Epidemiology of Cryptosporidium infection in cattle in China: a review

Global prevalence of Cryptosporidium andersoni in dairy cattle: A systematic review and meta-analysis

Cryptosporidium spp. are apicomplexan parasites commonly found in the gastrointestinal tracts of humans and in a wide range of animals. Infection is prevalent in dairy cattle and results in diarrhea and increased mortality with significant production losses. Cryptosporidium andersoni is commonly seen in asymptomatic adult cattle and has been associated with gastritis, reduced milk yield, and poor weight gain. However, a meta-analysis of C. andersoni infection in dairy cattle globally has not yet been published. We searched databases for studies on the global prevalence of C. andersoni infection in dairy cattle published from January 1, 2000, to December 31, 2022. The prevalence of C. andersoni infection in dairy cattle was estimated using a random effects model. In total, 86 publications from 30 countries were included in the final quantitative analysis. The global prevalence of C. andersoni in dairy cattle was 4.7% (95% confidence interval [CI]: 4.5-4.9%, 2,554/54,627). European dairy cattle had the highest rate of C. andersoni infection at 8.8% (961/10,944). A univariate meta-regression analysis indicated that the age of cattle (P = 0.002) and sample collection year (P = 0.025) might be sources of heterogeneity. This systematic review suggests that globally, dairy cattle exhibit a low level of C. andersoni infection; however, the geographical distribution of infection is extensive. C. andersoni mainly infects the stomach of cattle and causes no obvious clinical symptoms after infection but is thought to be responsible for reduced milk production. Therefore, subclinical Cryptosporidium infection in dairy cattle is easily overlooked. Cattle with subclinical infections can produce feces containing oocysts that are inadvertently not safely handled, which can then infect healthy dairy cattle and even cause Cryptosporidium infection in dairy cattle breeders. Therefore, prevention of C. andersoni transmission in asymptomatic cattle is an important issue that should not be neglected.

Molecular characterization of common zoonotic protozoan parasites and bacteria causing diarrhea in dairy calves in Ningxia Hui Autonomous Region, China

Diarrhea caused by zoonotic pathogens is one of the most common diseases in dairy calves, threatening the health of young animals. Humans are also at risk, in particular children. To explore the pathogens causing diarrhea in dairy calves, the present study applied PCR-based sequencing tools to investigate the occurrence and molecular characteristics of three parasites (Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi) and three bacterial pathogens (Escherichia coli, Clostridium perfringens, and Salmonella spp.) in 343 fecal samples of diarrheic dairy calves from five farms in Lingwu County, Ningxia Hui Autonomous Region, China. The total positive rate of these pathogens in diarrheic dairy calves was 91.0% (312/343; 95% CI, 87.9-94.0), with C. perfringens (61.5%, 211/343; 95% CI, 56.3-66.7) being the dominant one. Co-infection with two to five pathogens was found in 67.3% (231/343; 95% CI, 62.4-72.3) of investigated samples. There were significant differences (p < 0.05) in the positive rates of Cryptosporidium spp. and diarrheagenic E. coli among farms, age groups, and seasons. Two Cryptosporidium species (C. parvum and C. bovis) and five gp60 subtypes of C. parvum (IIdA15G1, IIdA20G1, IIdA19G1, IIdA14G1, and a novel IIdA13G1) were identified. Two assemblages (assemblage E and zoonotic assemblage A) of G. duodenalis and six ITS genotypes of E. bieneusi (J, Henan-IV, EbpC, I, EbpA, and ESH-01) were observed. Four virulence genes (eaeA, stx1, stx2, and st) of diarrheagenic E. coli and one toxin type (type A) of C. perfringens were detected. Our study enriches our knowledge on the characteristics and zoonotic potential of diarrhea-related pathogens in dairy calves.

Prevalence and associated risk factors of Cryptosporidium infection in calves and hospitalized humans in Libo Kemkem, North Western Ethiopia

BACKGROUND

Cryptosporidium infection is one of the major causes of acute gastroenteritis and diarrhoea caused by a protozoan parasite affecting vertebrates and humans. The disease is prevalent in cases of immunocompromised individuals. Despite the impact of the diseases in calf and hospitalized humans, well-documented studies are not available in the study area.

OBJECTIVES

The objectives of this study were to determine the prevalence of Cryptosporidium infection in calves and hospitalized humans and assess the major associated risk factors associated with Cryptosporidium infection in calves and hospitalized humans.

METHOD

A cross-sectional study was conducted from November 2020 to March 2021 on calf and human Cryptosporidium infection in Libo Kemkem District, North West Ethiopia. A total of 193 calves and 122 human stool samples admitted to the hospital were used for this study. Three kebeles were selected purposely, and individual calves were selected using a simple random sampling method. A number of sampled calves were allocated proportionally to the selected kebeles. Human samples were collected using a systematic random sampling method. Faecal and stool samples were examined using a modified Ziehl-Neelsen staining method.

RESULT

The overall prevalence of calf and human Cryptosporidium infection found in this study was 15.5% and 11.5%, respectively. Age of calf, breed, body condition, water source, faecal consistency and hygienic condition were found significantly (p < 0.05) associated with Cryptosporidium infection in the calf. Similarly, the source of potable water, immunocompromisation and contact with domestic animals were found to be significantly (p < 0.05) associated with Cryptosporidium infection in humans.

CONCLUSION

There was a higher prevalence of Cryptosporidium infection in calves and humans in Libo Kemkem District. Therefore, the implementation of proper prevention methods of zoonotic Cryptosporidium infection between calf and human beings through significant risk factors is mandatory. Furthermore, additional studies to investigate the levels of economic importance of the disease should be conducted.

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

Cryptosporidium spp., Enterocytozoon bieneusi, and Giardia duodenalis are common intestinal pathogens that infect humans and animals. To date, research regarding these three protozoa in the Ningxia Hui Autonomous Region (Ningxia) has mostly been limited to a single pathogen, and comprehensive data on mixed infections are unavailable. This study aimed to evaluate the zoonotic potential of these three protozoa. In this study, small subunit ribosomal RNA (SSU rRNA) and 60 kDa glycoprotein (gp60) genes of Cryptosporidium; internal transcribed spacer (ITS) gene of E. bieneusi; and SSU rRNA, glutamate dehydrogenase (gdh), triosephosphate isomerase (tpi), and beta-giardin (bg) genes of G. duodenalis were examined. DNA extraction, polymerase chain reaction, and sequence analysis were performed on fecal samples collected from 320 dairy cattle at three intensive dairy farms in Ningxia in 2021 to determine the prevalence and genetic characteristics of these three protozoa. The findings revealed that 61.56% (197/320) of the samples were infected with at least one protozoan. The overall prevalence of Cryptosporidium was 19.38% (62/320), E. bieneusi was 41.56% (133/320), and G. duodenalis was 29.38% (94/320). This study identified four Cryptosporidium species (C. bovis, C. andersoni, C. ryanae, and C. parvum) and the presence of mixed infections with two or three Cryptosporidium species. C. bovis was the dominant species in this study, while the dominant C. parvum subtypes were IIdA15G1 and IIdA20G1. The genotypes of E. bieneusis were J, BEB4, and I alongside the novel genotypes NX1-NX8, all belonging to group 2, with genotype J being dominant. G. duodenalis assemblages were identified as assemblages E, A, and B, and a mixed infection involving assemblages A + E was identified, with assemblage E being the dominant one. Concurrently, 11 isolates formed 10 different assemblage E multilocus genotypes (MLGs) and 1 assemblage A MLG and assemblage E MLGs formed 5 subgroups. To the best of our knowledge, this is the first report on mixed infection with two or three Cryptosporidium species in cattle in Ningxia and on the presence of the C. parvum subtype IIdA20G1 in this part of China. This study also discovered nine genotypes of E. bieneusis and novel features of G. duodenalis assemblages in Ningxia. This study indicates that dairy cattle in this region may play a significant role in the zoonotic transmission of Cryptosporidium spp., E. bieneusi, and G. duodenalis.

Cryptosporidium spp. Infection and Genotype Identification in Pre-Weaned and Post-Weaned Calves in Yunnan Province, China

BACKGROUND

Cryptosporidium is a globally distributed zoonotic protozoan parasite in humans and animals. Infection is widespread in dairy cattle, especially in calves, resulting in neonatal enteritis, production losses and high mortality. However, the occurrence of Cryptosporidium spp. in pre- and post-weaned calves in Yunnan Province remains unclear.

METHODS

We collected 498 fecal samples from Holstein calves on 10 different farms in four regions of Yunnan Province. Nested PCR and DNA sequencing were used to determine the infection, species and genotypes of Cryptosporidium spp. in these animals.

RESULTS

The overall occurrence of Cryptosporidium spp. in Holstein calves was 32.9% (164/498), and the prevalence in pre- and post-weaned calves was 33.5% (106/316) and 31.9% (58/182), respectively. Four Cryptosporidium species were identified in these animals, namely C. bovis (n = 119), C. parvum (n = 23), C. ryanae (n = 20) and C. andersoni (n = 2). Based on sequencing analysis of the 60 kDa glycoprotein gene of C. bovis, C. parvum and C. ryanae, six subtypes of C. bovis (XXVIe, XXVIb, XXVIf, XXVIa XXVIc and XXVId), two subtypes of C. parvum (IIdA19G1 and IIdA18G1) and four subtypes of C. ryanae (XXIf, XXId, XXIe and XXIg) were identified.

CONCLUSIONS

These results provide essential information to understand the infection rate, species diversity and genetic structure of Cryptosporidium spp. populations in Holstein pre-weaned and post-weaned calves in Yunnan Province. Further, the presence of IIdA18G1 and IIdA19G1 in C. parvum implies significant animal and public health concerns, which requires greater attention and more preventive measures.

Molecular characterization and zoonotic risk assessment of Cryptosporidium spp. in children and calves in Bangladesh

Cryptosporidium is a gastro-intestinal protozoan parasite that has been found to infect both humans and livestock. This study investigated the parasite in 998 fecal samples from Bangladeshi children (n = 299) and calves (n = 699) to determine its prevalence, genetic variation, and zoonotic importance. The nested PCR and sequencing of the SSU rRNA gene in the samples showed a Cryptosporidium infection rate of 2.3% (7/299) in children and 15.7% (110/699) in calves. Statistical analysis revealed insignificant variations in Cryptosporidium infections among children across age, gender, and study area, while in calves, the infection rate significantly differed based on location and breed. Genotyping of seven human isolates of Cryptosporidium confirmed C. hominis (n = 5) and C. parvum (n = 2). After characterizing 110 Cryptosporidium isolates from calves, C. andersoni (n = 55), C. ryanae (n = 29), C. bovis (n = 14), C. parvum (n = 10), C. ubiquitum (n = 1), and C. occultus (n = 1) were identified. Cryptosporidium hominis and C. parvum-positive samples were further subjected to nested PCR and sequencing of the glycoprotein 60 (gp60) gene for subtyping. Four C. hominis subtypes (IaA19R3, IaA23R3, IbA9G3, and IdA15G1) and one C. parvum subtype (IIdA15G1) were observed. In conclusion, Cryptosporidium was prevalent in calves but less common in children in the study locations, and the presence of zoonotic Cryptosporidium species and subtypes in calves raises concerns regarding zoonotic transmission to humans.

Prevalence and Molecular Characterization of Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi in Cattle in Heilongjiang Province, Northeast China

Crytosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi are important diarrheal pathogens with a global distribution that threatens the health of humans and animals. Despite cattle being potential transmission hosts of these protozoans, the associated risks to public health have been neglected. In the present study, a total of 1155 cattle fecal samples were collected from 13 administrative regions of Heilongjiang Province. The prevalence of Cryptosporidium spp., G. duodenalis, and E. bieneusi were 5.5% (64/1155; 95% CI: 4.2-6.9), 3.8% (44/1155; 95% CI: 2.7-4.9), and 6.5% (75/1155; 95% CI: 5.1-7.9), respectively. Among these positive fecal samples, five Cryptosporidium species (C. andersoni, C. bovis, C. ryanae, C. parvum, and C. occultus), two G. duodenalis assemblages (E and A), and eight E. bieneusi genotypes (BEB4, BEB6, BEB8, J, I, CHS7, CHS8, and COS-I) were identified. Phylogenetic analysis showed that all eight genotypes of E. bieneusi identified in the present study belonged to group 2. It is worth noting that some species/genotypes of these intestinal protozoans are zoonotic, suggesting a risk of zoonotic disease transmission in endemic areas. The findings expanded our understanding of the genetic composition and zoonotic potential of Cryptosporidium spp., G. duodenalis, and E. bieneusi in cattle in Heilongjiang Province.

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

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

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

Cryptosporidium spp. are key gastrointestinal protists in humans and animals worldwide. Infected cattle are considered the main source of cryptosporidiosis outbreaks in humans. However, little is known about the genetic makeup of Cryptosporidium populations in Shanxi province, China. We analyzed 858 fecal samples collected from farms in Shanxi. The presence of Cryptosporidium spp. was determined via polymerase chain reaction and subsequent sequence analysis of the small subunit rRNA gene as well as restriction fragment length polymorphism analysis. Cryptosporidium parvum was subtyped following sequence analysis of the 60 kDa glycoprotein gene (gp60). The overall prevalence of Cryptosporidium in cattle was 11.19%, with a prevalence of 13.30% and 8.67% in Lingqiu and Yingxian, respectively. The overall prevalence of Cryptosporidium in dairy and beef cattle was 10.78% and 11.50%, respectively. Cryptosporidium infection was detected across all analyzed age groups. The overall prevalence of Cryptosporidium in diarrhea and nondiarrhea samples was 18.24% and 9.72%, respectively, whereas that in intensively farmed and free-range cattle was 17.40% and 3.41%, respectively. We identified five Cryptosporidium species, with C. andersoni being the dominant species. Further, two cases of mixed infections of Cryptosporidium species were detected. All identified C. parvum isolates belonged to the subtype IIdA17G1.

Rapid detection of Cryptosporidium spp. in diarrheic cattle feces by isothermal recombinase polymerase amplification assays

As a zoonotic parasite, Cryptosporidium spp. could cause severe diarrhea mainly in calves and children globally. Monitoring and prevention of Cryptosporidium spp.'s prevalence is of great significance in both economy and public health aspects. In this study, specific primers and probes were designed within the conserved region of 18S rRNA gene for Cryptosporidium spp. and recombinase polymerase amplification assays based on the fluorescence monitoring (real-time RPA) as well as combined with a lateral flow strip (LFS RPA) were developed. Both of the two RPA assays allowed the exponential amplification of the target fragment within 20 min. After incubation on a metal bath at 42 °C, the LFS RPA results were displayed on the lateral flow strip within 5 min while real-time RPA allowed the real-time observation of the results in Genie III at 39 °C. The RPA assays showed high specificity for Cryptosporidium spp. without any cross-reaction with other tested pathogens causing diarrhea in cattle. With the recombinant plasmid DNA containing the 18S rRNA gene of Cryptosporidium spp. serving as a template, the limit of detection for real-time RPA and LFS RPA assays were 14.6 and 12.7 copies/reaction, respectively. Moreover, the RPA assays were validated by testing diarrheic cattle fecal samples and compared with a real-time PCR. The positive ratio of Cryptosporidium spp. was 24.04 % (44/183) and 26.23 % (48/183) in both RPA assays and real-time PCR assay, respectively, and the kappa coefficient value was 0.942. The diagnostic specificity and diagnostic sensitivity of both RPA assays were 100 % and 91.67 %, respectively. Forty-one of 48 positive samples were successfully sequenced and four Cryptosporidium species were detected, including C. parvum (n = 20), C. andersoni (n = 17), C. bovis (n = 3) and C. ryanae (n = 1). The developed RPA assays are easy to operate and faster to obtain the detection results, and they are suiting for the point-of-care detection and facilitating the prevention and control of Cryptosporidium spp. infections.

Longitudinal follow-up reveals occurrence of successive Cryptosporidium bovis and Cryptosporidium ryanae infections by different subtype families in dairy cattle

Cryptosporidium bovis and Cryptosporidium ryanae are common species causing cryptosporidiosis in cattle. Data accumulated thus far indicate that the infection patterns of the two species could be different between areas with and without Cryptosporidium parvum. To better understand the infection dynamics of these two species, cross-sectional and longitudinal studies of Cryptosporidium spp. were conducted using genotyping and subtyping tools. In the cross-sectional survey, analysis of 634 faecal samples from two farms identified only C. bovis and C. ryanae in pre-weaned calves. Two birth cohorts of 61 and 78 calves were followed longitudinally over a 12 month period, which revealed the shedding of C. bovis oocysts started at 1-2 weeks of age and peaked initially at 6-8 weeks of age. Altogether calves experienced four infections by six subtype families of C. bovis, with each infection caused by different subtype families. In contrast, the shedding of C. ryanae oocysts started at 2-4 weeks of age, and the two infections were caused by different subtype families. The cumulative incidence of C. bovis infection was 100% (58/58, 32/32) on both farms, compared with 84.4-98.3% (27/32 and 57/58) for C. ryanae infection. Overall, the mean duration of oocyst shedding in the cohort studies was 3.8-4.0 weeks for C. bovis compared with 2.1 weeks for C. ryanae. The oocyst shedding intensity was high (mean oocysts per gram of faeces was over 105) during the first infection with each species but became significantly lower in the later infections. Cryptosporidium ryanae was associated with the occurrence of diarrhea on one farm, while C. bovis was not. The data indicate that there is an early occurrence of C. bovis and C. ryanae in pre-weaned calves with high infection intensity in the absence of C. parvum. Calves infected with the same Cryptosporidium sp. multiple times could be associated with the presence of subtype-specific immunity.

Molecular Identification and Genotyping of Cryptosporidium spp. and Blastocystis sp. in Cattle in Representative Areas of Shanxi Province, North China

Both Cryptosporidium spp. and Blastocystis sp. are common intestinal protozoa, which can cause zoonotic diseases and economic losses to livestock industry. To evaluate the prevalence and genetic population structure of Cryptosporidium spp. and Blastocystis sp. in beef and dairy cattle in Shanxi Province, north China, a total of 795 fecal samples were collected from beef and dairy cattle in three representative counties in Shanxi Province, and these fecal samples were examined using molecular approaches based on 18S small-subunit ribosomal RNA (SSU rRNA) of Cryptosporidium spp. and Blastocystis sp., respectively. Among 795 cattle fecal samples, 23 were detected as Cryptosporidium-positive and 103 were detected as Blastocystis-positive, and the overall prevalence of Cryptosporidium spp. and Blastocystis sp. in cattle in Shanxi Province was 2.9% and 13.0%, respectively. For Cryptosporidium spp., DNA sequence analysis indicated that all 23 positive samples were identified as C. andersoni. Furthermore, five known subtypes (ST1, ST10, ST14, ST21 and ST26) and three unknown subtypes of Blastocystis sp. were detected among 103 positive samples using DNA sequence analysis. This study reported the occurrence and prevalence of Cryptosporidium spp. and Blastocystis sp. in cattle in Shanxi Province for the first time, which extends the geographical distribution of these two zoonotic parasites and provides baseline data for the prevention and control of these two important zoonotic parasites in cattle in Shanxi Province.

Prevalence and molecular characterization of Cryptosporidium spp. in dairy cattle in Central Inner Mongolia, Northern China

BACKGROUND

Cryptosporidium is a gastrointestinal protozoan that widely exists in nature, it is an established zoonotic pathogen. Infected cattle are considered to be associated with cryptosporidiosis outbreaks in humans. In the present study, we aimed to assess the prevalence and species distribution of Cryptosporidium in dairy cattle in Central Inner Mongolia.

METHODS

We focused on the small subunit ribosomal RNA gene (SSU rRNA) of Cryptosporidium and 60-kDa glycoprotein gene (gp60) of Cryptosporidium parvum. We collected 505 dairy cattle manure samples from 6 sampling sites in Inner Mongolia in 2021; the samples were divided into 4 groups based on age. DNA extraction, polymerase chain reaction (PCR), sequence analysis, and restriction fragment length polymorphism (RFLP) using SspI and MboII restriction endonucleases were performed. RFLP analysis was performed to determine the prevalence and species distribution of Cryptosporidium.

RESULTS

SSU rRNA PCR revealed that the overall prevalence of Cryptosporidium infection was 29.90% (151/505), with a prevalence of 37.67% (55/146) and 26.74% (96/359) in diarrheal and nondiarrheal samples, respectively; these differences were significant. The overall prevalence of Cryptosporidium infection at the 6 sampling sites ranged from 0 to 47.06% and that among the 4 age groups ranged from 18.50 to 43.81%. SSU rRNA sequence analysis and RFLP analysis revealed the presence of 4 Cryptosporidium species, namely, C. bovis (44.37%), C. andersoni (35.10%), C. ryanae (21.85%), and C. parvum (11.92%), along with a mixed infection involving two or three Cryptosporidium species. Cryptosporidium bovis or C. andersoni was the most common cause of infection in the four age groups. The subtype of C. parvum was successfully identified as IIdA via gp60 analysis; all isolates were identified as the subtype IIdA19G1.

CONCLUSIONS

To the best of our knowledge, this is the first report of dairy cattle infected with four Cryptosporidium species in Inner Mongolia, China, along with a mixed infection involving two or three Cryptosporidium species, with C. bovis and C. andersoni as the dominant species. Moreover, this is the first study to identify C. parvum subtype IIdA19G1 in cattle in Inner Mongolia. Our study findings provide detailed information on molecular epidemiological investigation of bovine cryptosporidiosis in Inner Mongolia, suggesting that dairy cattle in this region are at risk of transmitting cryptosporidiosis to humans.

Modeling cryptosporidiosis in humans and cattle: Deterministic and stochastic approaches

Cryptosporidiosis is a zoonotic disease caused by Cryptosporidium. The disease poses a public and veterinary health problem worldwide. A deterministic model and its corresponding continuous time Markov chain (CTMC) stochastic model are developed and analyzed to investigate cryptosporidiosis transmission dynamics in humans and cattle. The basic reproduction number R 0 for the deterministic model and stochastic threshold for the CTMC stochastic model are computed by the next generation matrix method and multitype branching process, respectively. The normalized forward sensitivity index method is used to determine the sensitivity index for each parameter in R 0 . Per capita birth rate of cattle, the rate of cattle to acquire cryptosporidiosis infection from the environment and the rate at which infected cattle shed Cryptosporidium oocysts in the environment play an important role in the persistence of the disease whereas Cryptosporidium oocysts natural death rate, cattle recovery rate and cattle natural death rate are most negative sensitive parameters in the dynamics of cryptosporidiosis. Numerical results for CTMC stochastic model show that the likelihood of cryptosporidiosis extinction is high when it arises from an infected human. However, there is a major outbreak if cryptosporidiosis emerges either from infected cattle or from Cryptosporidium oocysts in the environment or when it emerges from all three infectious compartments. Therefore to control the disease, control measures should focus on maintaining personal and cattle farm hygiene and decontaminating the environment to destroy Cryptosporidium oocysts.

Investigation of Parasitic Infection in Crocodile Lizards (Shinisaurus crocodilurus) Using High-Throughput Sequencing

The highly endangered crocodile lizard (Shinisaurus crocodilurus) continues to be impacted by disease, especially in captive breeding populations. In this paper, based on high-throughput sequencing, we investigated parasitic infections in captive and wild crocodile lizard populations in the Daguishan National Nature Reserve and Guangdong Luokeng Shinisaurus crocodilurus National Nature Reserve. The results show that the overall parasitic infection rate in crocodile lizards was 33.33% (23/69). Four parasite genera were detected, including Eimeria, Cryptosporidium, Nematopsis, and Acanthamoeba, with infection rates of 15.94% (11/69), 17.39% (12/69), 7.25% (5/69), and 4.35% (3/69), respectively. Significant differences in the infection rate were found between the different parasite species (χ2 = 8.54, p < 0.05, chi-squared test). The parasitic infection rates in the captive and wild populations were 39.29% (22/56) and 7.69% (1/13), respectively, which were significantly different (p < 0.05, Fisher’s exact test). However, no significant differences in the infection rates of the four parasite genera were found between the captive and wild populations (p > 0.05, Fisher’s exact test). The parasitic infection rates in Daguishan and Luokeng were 34.09% (15/44) and 32.00% (8/25), respectively, which were not significantly different (p > 0.05, Fisher’s exact test). However, significant differences in terms of species were found in the two reserves (p < 0.01, Fisher’s exact test). Only Cryptosporidium infection showed a significant difference between the two regions (p < 0.01, Fisher’s exact test). Our results suggest that captive crocodile lizards are more susceptible to parasitic diseases than wild crocodile lizards and that Cryptosporidium infection varies by geographical region. This study provides basic information about the parasites of endangered crocodile lizards, as well as a reference for disease control and conservation.

Eimeria falciformis secretes extracellular vesicles to modulate proinflammatory response during interaction with mouse intestinal epithelial cells

BACKGROUND

Protozoan parasite secretions can be triggered by various modified media and diverse physicochemical stressors. Equally, host-parasite interactions are known to co-opt the exchange and secretion of soluble biochemical components. Analysis of Eimeria falciformis sporozoite secretions in response to interaction with mouse intestinal epithelial cells (MIECs) may reveal parasite secretory motifs, protein composition and inflammatory activities of E. falciformis extracellular vesicles (EVs).

METHODS

Eimeria falciformis sporozoites were allowed to interact with inactivated MIECs. Parasite secretions were separated into EV and vesicle-free (VF) fractions by discontinuous centrifugation and ultracentrifugation. Secreted EVs were purified in an iodixanol density gradient medium and the protein composition of both EV and VF fractions were analyzed by liquid chromatoraphy-tandem mass spectroscopy. The inflammatory activities of E. falciformis sporozoite EV on MIECs were then investigated.

RESULTS

During the interaction of E. falciformis sporozoites with inactivated MIECs, the parasite secreted VF and vesicle-bound molecules. Eimeria falciformis vesicles are typical pathogenic protozoan EVs with a mean diameter of 264 ± 2 nm, and enclosed heat shock protein (Hsp) 70 as classical EV marker. Refractile body-associated aspartyl proteinase (or eimepsin), GAP45 and aminopeptidase were the main components of E. falciformis sporozoite EVs, while VF proteins include Hsp90, actin, Vps54 and kinases, among others. Proteomic data revealed that E. falciformis EV and VF proteins are aggregates of bioactive, antigenic and immunogenic molecules which act in concert for E. falciformis sporozoite motility, pathogenesis and survival. Moreover, in MIECs, E. falciformis EVs induced upregulation of gene expression and secretion of IL-1β, IL-6, IL-17, IL-18, MCP1 as well as pyroptosis-dependent caspase 11 and NLRP6 inflammasomes with the concomitant secretion of lactate dehydrogenase.

CONCLUSIONS

Eimeria falciformis sporozoite interaction with MIECs triggered the secretion of immunogenic and antigenic proteins. In addition, E. falciformis sporozoite EVs constitute parasite-associated molecular pattern that induced inflammatory response and cell death. This study offers additional insight in the secretion and protein composition of E. falciformis secretomes as well as the proinflammatory functions of E. falciformis sporozoite EVs.

Occurrence and Molecular Characterization of Cryptosporidium spp. in Dairy Cattle and Dairy Buffalo in Yunnan Province, Southwest China

Simple Summary

Cryptosporidium spp. are important gastrointestinal pathogens of humans and animals, causing diarrheal diseases. Cattle are considered as one of the main reservoirs of Cryptosporidium for humans. We first report the occurrence of Cryptosporidium spp. in dairy cattle (14.7%, 65/442) and dairy buffalo (1.1%, 3/258) in Yunnan Province of China. The results of this study suggest that divergent Cryptosporidium spp. (such as C. andersoni, C. bovis, C. ryanae, and C. parvum) can be found in asymptomatic dairy cattle and dairy buffalo in Yunnan, China. The IIdA18G1 subtype of C. parvum, which infects humans and other animals, was also found in this study. Thus, attention should be paid towards preventing the transmission of Cryptosporidium spp. in cattle and humans in Yunnan Province.

Abstract

Cryptosporidium spp. are important foodborne and waterborne pathogens in humans and animals, causing diarrheal diseases. Cattle are one of the reservoirs of Cryptosporidium infection in humans. However, data on the occurrence of Cryptosporidium spp. in cattle in Yunnan Province remains limited. A total of 700 fecal samples were collected from Holstein cows (n = 442) and dairy buffaloes (n = 258) in six counties of Yunnan Province. The occurrence and genotypes of Cryptosporidium spp. were analyzed using nested PCR and DNA sequencing. Furthermore, the C. andersoni isolates were further analyzed using multilocus sequence typing (MLST) at four gene loci (MS1, MS2, MS3, and MS16), and the C. parvum isolate was subtyped by 60-kDa glycoprotein (gp60) loci. The occurrence of Cryptosporidium spp. in Holstein cows and dairy buffaloes was 14.7% (65/442) and 1.1% (3/258), respectively. Of these positive samples, 56 Holstein cow samples represented C. andersoni, four Holstein cow samples represented C. bovis, three Holstein cow samples represented C. ryanae, and one represented C. parvum. Meanwhile, only three dairy buffalo samples represented C. ryanae. MLST analysis of subtypes of C. andersoni detected four subtypes, including A5A4A2A1 (n = 7), A4A4A4A1 (n = 7), A1A4A4A1 (n = 2), and A4A4A2A1 (n = 1). One C. parvum isolate was identified as the IIdA18G1 subtype. These results revealed the high occurrence and high genetic diversity of Cryptosporidium spp. in Holstein cows in Yunnan Province, enriching the knowledge of the population genetic structure of Cryptosporidium spp. in Yunnan Province.

Eimeria proteins: order amidst disorder

Apicomplexans are important pathogens that cause severe infections in humans and animals. The biology and pathogeneses of these parasites have shown that proteins are intrinsically modulated during developmental transitions, physiological processes and disease progression. Also, proteins are integral components of parasite structural elements and organelles. Among apicomplexan parasites, Eimeria species are an important disease aetiology for economically important animals wherein identification and characterisation of proteins have been long-winded. Nonetheless, this review seeks to give a comprehensive overview of constitutively expressed Eimeria proteins. These molecules are discussed across developmental stages, organelles and sub-cellular components vis-à-vis their biological functions. In addition, hindsight and suggestions are offered with intention to summarise the existing trend of eimerian protein characterisation and to provide a baseline for future studies.

Cross-Border Investigations on the Prevalence and Transmission Dynamics of Cryptosporidium Species in Dairy Cattle Farms in Western Mainland Europe

Cryptosporidium is an apicomplexan parasitic protist, which infects a wide range of hosts, causing cryptosporidiosis disease. In farms, the incidence of this disease is high in animals such as cows, leading to extensive economic loss in the livestock industry. Infected cows may also act as a major reservoir of Cryptosporidium spp., in particular C. parvum, the most common cause of cryptosporidiosis in these animals. This poses a risk to the trading of livestock, to other farms via breeding centres, and to human health. This study is a part of a global project aimed at strategies to tackle cryptosporidiosis. To reach this target, it was essential to determine whether prevalence was dependent on the studied countries or if the issue was borderless. Indeed, C. parvum occurrence was assessed across dairy farms in certain regions of Belgium, France, and the Netherlands. At the same time, the animal-to-animal transmission of the circulating C. parvum subtypes was studied. To accomplish this, we analysed 1084 faecal samples, corresponding to 57 dairy farms from all three countries. To this end, 18S rRNA and gp60 genes fragments were amplified, followed by DNA sequencing, which was subsequently used for detection and subtyping C. parvum. Bioinformatic and phylogenetic methods were integrated to analyse and characterise the obtained DNA sequences. Our results show 25.7%, 24.9% and 20.8% prevalence of Cryptosporidium spp. in Belgium, France, and the Netherlands respectively. Overall, 93% of the farms were Cryptosporidium positive. The gp60 subtyping demonstrated a significant number of the C. parvum positives belonged to the IIa allelic family, which has been also identified in humans. Therefore, this study highlights how prevalent C. parvum is in dairy farms and further suggests cattle as a possible carrier of zoonotic C. parvum subtypes, which could pose a threat to human health.

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

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

Cryptosporidium infection in cattle and humans in Ethiopia: A systematic review and meta-analysis

Cryptosporidium is an intracellular coccidian parasite causing gastrointestinal disturbances resulting in diarrhoea in humans and animals. It is more frequently detected in calves and early childhood, and one of the major causes of mortality in low-income countries. National estimates of Cryptosporidium infection rate in cattle and humans are lacking in Ethiopia. Therefore, this systematic review and meta-analysis estimated the prevalence and assess the risk factors of Cryptosporidium infection in cattle and humans over 20 years. Article searches were made using PubMed, HINARI, Research Gates, AJOLs and Google Scholar databases. Studies that met the inclusion criteria under the preferred reporting items for systematic reviews and meta-analyses (PRISMA) checklist were used. Random effects models and Inverse Variance Index were used to calculate the pooled prevalence of cryptosporidiosis and heterogeneity among studies, respectively. A total of 23 eligible studies published between 2000 and 2020 were selected for this study. The estimated pooled prevalence of cryptosporidiosis was found to be 16.2% and 11% in cattle and humans, respectively. Ten Cryptosporidium species were documented with cattle and human-based studies. C. andersoni, C. parvum, C. bovis and C. ryanae were the reported species in cattle. Similarly, in humans, seven types of Cryptosporidium species (such as C. parvum, C. hominis, C. viatorum, C. felis, C. meleagridis, C. canis and C. xiaoi) were recorded. C. parvum and C. hominis were the dominant and responsible species for human illness. Using gp60 gene locus analysis, various zoonotic C. parvum subgenotypes were determined in humans; but it was limited in anthroponotic C. hominis. In conclusion, the overall prevalence of Cryptosporidium infection in cattle and humans was high and linked with several risk factors. Thus, there is a need for further epidemiological and genetic diversity studies, and awareness of creations on the disease to provide strategies that mitigate the disease in cattle and humans.

Molecular detection of Cryptosporidium: an emerging parasite in different water sources of 2010 flood-affected district Nowshera, Pakistan

Cryptosporidium is a water-borne zoonotic parasite worldwide, usually found in lakes and rivers contaminated with sewage and animal wastes, causing outbreaks of cryptosporidiosis. In this study, 300 water samples were collected from four designated places of flood-affected district Nowshera consist of different water sources to find out the prevalence of Cryptosporidium via polymerase chain reaction (PCR). The overall prevalence of Cryptosporidium was 30.33% (91/300) with more prevalent 44% in drain water and low 5% in bore/tube well water. The prevalence in open well and tap water was recorded 33% and 20%, respectively. The highest prevalence was recorded in summer (June-September). The result of this study ensures enormous contamination of drinking water that requires appropriate treatment, cleaning and filtration to provide safe drinking water. Preventing water-borne disease and proper treatment of water supplies is essential to public health.

First report of the prevalence and genetic characterization of Giardia duodenalis and Cryptosporidium spp. in Yunling cattle in Yunnan Province, southwestern China

Yunling cattle is an unique cattle breed distributed in Yunnan Province, southwestern China. It is yet to know whether Yunling cattle are infected with Giardia duodenalis and Cryptosporidium spp.. The objectives of the present study were to investigate the prevalence and characterize the assemblages of G. duodenalis and species of Cryptosporidium spp. in Yunling cattle in Yunnan province. The overall prevalence of G. duodenalis and Cryptosporidium spp. were 10.49% (41/391) and 0.77% (3/391), respectively. The age was considered as the risk factor for Yunling cattle infection with G. duodenalis (χ² = 8.082, OR = 2.56, P = 0.004). Two assemblages of G. duodenalis, assemblage A (n = 1) and assemblage E (n = 40), were identified by amplification of the β-giardin (bg) and glutamate dehydrogenase (gdh) gene loci using the nested PCR methods. Furthermore, Cryptosporidium andersoni (n = 1) and Cryptosporidium ryanae (n = 2) were detected by nested PCR targeting the small subunit (SSU) rRNA gene. This is the first report of G. duodenalis and Cryptosporidium spp. in Yunling cattle in China, which provided baseline date for further studies of the prevalence, genetic identity, and public health potential of these parasites in Yunling cattle.

Prevalence of infection by Cryptosporidium spp. in calves and associated risk factors in Northeastern Brazil

ABSTRACT Cryptosporidium spp. are zoonotic protozoa, frequently associated with diarrhea in calves, which are responsible for important economic losses. The aim of this study was to assess the prevalence of infection by Cryptosporidium spp. and its associated risk factors among calves raised in a milk production region of Northeastern Brazil. Fecal samples (n = 385) were obtained from young animals (up to ten months old) and evaluated by means of centrifugal fecal sedimentation in formalin-ether followed by the modified Ziehl-Neelsen staining technique. In addition, Odds Ratio (OR) was calculated to evaluate associations between variables and infection by these protozoa. Out of all samples analyzed, 25.7% (99/385) scored positive for the presence of Cryptosporidium spp. Contact with other species (goat and sheep) (OR = 3.33; p = 0.000), use of a semi-intensive rearing system (OR = 1.70; p = 0.024) and absence of hygienic conditions (fecal contamination of food and water) (OR = 1.64; p = 0.029) were considered to be risk factors. Data herein reported shows that the implementation of hygienic-sanitary measures on the farms studied, it is imperative to reduce Cryptosporidium spp. infection and consequently the economic impact caused by this pathogen.

The Age-Related Cryptosporidium Species Distribution in Asymptomatic Cattle from North-Western SPAIN

Simple Summary

An age-related distribution of Cryptosporidium species has been reported in cattle, with the pathogenic and zoonotic C. parvum being predominant in suckling calves, C. bovis and C. ryanae being predominant in post-weaned calves and C. andersoni being predominant in adults. However, variants to this pattern have recently been reported. Unravelling the age-related species distribution pattern in cattle from a particular region will allow determining those age classes posing a higher risk to public and animal health. Thus, fecal samples from asymptomatic cattle were collected in north-western Spain. Cryptosporidium detection and species identification was performed by molecular methods. Cryptosporidium prevalence was 16.7%; it significantly decreased with age. Cryptosporidium andersoni, C. bovis, C. occultus, C. parvum, C. ryanae and C. xiaoi were identified. Cryptosporidium parvum was predominant in calves younger than 1 month and C. bovis was predominant in the rest of the age groups. The presence of C. parvum in all age groups implies animal and public health concerns. The predominance of C. bovis in cattle older than 1 month supports the idea that the age-related pattern of Cryptosporidium species described in cattle is not fully consistent, and thus further studies are needed to identify those factors determining the species distribution.

Abstract

An age-related distribution of Cryptosporidium species has been reported in cattle, with C. parvum being predominant in suckling calves, C. bovis and C. ryanae being predominant in post-weaned calves and C. andersoni being predominant in adults. However, variants to this pattern have recently been reported. Thus, fecal samples (n = 594) from asymptomatic cattle were collected in north-western Spain. Animals were classified as <1 month (G1), 1–2 months (G2), 2–12 months (G3), 12–24 months (G4) and >2 years (G5). Cryptosporidium detection and species identification were performed by SSU rRNA PCR. Individual Cryptosporidium prevalence was 16.7%; it significantly decreased with age. Cryptosporidium parvum was predominant in G1 and C. bovis was predominant in the rest of the age classes; C. bovis and C. ryanae were especially prevalent in G2 and G3. Cryptosporidium occultus was not found in suckling calves. Finally, C. andersoni and C. xiaoi were occasionally detected in G5. The presence of C. parvum in all age classes implies significant animal and public health concerns. The predominance of C. bovis in cattle older than 1 month supports the idea that the age-related pattern of Cryptosporidium species described in cattle is not fully consistent, and thus further studies are still needed to identify those factors determining the species distribution.

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

Cryptosporidium spp. and Giardia duodenalis are common gastrointestinal parasites with a broad range of hosts, including humans, livestock, and wildlife. To examine the infection status and assess the zoonotic potential of Cryptosporidium spp. and G. duodenalis in dairy cattle in Gansu, China, a total of 1414 fecal samples were collected from the rectum, with one sample collected from each individual animal. All the samples were tested using nested PCR based on the small subunit ribosomal RNA (SSU rRNA) gene of Cryptosporidium spp. and G. duodenalis. The overall infection rates of Cryptosporidium spp. and Giardia duodenalis were 4.2% (n = 59) and 1.0% (n = 14), respectively. Four Cryptosporidium species were identified: C. andersoni (n = 42), C. parvum (n = 12), C. bovis (n = 5), and C. ryanae (n = 1). In further analyses of subtypes of C. parvum isolates based on the 60 kDa glycoprotein (gp60) gene, five were successfully subtyped as IIdA19G1 (n = 4) and IIdA15G1 (n = 1). All 14 G. duodenalis isolates were identified as assemblage E using the triosephosphate isomerase (tpi) gene. The relatively low positive rates of Cryptosporidium spp. and G. duodenalis detected here and the predominance of non-human pathogenic species/assemblages of these parasites indicated their unique transmission dynamics in this area and the low level of threat posed to public health. However, continuous monitoring and further studies of these parasites should be conducted for the prevention and control of these pathogens.

Molecular detection of Cryptosporidium spp. and Enterocytozoon bieneusi in Longjiang Wagyu cattle in Northeastern China

Cryptosporidium spp. and Enterocytozoon bieneusi are two important zoonotic pathogens that can cause diarrhea and other gastrointestinal illnesses in humans and animals. However, the prevalence and genotype of the parasites in Longjiang Wagyu cattle in Heilongjiang Province, Northeast China have not been reported. In the present study, a total of 423 fecal samples of Longjiang Wagyu cattle collected from different farms in Heilongjiang Province, Northeast China, were examined for Cryptosporidium spp. and E. bieneusi using nested PCR. The overall infection rates for Cryptosporidium spp. and E. bieneusi were 6.38% (n = 27) and 7.09% (n = 30), respectively. The prevalence in different age groups ranged from 3.80% (95% confidence interval (CI) 1.01-6.59) to 8.36% (95% CI 4.83-11.90) for Cryptosporidium spp. and 5.97% (95% CI 2.52-9.43) to 7.94% (95% CI 4.49-11.40) for E. bieneusi. By analyzing the DNA sequences of the small subunit (SSU) rRNA gene, two Cryptosporidium species were detected in this study, namely C. parvum (n = 25) and C. ryanae (n = 2). The IIdA20G1 subtype was further identified by using the 60-kDa glycoprotein (gp60) gene of C. parvum. E. bieneusi was identified using three known sequences through the analysis of internal transcribed spacer (ITS) sequences: J (n = 23), I (n = 5), and BEB4 (n = 2), and all belonged to group 2. The results indicated that some of the Cryptosporidium species and E. bieneusi genotypes identified in Longjiang Wagyu cattle in the study areas might have zoonotic potential.

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

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

Co-infection risk assessment of Giardia and Cryptosporidium with HIV considering synergistic effects and age sensitivity using disability-adjusted life years

Co-infection with multiple pathogens, especially the spread of Giardia and Cryptosporidium in source water among those with immunodeficiency, is common worldwide, which will result in an increase in overall risk. In this study, the quantitative microbial risk assessment model was used to estimate the cumulative risk of co-infection with Giardia and Cryptosporidium promoted by HIV, considering age sensitivity. The sensitivity of population segments with different ages was estimated by the optimization method, based on clinical data of cryptosporidiosis and giardiasis with age structure. The factors of co-infection enhancement were used to quantify HIV synergism with the action of other pathogens. The removal rates of Giardia and Cryptosporidium through water treatment were estimated by a model involving turbidity and particles. The results showed that children (0-4 years) were 17.911-fold more sensitive to infection with Giardia than adults (15-64 years), and that with Cryptosporidium was 10.592-fold. Removal rates of these parasites in water treatment plants in major cities in China were estimated to be 2.03 log₁₀. Considering the HIV-synergistic and age-susceptibility effects, the cumulative risk of exposure to Giardia or Cryptosporidium was about 38.781 × 10^-6DALYs (Disability-adjusted life years) per person per year, which was much higher than the reference risk level recommended by the World Health Organization (10^-6DALYs). The methodology and results of this study will be useful in better evaluating and reducing the burden due to infection of Giardia and/or Cryptosporidium in China and other countries.

A single-cohort study of Cryptosporidium bovis and Cryptosporidium ryanae in dairy cattle from birth to calving

In order to investigate the infection dynamics of Cryptosporidium bovis and C. ryanae, a two-year prospective cohort study was performed on a dairy farm known to be free of C. parvum. Sixteen calves were recruited when newborn. Faecal samples were collected weekly until calves were nine weeks old, then monthly until calving or culling. Samples (n = 455) were examined by fluorescence microscopy, and when positive the species were determined by DNA sequencing. In calves up to nine weeks, C. bovis was found in 58.5% of the samples, C. ryanae in 9.2%, and both C. bovis and C. ryanae in 3.1%. The prevalence of shedding calves peaked at 87.5% in week five, which is earlier than many international studies have shown for C. bovis. The cumulative incidence of C. bovis reached 100% when the calves were five weeks old. In four calves, the species detected changed from C. bovis to C. ryanae or the other way around, and two samples were a combination of both species. Several individuals shed oocysts sporadically up to 16 months of age. The highest oocysts per gram faeces count was seen in week three (3.6 × 10⁶ OPG). Diarrhoea was not associated with oocyst shedding.

Effect of immunoglobulin G concentration in dairy cow colostrum and calf blood serum on Cryptosporidium spp. invasion in calves

AIM

The research aimed to test the association between the level of immunoglobulin G (IgG) in bovine colostrum and calf blood serum and to evaluate its relation to Cryptosporidium spp. invasion in calves.

MATERIALS AND METHODS

Fresh colostrum and fecal specimens from cows (n=114) as well as blood and fecal specimens from newborn calves (n=114) were collected in the dairy cattle farm. Investigated calves were separated from their mothers directly after birth and received 2 L of colostrum in two separate feedings within the first 24 h. Blood samples were taken from calves at the age of 2 days. Coprological samples were taken from calves at the age of 1, 10, and 15 days. Both colostrum and fecal samples from cows were taken on the 1st day after calf birth. Rectal fecal samples were collected separately from each calf and cow into plastic bags. The collected calf serum samples and bovine colostrum samples were tested for bovine IgG by competitive enzyme-linked immunosorbent assay kit bovine Ig. To record oocysts of Cryptosporidium spp. in feces, the flotation method was used. Binomial logistic regression was performed to ascertain the effects of IgG in bovine colostrum and calf blood serum on the likelihood of Cryptosporidium spp. infection in calves.

RESULTS

The concentration of IgG in bovine colostrum was higher (70.7±26.6 g/L, mean±standard deviation) than that in calf blood serum (13.2±6.1 g/L); the statistically significant difference was 57.4 g/L (95% confidence interval, 52.4-62.4), t (124.872)=22.536, p<0.001. Mann-Whitney's U-test showed a significant difference between samples collected on days 10 and 15 of the experiment (U=1944, z=2.330, p=0.020). The higher number of oocysts in calf feces was recorded on day 15 (median=6.5) compared to day 10 (median=4). The prevalence of calf infection from days 10 to 15 increased from 26.3 to 45.6% and was at least 3 times higher than in cows. A statistically significant positive correlation was recorded between IgG concentration of cow colostrum and calf blood serum (r (114)=0.414, p=0.001), whereas a correlation between the concentration of IgG and the intensity of Cryptosporidium spp. infection was not recorded (p>0.05). The logistic regression model was not statistically significant (χ2(2)=0.013, p=0.99 (10 days) and χ2(2)=0.100, p=0.95 (15 days)).

CONCLUSION

Mother passive transfer of immunity to the offspring through colostrum does not influence the susceptibility of calves to Cryptosporidium infestation.

Morphological updates and molecular description of Heterosentis holospinus Amin, Heckmann, & Ha, 2011 (Acanthocephala, Arhythmacanthidae) in the Pacific Ocean off Vietnam

Heterosentis holospinus Amin, Heckmann & Ha, 2011 (Arhythmacanthidae) was first described from the striped eel catfish, Plotosus lineatus (Plotosidae) in Halong Bay, Vietnam. New morphological information, scanning electron microscope images, molecular analysis, and Energy Dispersive X-ray analysis (EDXA) of hooks of specimens of H. holospinus from a new collection from the common ponyfish, Leiognathus equulus (Leiognathidae), in Quang Binh, Gulf of Tonkin, Vietnam are reported here for the first time. Additional details of the anterior trunk cone, proboscis hooks, wholly spined trunk, duck-bill-like spines with micropores, and micropore distribution, are described. The unique metal composition of hooks (EDXA) demonstrated a considerably higher level of calcium and phosphorus but lower level of sulfur at the hook basal arch than at the hook tip and edge. An analysis of our new sequences of cytochrome oxidase 1 (COI) showed that H. holospinus had low genetic variation and two haplotypes.

Effects of recycled manure solids bedding on the spread of gastrointestinal parasites in the environment of dairies and milk

The primary aim of this work was to isolate common bovine digestive tract parasites in recycled manure bedding (RMS), as well as to determine the ability of current RMS preparation procedures to eliminate these pathogens. Other objectives were to assess whether any of the aforementioned parasites could be retrieved in bulk milk from dairies using RMS and to study whether the prevalence of these parasites differed among manure of cows housed on RMS versus on straw bedding. For the study, 27 RMS farms and 61 control farms were recruited. Samples of manure from the pre-pit and milk from the bulk tank were recovered from straw-bedding farms and RMS-based farms. In addition, samples from the manure solid fraction after liquid extraction, RMS before use, and RMS currently in use were recovered from RMS herds. Parasites were first detected by double centrifugation zinc sulfate flotation to enhance isolation of gastrointestinal protozoa, and by modified Wisconsin sugar flotation for the appraisal of gastrointestinal nematodes. Cryptosporidium parasites were confirmed by nested PCR amplification and sequencing of a portion of the gene encoding the small subunit rRNA. Results revealed a high prevalence of Cryptosporidium spp. (C. parvum, C. andersoni, and C. meleagridis, identified by PCR) and Eimeria spp. (mainly E. bovis and E. zuernii) parasites in both types of farms, with a larger proportion of manure samples from RMS-bedded farms testing positive for Cryptosporidium parasites compared with manure from straw-bedded farms. Both Cryptosporidium spp. and Eimeria spp. oocysts were found at every step of RMS preparation and transformation, showing that current RMS preparation strategies do not guarantee the destruction of protozoan parasites. Cryptosporidium parvum, a potential zoonotic risk for professionals in close contact with livestock, was found to be present in 32 out of 61 straw-bedded and 24 of 27 RMS farms. No protozoan parasites were found in any sample derived from bulk milk, neither by microscopy analysis nor by molecular methods.

Cryptosporidium infections in terrestrial ungulates with focus on livestock: a systematic review and meta-analysis

Background

Cryptosporidium spp. are causative agents of gastrointestinal diseases in a wide variety of vertebrate hosts. Mortality resulting from the disease is low in livestock, although severe cryptosporidiosis has been associated with fatality in young animals.

Methods

The goal of this systematic review and meta-analysis was to review the prevalence and molecular data on Cryptosporidium infections in selected terrestrial domestic and wild ungulates of the families Bovidae (bison, buffalo, cattle, goat, impala, mouflon sheep, sheep, yak), Cervidae (red deer, roe deer, white-tailed deer), Camelidae (alpaca, camel), Suidae (boar, pig), Giraffidae (giraffes) and Equidae (horses). Data collection was carried out using PubMed, Scopus, Science Direct and Cochran databases, with 429 papers being included in this systematic analysis.

Results

The results show that overall 18.9% of ungulates from the investigated species were infected with Cryptosporidium spp. Considering livestock species (cattle, sheep, goats, pigs, horses and buffaloes), analysis revealed higher Cryptosporidium infection prevalence in ungulates of the Cetartiodactyla than in those of the Perissodactyla, with cattle (29%) being the most commonly infected farm animal.

Conclusions

Overall, the investigated domestic ungulates are considered potential sources of Cryptosporidium contamination in the environment. Control measures should be developed to reduce the occurrence of Cryptosporidium infection in these animals. Furthermore, literature on wild populations of the named ungulate species revealed a widespread presence and potential reservoir function of wildlife.

Quantitative phosphoproteome and proteome analyses emphasize the influence of phosphorylation events during the nutritional stress of Trypanosoma cruzi: the initial moments of in vitro metacyclogenesis

Phosphorylation is an important event in cell signaling that is modulated by kinases and phosphatases. In Trypanosoma cruzi, the etiological agent of Chagas disease, approximately 2% of the protein-coding genes encode for protein kinases. This parasite has a heteroxenic life cycle with four different development stages. In the midgut of invertebrate vector, epimastigotes differentiate into metacyclic trypomastigotes in a process known as metacyclogenesis. This process can be reproduced in vitro by submitting parasites to nutritional stress (NS). Aiming to contribute to the elucidation of mechanisms that trigger metacyclogenesis, we applied super-SILAC (super-stable isotope labeling by amino acids in cell culture) and LC-MS/MS to analyze different points during NS. This analysis resulted in the identification of 4205 protein groups and 3643 phosphopeptides with the location of 4846 phosphorylation sites. Several phosphosites were considered modulated along NS and are present in proteins associated with various functions, such as fatty acid synthesis and the regulation of protein expression, reinforcing the importance of phosphorylation and signaling events to the parasite. These modulated sites may be triggers of metacyclogenesis.

Shedding of Cryptosporidium in calves and dams: evidence of re-infection and shedding of different gp60 subtypes

One of the most common causes of calf diarrhoea is the parasite Cryptosporidium parvum. Two longitudinal studies were carried out on a dairy farm Scotland to determine the prevalence of Cryptosporidium species and subtypes in a group of calves and to determine whether dams were a possible source of calfhood infection. Fecal samples were collected from 25 calves from birth to 12 months in the first year. In the second year, fecal samples were collected from pregnant cows (n = 29) and their calves (n = 30) from birth to 6 months. The samples were tested for Cryptosporidium and speciated. Cryptosporidium parvum-positive samples were subtyped by GP60 fragment analysis. All calves in both studies shed Cryptosporidium during the study period. Cryptosporidium parvum was the predominant species detected in calves ⩽6 weeks of age and at 6 months of age, C. bovis and C. ryanae were detected in calves older than 4 weeks of age but ⩽6 months of age. The prevalence of Cryptosporidium was higher in younger animals than in older animals. GP60 subtyping revealed two subtypes in calves on this farm (IIaA15G2R1 and IIaA19G2R1) that differed in frequency by age. Adult cattle also shed C. parvum, of four gp60 genotypes.

Inhibitory activity of chitosan nanoparticles against Cryptosporidium parvum oocysts

Cryptosporidium is a ubiquitous harsh protozoan parasite that resists many disinfectants. It remains viable and infective for a long time in water and food causing global outbreaks. Chitosan (the deacetylated chitin molecule) was used in its nanosuspension form to evaluate its effect against Cryptosporidium parvum. The experiments were performed in vitro in serial concentrations and confirmed in mice in vivo infectivity assay. Chitosan nanoparticles (Cs NPs) were toxic to Cryptosporidium oocysts. The effect appeared to decrease the number of Cryptosporidium oocysts and altered their content. The destruction rate of oocysts was dependent on the dose of chitosan and the time of exposure (P < 0.05). Higher doses of Cs NPs over a prolonged period exhibited a significantly higher destruction rate. Using staining and light microscopy, remarkable destructive changes were observed in the oocysts' morphology. The minimal lethal dose for > 90% of oocysts was 3000 μg/ml, no mice infections in vivo were observed. The results in this study elucidate Cs NPs as an effective anti-cryptosporidial agent.

Prevalence of Cryptosporidium in dairy cattle in China during 2008-2018: A systematic review and meta-analysis

Cryptosporidium is the causative agent of cryptosporidiosis. Cryptosporidium not only has a worldwide distribution, but also can infect various hosts, including dairy cattle and humans. Although numerous researches on Cryptosporidium infection in cattle have been conducted, no nationwide study on the prevalence of Cryptosporidium infection in dairy cattle in mainland China was carried out. In this meta-analysis, five databases, including PubMed, ScienceDirect, China National Knowledge Infrastructure (CNKI), Chongqing VIP, and Wanfang, were used to search for published papers regarding Cryptosporidium infection in dairy cattle in China from inception to February 25, 2019. Our study obtained 60 eligibility studies that reported Cryptosporidium infection in dairy cattle. We estimated the pooled Cryptosporidium prevalence to be 17.0% (3,901/33,313), with 16.9% (722/5,191) in Central China, 17.4% (959/6,162) in Eastern China, 29.8% (404/2,021) in Northeastern China, 15.7% (227/2,344) in Northern China, 15.8% (1,042/11,452) in Northwestern China, 9.5% (494/5,758) in Southern China, and 13.7% (53/385) in Southwestern China. The pooled prevalence of Cryptosporidium in before 2000 group (28.0%, 944/3,417) was significantly higher than in 2000-2010 group (11.1%, 384/3,643) and after 2010 group (13.7%, 2,134/22,411). Cattle with the age of ≤ 12 months (22.5%, 2,142/12,948) had a significantly higher prevalence than those of > 12 months (9.5%, 840/10,282). The pooled prevalence of Cryptosporidium in different seasons ranged from 8.2% (343/4,552) in Autumn to 19.5% (285/1,570) in Winter. Diarrhea cattle (38%, 133/477) had a higher Cryptosporidium prevalence than non-diarrhea cattle (13.0%, 367/2423). The pooled prevalence of Cryptosporidium in different provinces was various, with the highest (35.6%, 355/1,667) in Heilongjiang province, and the lowest (4.3%, 15/440) in Tianjin province. The univariate meta-regression analyses indicated that the collection year (P = 0.002) and age of cattle (P = 0.001) might be sources of heterogeneity. This systematic review suggests that China is a country where cryptosporidiosis frequently occurs in cattle. Due to the particular relationship between dairy cattle and feeder, further research is required to investigate the links between cattle ownership and Cryptosporidium infection.

Occurrence and genotyping of Giardia duodenalis and Cryptosporidium in pre-weaned dairy calves in central Sichuan province, China

Giardia duodenalis and Cryptosporidium spp. are common human and animal pathogens. They have increasingly been reported in dairy calves in recent years; however, multilocus genotyping information for G. duodenalis and Cryptosporidium infecting pre-weaned dairy calves in southwestern China is limited. In the present study, the prevalence of G. duodenalis and Cryptosporidium spp. in pre-weaned dairy calves in central Sichuan province was determined and the pathogens were analyzed molecularly. Of 278 fecal samples from pre-weaned dairy calves, 26 (9.4%) were positive for G. duodenalis and 40 (14.4%) were positive for Cryptosporidium spp. Cryptosporidium bovis (n = 28), Cryptosporidium ryanae (n = 5) and Cryptosporidium parvum (n = 7) were detected. All seven C. parvum isolates were successfully subtyped based on the gp60 gene sequence, and only IIdA15G1 was detected. Multilocus sequence typing of G. duodenalis based on beta-giardin (bg), triose phosphate isomerase (tpi) and glutamate dehydrogenase (gdh) genes revealed 19 different assemblage E multilocus genotypes (two known and 17 unpublished genotypes). Based on eBURST analysis, a high degree of genetic diversity within assemblage E was observed in pre-weaned dairy calves in Sichuan province. To the best of our knowledge, this is the first study using multilocus sequence typing and eBURST analysis to characterize G. duodenalis in pre-weaned dairy calves in southwestern China.

Common occurrence of Cryptosporidium hominis in asymptomatic and symptomatic calves in France

BACKGROUND

Cryptosporidium spp. infections are the most frequent parasitic cause of diarrhea in humans and cattle. However, asymptomatic cases are less often documented than symptomatic cases or cases with experimentally infected animals. Cryptosporidium (C.) hominis infection accounts for the majority of pediatric cases in several countries, while C. parvum is a major cause of diarrhea in neonatal calves. In cattle Cryptosporidium spp. infection can be caused by C. parvum, C. bovis, C.andersoni and C. ryanae, and recently, reports of cattle cases of C. hominis cryptosporidiosis cases suggest that the presence of C. hominis in calves was previously underestimated.

METHODOLOGY/PRINCIPAL FINDINGS

From February to November 2015, Cryptosporidium spp. infected calves were detected in 29/44 randomly included farms from 5 geographic regions of France. C. hominis and C. parvum were found in 12/44 and 26/44 farms, respectively with higher C. hominis prevalence in the western region. In 9 farms, both C. parvum and C. hominis were detected. Eighty-six of 412 (73/342 asymptomatic and 13/70 symptomatic) one to nine-week-old calves shed C. hominis or C. parvum oocysts (15 and 71 calves, respectively), with no mixed infection detected. The predominant C. hominis IbA9G3 genotype was present in all regions, and more frequent in the western region. An incompletely characterized Ib, and the IbA13G3, IbA9G2 and IbA14G2 genotypes were present only in the western region. For C. parvum, the most frequent genotype was IIaA16G3R1 with no geographic clustering. Most C. hominis infected calves were asymptomatic, with some exceptions of IbA9G2 and IbA9G3 isolates, while C. parvum IIaA16G3R1 was associated with symptoms.

CONCLUSIONS/SIGNIFICANCE

Present results indicate for the first time that in several geographic regions of France, C. hominis was present in about one fifth of both asymptomatic and symptomatic infected calves, with isolated genotypes likely associated with human infection. Further investigations are aimed at documenting direct or indirect transmissions between livestock and humans.

Widespread Occurrence of Zoonotic Cryptosporidium Species and Subtypes in Dairy Cattle from Northeast China: Public Health Concerns

Bovine cryptosporidiosis constitutes a threat to the livestock industry and public health worldwide. In the present study we investigated dairy cattle of all ages in northeast China for the prevalence and genetic traits of Cryptosporidium. Nested polymerase chain reaction of the small subunit rRNA gene was used to identify Cryptosporidium species or genotype. The parasite was detected in 130 of 537 (24.2%) animals sampled from the cities of Harbin (35.2%, 69/196) and Qiqihar (32.1%, 61/190). Cryptosporidium parvum (87/130) was identified as the dominant species by sequence analysis followed by Cryptosporidium bovis (28/130), Cryptosporidium ryanae (5/130), Cryptosporidium andersoni (2/130), Cryptosporidium suis-like genotype (2/130), and mixed C. ryanae/ C. bovis (1/130). Subtyping of C. parvum isolates was based on the DNA polymorphisms of the 60-kDa glycoprotein gene. Subtyping of the C. parvum isolates recognized subtypes IIdA15G1 (24/87) in Harbin and IIdA20G1 (48/87) in Qiqihar. A diversity of Cryptosporidium species/genotype and subtypes was identified in cattle from northeast China. Widespread occurrence of human-pathogenic Cryptosporidium species and subtypes is of public health significance. This is the first study reporting C. parvum subtype IIdA20G1 in China. The findings improve the epidemiological knowledge of bovine cryptosporidiosis in China, highlighting the importance of ongoing Cryptosporidium surveillance.

Molecular investigation of Cryptosporidium and Giardia in pre- and post-weaned calves in Hubei Province, China

Background

The protistan pathogens Cryptosporidium and Giardia can cause significant intestinal diseases in animals and humans. Cattle, particularly calves, carrying these protists can be significant reservoirs for human infections and disease. However, little is known about the genetic make-up of Cryptosporidium and Giardia populations in cattle and other ruminants in some regions of China.

Results

In the present study, PCR-based tools were used to genetically characterise these protists in faecal samples from a total of 339 pre- and post-weaned calves from four distinct locations in Hubei Province using markers in the large (LSU) or small (SSU) subunits of nuclear ribosomal RNA genes. Cryptosporidium andersoni, C. bovis, C. ryanae and Giardia duodenalis assemblage E were detected in 0.6%, 10.9%, 4.1% and 22.6% of calves, respectively.

Conclusions

This study is the first to report the prevalence of Cryptosporidium and Giardia in pre- and post-weaned calves in Hubei Province, and encourages large-scale molecular studies of animals and humans, in an effort to better understand the epidemiology of these enteric pathogens in China.

Electronic supplementary material

The online version of this article (10.1186/s13071-017-2463-3) contains supplementary material, which is available to authorized users.

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.