. 2008;38:259–64.

    Article  CAS  PubMed  Google Scholar 

  25. Levecke B, Geldhof P, Claerebout E, Dorny P, Vercammen F, Caccio SM, et al.  Molecular characterisation of Giardia duodenalis in captive non-human primates reveals mixed assemblage A and B infections and novel polymorphisms. Int J Parasitol. 2009;39:1595–601.

    Article  PubMed  Google Scholar 

  26. Yang Y, Zhou Y, Cheng W, Pan X, Xiao P, Shi Y, et al. Prevalence and determinants of Cryptosporidium infection in an underdeveloped rural region of southwestern China. Am J Trop Med Hyg. 2017;96:595–601.

    PubMed  PubMed Central  Google Scholar 

  27. Dong S, Yang Y, Wang Y, Yang D, Yang Y, Shi Y, Li C, Li L, Chen Y, Jiang Q, Zhou Y. Prevalence of Cryptosporidium infection in the global population: a systematic review and meta-analysis. Acta Parasitol. 2020;65:882–9.

    Article  PubMed  Google Scholar 

  28. He DL. Human intestinal parasite infection in Hui Ethnic group in Qinghai Province. Chin High Alt Med Biol. 2001;4–6 (in Chinese).

  29. Li ZY. Investigation of Giardia lamblia infection in Huaying city, Sichuan Province. Parasitoses Infect Dis. 2003;34–5 (in Chinese).

  30. El Kettani S, Azzouzi EM, Maata A. Prevalence of Giardia intestinalis in a farming population using sewage water in agriculture, Settat, Morocco. Med Mal Infect. 2006;36:322–8.

    PubMed  Google Scholar 

  31. Kifleyohannes T, Nodtvedt A, Debenham JJ, Tysnes KR, Terefe G, Robertson LJ. Cryptosporidium and Giardia infections in humans in Tigray, Northern Ethiopia: an unexpectedly low occurrence of anthropozoonotic transmission. Acta Trop. 2022;231:106450.

    Article  PubMed  Google Scholar 

  32. Foronda P, Bargues MD, Abreu-Acosta N, Periago MV, Valero MA, Valladares B, et al. Identification of genotypes of Giardia intestinalis of human isolates in Egypt. Parasitol Res. 2008;103:1177–81.

    Article  CAS  PubMed  Google Scholar 

  33. Wang WY, Chu HS, Lin PC, Lee TF, Kuo KT, Hsueh PR, Hu FR, Wang IJ. Outbreak of microsporidial keratoconjunctivitis associated with water contamination in swimming pools in Taiwan. Am J Ophthalmol. 2018;194:101–9.

    Article  PubMed  Google Scholar 

  34. Geng HL, Yan WL, Wang JM, Meng JX, Zhang M, Zhao JX, et al. Meta-analysis of the prevalence of Giardia duodenalis in sheep and goats in China. Microb Pathog. 2023;179:106097.

    Article  PubMed  Google Scholar 

  35. Hamidinejat H, Jalali MH, Jafari RA, Nourmohammadi K. Molecular determination and genotyping of Cryptosporidium spp. in fecal and respiratory samples of industrial poultry in Iran. Asian Pac J Trop Med. 2014;7:517–20.

    Article  CAS  PubMed  Google Scholar 

  36. Baroudi D, Khelef D, Goucem R, Adjou KT, Adamu H, Zhang H, et al. Common occurrence of zoonotic pathogen Cryptosporidium meleagridis in broiler chickens and turkeys in Algeria. Vet Parasitol. 2013;196:334–40.

    Article  PubMed  Google Scholar 

  37. Lin X, Xin L, Qi M, Hou M, Liao S, Qi N, et al. Dominance of the zoonotic pathogen Cryptosporidium meleagridis in broiler chickens in Guangdong, China, reveals evidence of cross-transmission. Parasit Vectors. 2022;15:188.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  38. Liao C, Wang T, Koehler AV, Fan Y, Hu M, Gasser RB. Molecular investigation of Cryptosporidium in farmed chickens in Hubei Province, China, identifies ‘zoonotic’ subtypes of C. meleagridis. Parasit Vectors. 2018;11:484.

    Article  PubMed  PubMed Central  Google Scholar 

  39. Guo Y, Ryan U, Feng Y, Xiao L. Association of common zoonotic pathogens with concentrated animal feeding operations. Front Microbiol. 2021;12:810142.

    Article  PubMed  Google Scholar 

  40. Wang Y, Zhang B, Li J, Yu S, Zhang N, Liu S, et al. Development of a quantitative real-time PCR assay for detection of Cryptosporidium spp. infection and threatening caused by Cryptosporidium parvum subtype IIdA19G1 in diarrhea calves from northeastern China. Vector Borne Zoonotic Dis. 2021;21:179–90.

    Article  PubMed  Google Scholar 

  41. Wang Y, Cao J, Chang Y, Yu F, Zhang S, Wang R, et al. Prevalence and molecular characterization of Cryptosporidium spp. and Giardia duodenalis in dairy cattle in Gansu, northwest China. Parasite. 2020;27:62.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  42. Hu S, Liu Z, Yan F, Zhang Z, Zhang G, Zhang L, et al. Zoonotic and host-adapted genotypes of Cryptosporidium spp., Giardia duodenalis and Enterocytozoon bieneusi in dairy cattle in Hebei and Tianjin, China. Vet Parasitol. 2017;248:68–73.

    Article  PubMed  Google Scholar 

  43. Li F, Wang H, Zhang Z, Li J, Wang C, Zhao J, et al. Prevalence and molecular characterization of Cryptosporidium spp. and Giardia duodenalis in dairy cattle in Beijing. China Vet Parasitol. 2016;219:61–5.

    Article  PubMed  Google Scholar 

  44. Wu Y, Zhang K, Zhang Y, Jing B, Chen Y, Xu C, et al. Genetic diversity of Cryptosporidium parvum in neonatal dairy calves in Xinjiang, China. Pathogens. 2020;9:692.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  45. Cai M, Guo Y, Pan B, Li N, Wang X, Tang C, et al. Longitudinal monitoring of Cryptosporidium species in pre-weaned dairy calves on five farms in Shanghai, China. Vet Parasitol. 2017;241:14–9.

    Article  PubMed  Google Scholar 

  46. Li N, Wang R, Cai M, Jiang W, Feng Y, Xiao L. Outbreak of cryptosporidiosis due to Cryptosporidium parvum subtype IIdA19G1 in neonatal calves on a dairy farm in China. Int J Parasitol. 2019;49:569–77.

    Article  PubMed  PubMed Central  Google Scholar 

  47. Wang R, Wang H, Sun Y, Zhang L, Jian F, Qi M, et al. Characteristics of Cryptosporidium transmission in preweaned dairy cattle in Henan, China. J Clin Microbiol. 2011;49:1077–82.

    Article  PubMed  PubMed Central  Google Scholar 

  48. Feng Y, Gong X, Zhu K, Li N, Yu Z, Guo Y, et al. Prevalence and genotypic identification of Cryptosporidium spp., Giardia duodenalis and Enterocytozoon bieneusi in pre-weaned dairy calves in Guangdong, China. Parasit Vectors. 2019;12:41.

    Article  PubMed  PubMed Central  Google Scholar 

  49. Costa D, Razakandrainibe R, Valot S, Vannier M, Sautour M, Basmaciyan L, Gargala G, Viller V, Lemeteil D, Ballet JJ; French national network on surveillance of human cryptosporidiosis; Dalle F, Favennec L. Epidemiology of cryptosporidiosis in France from 2017 to 2019. Microorganisms. 2020;8:1358.

    Article  PubMed  PubMed Central  Google Scholar 

  50. Ibrahim MA, Abdel-Ghany AE, Abdel-Latef GK, Abdel-Aziz SA, Aboelhadid SM. Epidemiology and public health significance of Cryptosporidium isolated from cattle, buffaloes, and humans in Egypt. Parasitol Res. 2016;115:2439–48.

    Article  CAS  PubMed  Google Scholar 

  51. Garcia RJ, Ogbuigwe P, Pita AB, Velathanthiri N, Knox MA, Biggs PJ, et al. First report of novel assemblages and mixed infections of Giardia duodenalis in human isolates from New Zealand. Acta Trop. 2021;220:105969.

    Article  Google Scholar 

  52. Yu F, Li D, Chang Y, Wu Y, Guo Z, Jia L, et al. Molecular characterization of three intestinal protozoans in hospitalized children with different disease backgrounds in Zhengzhou, central China. Parasit Vectors. 2019;12:543.

    Article  PubMed  PubMed Central  Google Scholar 

  53. Wang L, Zhang H, Zhao X, Zhang L, Zhang G, Guo M, et al. Zoonotic Cryptosporidium species and Enterocytozoon bieneusi genotypes in HIV-positive patients on antiretroviral therapy. J Clin Microbiol. 2013;51:557–63.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  54. Feng Y, Ryan UM, Xiao L. Genetic diversity and population structure of Cryptosporidium. Trends Parasitol. 2018;34:997–1011.

    Article  CAS  PubMed  Google Scholar 

  55. Yang Z, Zhao W, Wang J, Ren G, Zhang W, Liu A. Molecular detection and genetic characterizations of Cryptosporidium spp. in farmed foxes, minks, and raccoon dogs in northeastern China. Parasitol Res. 2018;117:169–75.

    Article  PubMed  Google Scholar 

  56. Zhang X, Jian Y, Li X, Ma L, Karanis G, Qigang C, et al. Molecular detection and prevalence of Cryptosporidium spp. infections in two types of domestic farm animals in the Qinghai-Tibetan Plateau Area (QTPA) in China. Parasitol Res. 2017;117:233–9.

    Article  PubMed  Google Scholar 

  57. Cama V, Gilman RH, Vivar A, Ticona E, Ortega Y, Bern C, et al. Mixed Cryptosporidium infections and HIV. Emerg Infect Dis. 2006;12:1025–8.

    Article  PubMed  PubMed Central  Google Scholar 

  58. Xiao L, Cama VA, Cabrera L, Ortega Y, Pearson J, Gilman RH. Possible transmission of Cryptosporidium canis among children and a dog in a household. J Clin Microbiol. 2007;45:2014–6.

    Article  PubMed  PubMed Central  Google Scholar 

  59. Wang W, Wei Y, Cao S, Wu W, Zhao W, Guo Y, et al. Divergent Cryptosporidium species and host-adapted Cryptosporidium canis subtypes in farmed minks, raccoon dogs and foxes in Shandong, China. Front Cell Infect Microbiol. 2022;12:980917.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  60. Li J, Lin X, Zhang L, Qi N, Liao S, Lv M, et al. Molecular characterization of Cryptosporidium spp. in domestic pigeons (Columba livia domestica) in Guangdong Province, Southern China. Parasitol Res. 2015;114:2237–41.

    Article  PubMed  Google Scholar 

  61. Wang R, Wang F, Zhao J, Qi M, Ning C, Zhang L, et al. Cryptosporidium spp. in quails (Coturnix coturnix japonica) in Henan China: molecular characterization and public health significance. Vet Parasitol. 2012;187:534–7.

    Article  CAS  PubMed  Google Scholar 

  62. Wang R, Jian F, Sun Y, Hu Q, Zhu J, Wang F, et al. Large-scale survey of Cryptosporidium spp. in chickens and Pekin ducks (Anas platyrhynchos) in Henan, China: prevalence and molecular characterization. Avian Pathol. 2010;39:447–51.

    Article  PubMed  Google Scholar 

  63. Elkarim Laatamna A, Holubova N, Sak B, Kvac M. Cryptosporidium meleagridis and C. baileyi (Apicomplexa) in domestic and wild birds in Algeria. Folia Parasitol (Praha). 2017;2017:018.

    Google Scholar 

  64. Krumkamp R, Aldrich C, Maiga-Ascofare O, Mbwana J, Rakotozandrindrainy N, Borrmann S, et al. Transmission of Cryptosporidium species among human and animal local contact networks in sub-saharan Africa: a multicountry study. Clin Infect Dis. 2021;72:1358–66.

    Article  CAS  PubMed  Google Scholar 

  65. Essid R, Menotti J, Hanen C, Aoun K, Bouratbine A. Genetic diversity of Cryptosporidium isolates from human populations in an urban area of Northern Tunisia. Infect Genet Evol. 2018;58:237–42.

    Article  CAS  PubMed  Google Scholar 

  66. Silverlas C, Mattsson JG, Insulander M, Lebbad M. Zoonotic transmission of Cryptosporidium meleagridis on an organic Swedish farm. Int J Parasitol. 2012;42:963–7.

    Article  PubMed  Google Scholar 

  67. Wang P, Li S, Zou Y, Du ZC, Song DP, Wang P, et al. The infection and molecular characterization of Cryptosporidium spp. in diarrheic pigs in southern China. Microb Pathog. 2022;165:105459.

    Article  CAS  PubMed  Google Scholar 

  68. Zou Y, Ma JG, Yue DM, Zheng WB, Zhang XX, Zhao Q, et al. Prevalence and risk factors of Cryptosporidium infection in farmed pigs in Zhejiang, Guangdong, and Yunnan Provinces, China. Trop Anim Health Prod. 2017;49:653–7.

    Article  PubMed  Google Scholar 

  69. Zhang W, Yang F, Liu A, Wang R, Zhang L, Shen Y, et al. Prevalence and genetic characterizations of Cryptosporidium spp. in pre-weaned and post-weaned piglets in Heilongjiang Province, China. PLoS ONE. 2013;8:e67564.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  70. Leoni F, Amar C, Nichols G, Pedraza-Díaz S, McLauchlin J. Genetic analysis of Cryptosporidium from 2414 humans with diarrhoea in England between 1985 and 2000. J Med Microbiol. 2006;55:703–7.

    Article  CAS  PubMed  Google Scholar 

  71. Moore CE, Elwin K, Phot N, Seng C, Mao S, Suy K, et al. Molecular characterization of Cryptosporidium Species and Giardia duodenalis from symptomatic Cambodian children. PLoS Negl Trop Dis. 2016;10:e0004822.

    Article  PubMed  PubMed Central  Google Scholar 

  72. Liu H, Shen Y, Yin J, Yuan Z, Jiang Y, Xu Y, et al. Prevalence and genetic characterization of Cryptosporidium, Enterocytozoon, Giardia and Cyclospora in diarrheal outpatients in China. BMC Infect Dis. 2014;14:25.

    Article  PubMed  PubMed Central  Google Scholar 

  73. Sannella AR, Suputtamongkol Y, Wongsawat E, Caccio SM. A retrospective molecular study of Cryptosporidium species and genotypes in HIV-infected patients from Thailand. Parasit Vectors. 2019;12:91.

    Article  PubMed  PubMed Central  Google Scholar 

  74. Hancke D, Suarez OV. A review of the diversity of Cryptosporidium in Rattus norvegicus, R. rattus and Mus musculus: What we know and challenges for the future. Acta Trop. 2022;226:106244.

    Article  PubMed  Google Scholar 

  75. Khan SM, Witola WH. Past, current, and potential treatments for cryptosporidiosis in humans and farm animals: a comprehensive review. Front Cell Infect Microbiol. 2023;13:1115522.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  76. Wang Y, Zhang K, Chen Y, Li X, Zhang L. Cryptosporidium and cryptosporidiosis in wild birds: a One Health perspective. Parasitol Res. 2021;120:3035–44.

    Article  PubMed  Google Scholar 

  77. Agholi M, Hatam GR, Motazedian MH. HIV/AIDS-associated opportunistic protozoal diarrhea. AIDS Res Hum Retroviruses. 2013;29:35–41.

    Article  PubMed  PubMed Central  Google Scholar 

  78. Jiang Y, Ren J, Yuan Z, Liu A, Zhao H, Liu H, et al. Cryptosporidium andersoni as a novel predominant Cryptosporidium species in outpatients with diarrhea in Jiangsu Province. China BMC Infect Dis. 2014;14:555.

    Article  PubMed  Google Scholar 

  79. Wu Y, Chang Y, Chen Y, Zhang X, Li D, Zheng S, et al. Occurrence and molecular characterization of Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi from Tibetan sheep in Gansu, China. Infect Genet Evol. 2018;64:46–51.

    Article  CAS  PubMed  Google Scholar 

  80. Cui Z, Wang L, Cao L, Sun M, Liang N, Wang H, et al. Genetic characteristics and geographic segregation of Giardia duodenalis in dairy cattle from Guangdong Province, southern China. Infect Genet Evol. 2018;66:95–100.

    Article  PubMed  Google Scholar 

  81. Abdel-Moein KA, Saeed H. The zoonotic potential of Giardia intestinalis assemblage E in rural settings. Parasitol Res. 2016;115:3197–202.

    Article  PubMed  Google Scholar 

  82. Fantinatti M, Bello AR, Fernandes O, Da-Cruz AM. Identification of Giardia lamblia assemblage E in humans points to a new anthropozoonotic cycle. J Infect Dis. 2016;214:1256–9.

    Article  PubMed  Google Scholar 

  83. Zahedi A, Field D, Ryan U. Molecular typing of Giardia duodenalis in humans in Queensland—first report of assemblage E. Parasitology. 2017;144:1154–61.

    Article  CAS  PubMed  Google Scholar 

  84. Iwashita H, Sugamoto T, Takemura T, Tokizawa A, Vu TD, Nguyen TH, et al. Molecular epidemiology of Giardia spp. in northern Vietnam: potential transmission between animals and humans. Parasite Epidemiol Control. 2021;12:e00193.

    Article  PubMed  Google Scholar 

  85. Jian Y, Zhang X, Li X, Schou C, Charalambidou I, Ma L, et al. Occurrence of Cryptosporidium and Giardia in wild birds from Qinghai Lake on the Qinghai-Tibetan Plateau. China Parasitol Res. 2021;120:615–28.

    Article  PubMed  Google Scholar 

  86. Graczyk TK, Fayer R, Trout JM, Lewis EJ, Farley CA, Sulaiman I, et al. Giardia sp. cysts and infectious Cryptosporidium parvum oocysts in the facal of migratory Canada geese (Branta canadensis). Appl Environ Microbiol. 1998;64:2736–8.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  87. Cao S, Xu M, Jiang Y, Liu H, Yuan Z, Sun L, et al. Prevalence and genetic characterization of Cryptosporidium, Giardia and Enterocytozoon in chickens from Ezhou, Hubei. China Front Vet Sci. 2020;7:30.

    Article  PubMed  Google Scholar 

  88. Ballweber LR, Xiao L, Bowman DD, Kahn G, Cama VA. Giardiasis in dogs and cats: update on epidemiology and public health significance. Trends Parasitol. 2010;26:180–9.

    Article  PubMed  Google Scholar 

  89. Lee H, Jung B, Lim JS, Seo MG, Lee SH, Choi KH, et al. Multilocus genotyping of Giardia duodenalis from pigs in Korea. Parasitol Int. 2020;78:102154.

    Article  CAS  PubMed  Google Scholar 

  90. Minetti C, Taweenan W, Hogg R, Featherstone C, Randle N, Latham SM, et al. Occurrence and diversity of Giardia duodenalis assemblages in livestock in the UK. Transbound Emerg Dis. 2014;61:e60–7.

    Article  CAS  PubMed  Google Scholar 

  91. Xu H, Jin Y, Wu W, Li P, Wang L, Li N, et al. Genotypes of Cryptosporidium spp., Enterocytozoon bieneusi and Giardia duodenalis in dogs and cats in Shanghai, China. Parasit Vectors. 2016;9:121.

    Article  PubMed  PubMed Central  Google Scholar 

  92. Traub RJ, Inpankaew T, Reid SA, Sutthikornchai C, Sukthana Y, Robertson ID, et al. Transmission cycles of Giardia duodenalis in dogs and humans in temple communities in Bangkok–a critical evaluation of its prevalence using three diagnostic tests in the field in the absence of a gold standard. Acta Trop. 2009;111:125–32.

    Article  PubMed  Google Scholar 

  93. Broglia A, Weitzel T, Harms G, Caccio SM, Nockler K. Molecular typing of Giardia duodenalis isolates from German travellers. Parasitol Res. 2013;112:3449–56.

    Article  CAS  PubMed  Google Scholar 

  94. Xiao L, Feng Y. Molecular epidemiologic tools for waterborne pathogens Cryptosporidium spp. and Giardia duodenalis. Food Waterborne Parasitol. 2017;8–9:14–32.

    Article  PubMed  PubMed Central  Google Scholar 

  95. Ryan U, Caccio SM. Zoonotic potential of Giardia. Int J Parasitol. 2013;43:943–56.

    Article  CAS  PubMed  Google Scholar 

  96. Squire SA, Ryan U. Cryptosporidium and Giardia in Africa: current and future challenges. Parasit Vectors. 2017;10:195.

    Article  PubMed  PubMed Central  Google Scholar 

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Acknowledgements

We express gratitude to the owners for cooperation during the collection of human and animal fecal samples.

Funding

The study was supported by the Natural Science Foundation of Heilongjiang Province of China (no. LH2022H010). The funder had no role in study design, data collection and analysis, or preparation of the manuscript.

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FY and WZ conceived and designed experiments. YZ, LY, and BY collected human and animal samples and demographic data. YH carried out the experiments, while AL, YH, and HL analyzed and interpreted the data. YH and FY drafted the manuscript, and all authors read and approved the final version.

Corresponding authors

Correspondence to Weizhe Zhang or Fengkun Yang.

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Ethics approval and consent to participate

This project was verbally explained to all participants, and human fecal samples were collected from individuals who voluntarily agreed to participate in the present study. All animal fecal samples were acquired with the permissions from their respective owners. The study protocol was reviewed and approved by the Research Ethics Committee and the Animal Ethics Committee of Harbin Medical University (approval no. HMUIRB2022011).

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Not applicable.

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The authors declare that they have no competing interests.

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Supplementary Information

Additional file 1: Table S1.

Homology analysis of the SSU rRNA genes of Cryptosporidium-positive samples at the nucleotide level.

Additional file 2: Table S2.

Assemblage distributions of G. duodenalis in domestic animals in Heilongjiang Province.

Additional file 3: Table S3.

Homology analysis of the SSU rRNA, bg, gdh, and tpi genes of G. duodenalis-positive samples at the nucleotide and amino acid levels.

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Hao, Y., Liu, A., Li, H. et al. Molecular characterization and zoonotic potential of Cryptosporidium spp. and Giardia duodenalis in humans and domestic animals in Heilongjiang Province, China. Parasites Vectors 17, 155 (2024). https://doi.org/10.1186/s13071-024-06219-3

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