Occurrence and genotypic identification of Blastocystis sp., Enterocytozoon bieneusi, and Giardia duodenalis in dairy cattle in Heilongjiang Province, China.

Blastocystis sp., Enterocytozoon bieneusi, and Giardia duodenalis are three common zoonotic intestinal parasites, and cattle are important hosts of these three intestinal protozoa. In this study, 1632 fecal samples were collected from dairy farms in Heilongjiang Province, China, and screened for Blastocystis sp., E. bieneusi, and G. duodenalis using polymerase chain reaction. Of these, 149 (9.13%) were positive for three zoonotic pathogens, including 104 (6.40%), 22 (1.35%), and 23 (1.41%) for Blastocystis sp., E. bieneusi, and G. duodenalis, respectively. Based on partial SSU rRNA gene sequencing analysis, 104 positive samples of Blastocystis sp. were found, and a total of nine known subtypes were identified, including ST10 (61), ST3 (18), ST14 (6), ST26 (7), ST24 (3), ST25 (2), ST1 (2), ST5 (2), and ST21 (1). Among these, three subtypes (ST1, ST3, and ST5) were recognized as zoonotic subtypes, and two subtypes (ST10 and ST14) were specific to animals. All 23 Giardia duodenalis-positive samples belonged to assemblage E (n = 23) based on sequenced beta-giardin (bg) and triosephosphate isomerase (tpi) genes. Three known genotypes of E. bieneusi, namely J (n = 9), I (n = 6), and BEB4 (n = 7), were identified by sequence analysis of the internal transcriptional spacer region gene. Our study provides basic data for prevention and control in Heilongjiang Province; however, further research is required to better understand the prevalence and public health significance of these pathogens in the Heilongjiang region.

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.

Assessment of potential zoonotic transmission of Giardia duodenalis from dogs and cats.

Giardia duodenalis is one of the major causes of diarrhea among humans, especially in young children. Statistical analysis revealed that the pooled prevalence of G. duodenalis in humans, dogs, and cats was 9.72% (10,921/112383), 15.60% (7510/48140), and 14.53% (1125/7740), respectively. Unquestionably, the canine-specific assemblages C and D and the feline-specific assemblage F were the dominant genotypes in dogs and cats, respectively. Additionally, the prevalence of zoonotic G. duodenalis assemblages (A and B) in dogs and cats was 23.07% (875/3792) and 41.42% (169/408), respectively, implying that the potential transmission of G. duodenalis from dogs and cats to human infection cannot be ignored. The highest frequency of potentially zoonotic assemblages was found among working dogs (3.55%, 25/705) and the 1-5 age group (22.92%, 11/48). In summary, dogs and cats have a significant role in the zoonotic transmission of G. duodenalis due to their close contact with humans and the higher frequency presence of zoonotic assemblages. Further studies are necessary to explore the presence of G. duodenalis among humans and animals and in environmental samples. Researchers should adopt a one-health approach to gain a deeper understanding of G. duodenalis in dogs and cats and potential transmission routes to humans.

Prevalence of Cryptosporidium infection in children from China: a systematic review and meta-analysis.

Cryptosporidium is an important zoonotic pathogen that causes diarrhea in humans and animals, and a leading cause of diarrhea morbidity and mortality in children under 5 years old. However, the meta-analysis of Cryptosporidium infection in children in China has not been published. We searched the databases for articles published on the prevalence of Cryptosporidium infection in children in China since the inception of these databases to 31 October 2022. The prevalence of Cryptosporidium infection in children was estimated using a random effects model. The results showed that 111 datasets from 24 provinces were selected for the final quantitative analysis. The estimated pooled Cryptosporidium infection prevalence in children in China was 2.9% (3300/126,381). The highest prevalence rate was in southwestern China (4.8%, 365/7766). Subgroup analysis indicated that the Cryptosporidium infection rate in children aged < 3 years (4.9%, 330/8428) was significantly higher than that in children aged 3-6 years (2.5%, 609/26,080) and >6 years (2.6%, 647/27,586). Six Cryptosporidium species were detected in children in China from the selected studies. C. hominis was the dominant species (77.1%, 145/188) and the proportions of subgenotype IaA14R4 of C. hominis was highest (42.8%, 62/145). The findings suggest that Chinese children is in a low level of Cryptosporidium infection, however, the geographical distribution of the infection is extensive. We suggest that measures should be taken to ensure the healthy growth of Chinese children by improving the water environment, increasing public health facilities, strengthening children's health education, and developing sound Cryptosporidium infection control programs.

Global prevalence of Cryptosporidium spp. in pigs: a systematic review and meta-analysis.

Cryptosporidium spp. are significant opportunistic pathogens causing diarrhoea in humans and animals. Pigs are one of the most important potential hosts for Cryptosporidium. We evaluated the prevalence of Cryptosporidium in pigs globally using published information and a random-effects model. In total, 131 datasets from 36 countries were included in the final quantitative analysis. The global prevalence of Cryptosporidium in pigs was 16.3% (8560/64 809; 95% confidence interval [CI] 15.0­17.6%). The highest prevalence of Cryptosporidium in pigs was 40.8% (478/1271) in Africa. Post-weaned pigs had a significantly higher prevalence (25.8%; 2739/11 824) than pre-weaned, fattening and adult pigs. The prevalence of Cryptosporidium was higher in pigs with no diarrhoea (12.2%; 371/3501) than in pigs that had diarrhoea (8.0%; 348/4874). Seven Cryptosporidium species (Cryptosporidium scrofarum, Cryptosporidium suis, Cryptosporidium parvum, Cryptosporidium muris, Cryptosporidium tyzzeri, Cryptosporidium andersoni and Cryptosporidium struthioni) were detected in pigs globally. The proportion of C. scrofarum was 34.3% (1491/4351); the proportion of C. suis was 31.8% (1385/4351) and the proportion of C. parvum was 2.3% (98/4351). The influence of different geographic factors (latitude, longitude, mean yearly temperature, mean yearly relative humidity and mean yearly precipitation) on the infection rate of Cryptosporidium in pigs was also analysed. The results indicate that C. suis is the dominant species in pre-weaned pigs, while C. scrofarum is the dominant species in fattening and adult pigs. The findings highlight the role of pigs as possible potential hosts of zoonotic cryptosporidiosis and the need for additional studies on the prevalence, transmission and control of Cryptosporidium in pigs.

Role of rodents in the zoonotic transmission of giardiasis.

Four species of Giardia out of nine have been identified in rodents based on molecular data: G. muris, G. microti, G. cricetidarum, and G. duodenalis. A total of seven G. duodenalis assemblages (A, B, C, D, E, F, G) have been identified in rodents to date. The zoonotic assemblages A and B are responsible for 74.88% (480/641) of the total identified genotypes in rodents by statistic. For sub-assemblage A in humans, AII is responsible for 71.02% (1397/1967) of the identified sub-assemblages, followed by AI with 26.39% (519/1967) and AIII with 1.17% (23/1967), indicating a significantly greater zoonotic potential for G. duodenalis infections in humans originating from animals. For sub-assemblages of type A in rodents, AI was identified in 86.89% (53/61), and AII in 4.92% (3/61). For assemblage B, 60.84% (390/641) were identified in rodents as having zoonotic potential to humans. In environmental samples, the zoonotic assemblages A and B were responsible for 83.81% (533/636) in water samples, 86.96% (140/161) in fresh produce samples, and 100% (8/8) in soil samples. The same zoonotic potential assemblage A or B simultaneously identified in humans, rodents, and environment samples had potential zoonotic transmission between humans and animals via a synanthropic environment. The infections and zoonotic potential for G. duodenalis were higher in farmed rodents and pet rodents than that in zoo, lab, and wild rodents. In conclusion, the role of rodents in zoonotic transmission of giardiasis should be noticed. In addition to rodents, dogs, cats, wild animals, and livestock could be involved in the zoonotic transmission cycle. This study aims to explore the current situation of giardiasis in rodents and seeks to delineate the role of rodents in the zoonotic transmission of giardiasis from the One Health perspective.

Cryptosporidium parvum and gp60 genotype prevalence in dairy calves worldwide: a systematic review and meta-analysis.

Cryptosporidium is a significant zoonotic pathogen that often occurs in dairy cattle. We conducted a systematic review and meta-analysis of the prevalence of Cryptosporidium parvum infection in dairy calves worldwide to help improve global animal husbandry and public policy implementation. Published articles were obtained from PubMed and Web of Science from January 1, 2000 to December 31, 2021. The prevalence of C. parvum infection in dairy calves was estimated using a random effects model, and the sources of heterogeneity were explored using meta-regression. In total, 118 datasets were included in the final quantitative analysis. The results showed that the global prevalence of C. parvum in dairy calves was 21.9% (7755/42,890; 95% confidence interval: 19.9-23.9%). C. parvum infection was high in pre-weaned dairy calves (24.9%, 6706/29,753) and diarrhea dairy calves (33.6%, 1637/6077). In countries with low dairy stocking density (<10 cows/farm), the prevalence of C. parvum in dairy calves was also relatively low (15.2%, 1960/16,584). Three subtype families [IIa (72.2%, 2293/3177), IId (27.4%, 872/3177), and IIl (0.4%, 12/3177)] were detected in dairy calves globally from selected studies. C. parvum IIa was the dominant zoonotic subtype. In the IIa subtype family of C. parvum, the proportions of subtypes from high to low (top nine) were IIaA15G2R1 (32.4%, 742/2293), IIaA18G3R1 (11.8%, 271/2293), IIaA13G2R1 (8.2%, 187/2293), IIaA16G1R1 (6.4%, 147/2293), IIaA20G1R1 (3.5%, 81/2293), IIaA16G3R1 (3.4%, 78/2293), IIaA17G2R1 (2.7%, 62/2293), IIaA18G1R1 (2.5%, 58/2293), and IIaA15G1R1 (2.4%, 56/2293). In the IId subtype family of C. parvum, the proportions of subtypes (top four) were IIdA19G1 (36.0%, 314/872), IIdA15G1 (27.3%, 238/872), IIdA20G1 (16.2%, 141/872), and IIdA14G1 (13.0%, 113/872). Furthermore, IId is commonly found in China (771/872). The study results indicated that the IIa subtype family is globally prevalent, while IId is found in Asia, Europe, and Africa and IIl is only found in Europe. Diarrhea in dairy calves is associated with C. parvum infection and a significantly higher prevalence is observed in diarrheic calves. Age and stock density are two significant risk factors in the prevalence of C. parvum in dairy calves. The prevention and control of this zoonosis in dairy calves should receive greater attention, especially in regions with a high degree of intensive dairy farming.

First detection of Blastocystis sp. in migratory whooper swans (Cygnus cygnus) in China.

Blastocystis is a usual intestinal protist that always found in humans and various animals. Currently, the prevalence of Blastocystis in the migratory whooper swan (Cygnus cygnus) is unknown. In our research, we aimed to determine the occurrence, prevalence, subtype distribution and dynamic transmission mechanisms of Blastocystis in the migratory whooper swan in China. We also assessed the zoonotic potential of Blastocystis isolates, as well as possible routes of transmission and impact of this organism on One Health perspective. Fecal samples (n = 770) were collected from whooper swans inhabiting the Sanmenxia Swan Lake National Urban Wetland Park, China. The overall prevalence of Blastocystis was 11.6% (89/770). We identified 9 subtypes of Blastocystis sp., including 5 zoonotic subtypes [ST1 (Cakir et al., 2019 (8)), ST4 (Selma and Karanis, 2011 (4)), ST5 (Stensvold et al., 2009 (1)), ST6 (Fare et al., 2019 (5)) and ST7(58)] and 3 host-specific subtypes [ST10 (Zhao et al., 2018 (7)), ST14 (Tan et al., 2010 (2)), ST23 (Wang et al., 2018 (3)), and ST25 (Stensvold et al., 2009 (1))]. Subtypes ST4, ST5, ST6, ST10, ST14, ST23, and ST25 were first identified in the whooper swan. Among these subtypes, ST23 and ST25 were identified in birds for the first time, indicating that these subtypes are expanding their host range. So far, this is the first research reporting on the prevalence and subtypes distribution of Blastocystis in the migratory whooper swan in China. The findings obtained in this study will provide new insights into the genetic diversity and transmission routes of Blastocystis, and the possible public health concerns posed by this organism.

The global prevalence of parasites in non-biting flies as vectors: a systematic review and meta-analysis.

BACKGROUND: Non-biting flies such as the house fly (Musca domestica), the Australian sheep blowfly (Lucilia cuprina) and the oriental latrine fly (Chrysomya megacephala) may carry many parasites. In the present study, we performed a systematic overview of the different species of parasites carried by non-biting flies, as well as of isolation methods, different geographical distribution, seasonality and risk assessment. METHODS: A meta-analysis was carried out with the aim to review the global prevalence of parasite transmission in non-biting flies. A total sample size of 28,718 non-biting flies reported in studies worldwide satisfied the predetermined selection criteria and was included in the quantitative analysis. RESULTS: The global prevalence of parasites in non-biting flies was 42.5% (95% confidence interval [CI] 31.9-53.2%; n = 15,888/28,718), with the highest prevalence found for non-biting flies in Africa (58.3%; 95% CI 47.4-69.3%; n = 9144/13,366). A total of 43% (95% CI 32.1-54.4%; n = 7234/15,282) of house flies (M. domestica), the fly species considered to be the most closely associated with humans and animals, were found with parasites. The prevalence of parasites in the intestine of non-biting flies was 37.1% (95% CI 22.7-51.5%; n = 1045/3817), which was significantly higher than the prevalence of parasites isolated from the body surface (35.1%; 95% CI 20.8-49.4%; n = 1199/3649; P < 0.01). Of the 27 reported parasites, a total of 20 known zoonotic parasites were identified, with an infection rate of 38.1% (95% CI 28.2-48.0%; n = 13,572/28,494). CONCLUSIONS: This study provides a theoretical basis for the public health and ecological significance of parasites transmitted by non-biting flies.

Molecular characterization and prevalence of Cryptosporidium spp. in sheep and goats in western Inner Mongolia, China.

Cryptosporidium spp. are zoonotic intestinal parasites that infect fish, birds, reptiles and mammals. Cryptosporidium spp. are common cause of diarrhea. In this study, a total of 1032 fecal samples were collected from the rectums of sheep and goats. The samples were analyzed using nested polymerase chain reaction (nested PCR) based on the small subunit ribosomal RNA (SSU rRNA) gene of Cryptosporidium spp. The average infection rate of Cryptosporidium spp. was 2.23% (n = 23), and three Cryptosporidium species were identified, namely Cryptosporidium ubiquitum (8/23), Cryptosporidium andersoni (5/23) and Cryptosporidium xiaoi (10/23). Subtyping of C. ubiquitum and C. xiaoi was carried out by DNA sequence analysis of the 60-kDa glycoprotein (gp60) gene. Eight C. ubiquitum isolates were identified as zoonotic subtype XIIa. Nine C. xiaoi isolates were identified as subtypes XXIIIc (n = 1), XXIIIf (n = 3) and XXIIIg (n = 5). Subtype XXIIIg was first found in Chinese sheep. C. ubiquitum subtype XIIa was found in both sheep and goats, suggesting that sheep and goats are important sources of C. ubiquitum infections.

The global prevalence of Cryptosporidium in sheep: a systematic review and meta-analysis.

Cryptosporidium spp. are important pathogens with some species causing diarrhoea in humans and animals. Sheep are one of the most common potential hosts for various Cryptosporidium spp. The prevalence of Cryptosporidium in sheep globally was evaluated from published information including molecular data via meta-analysis. In total, 126 datasets from 41 countries were included for final quantitative analysis. Sheep aged <3 months had a significantly higher prevalence (27.8%; 3284/11 938) than those at the age of 3­12 and >12 months. The prevalence of Cryptosporidium in sheep with diarrhoea of 35.4% (844/1915) was higher than in sheep that did not show diarrhoea (11.3%; 176/1691). Fourteen Cryptosporidium species/genotypes were detected in sheep globally. The proportion of subgenotype family XIIa of Cryptosporidium ubiquitum was 90.0% (216/240); the proportions of subgenotypes IIdA20G1 and IIaA15G2R1 of Cryptosporidium parvum were 15.4% (62/402) and 19.7% (79/402). The results indicate that C. parvum is the dominant species in Europe while Cryptosporidium xiaoi is the dominant species in Oceania, Asia and Africa and C. ubiquitum is the dominant species in North America and South America. Subgenotype family IIa of C. parvum is particularly widespread among sheep worldwide. The results highlight the role of sheep as a reservoir host for zoonotic cryptosporidia and the need for further study of prevalence, transmission and control of this pathogen in sheep.