Prevalence of and risk factors associated with Cryptosporidium infection in an underdeveloped rural community of southwest China

Prevalence and risk estimates of Cryptosporidium oocysts infection associated with consumption of raw-eaten vegetables in Maiduguri metropolis LGAs, Northeast Nigeria

Cryptosporidium is one of the most important protozoan parasitic pathogens, and it is a common cause of diarrhoea in humans, domestic animals, and wild vertebrates and has serious public health threats. A cross-sectional study was designed to determine the prevalence of Cryptosporidium oocysts in raw-eaten vegetables in Maiduguri Metropolitan Council (MMC) and Jere Local Government Areas (LGAs). A total of 400 samples were collected from four (4) different locations, namely Tashan Bama, Gomboru, and Monday Markets (n = 100), while fifty (n = 50) each from 202-Vegetable-Vendors and Unimaid Commercials. A total of 16 visits were conducted in all the sampling areas (twenty-five samples per visit). The Cryptosporidium oocysts were detected using the Modified Ziehl-Neelsen Staining Technique. The locations, sources, and types of raw-eaten vegetables were also assessed. The oocysts were confirmed (100×) as bright pink spherules. Data generated were analyzed using IBM-SPSS V23.0, and p ≤ 0.05 was considered significant. Out of the total samples (n = 400) analyzed, cabbage appeared to have the highest number of 10 (12.5%) of Cryptosporidium oocysts detected, while Tomato and garden egg had 9 (11.3%) and 1 (1.2%), respectively. There was a statistically significant association (χ2 = 12.5, P = 0.014) between the presence of Cryptosporidium oocysts in raw-eaten vegetables and vegetable types. Among the sources of the vegetables sampled, Alau had the highest number of Cryptosporidium oocysts, 15 (12.5%), followed by Kilari-Abdullahi and Zabarmari sources with 4 (10.0%) and 4 (5.0%), respectively. However, Jetete appeared to have the least number 2 (2.5%) of oocysts, and there was a statistically significant association (χ2= 10.4, P = 0.034) between the presence of Cryptosporidium oocysts and the sources of vegetables and fruits. The study concludes that the raw-eaten vegetables sampled from Maiduguri Metropolis were contaminated with Cryptosporidium oocysts. The study recommends that all raw-eaten vegetables should be from cleaned sources and washed before consumption. Consumers should be enlightened on the hygienic measures in the food chain in line with the Hazard Analysis and Critical Control Points (HACCP) principles.

Distribution of bacteriologically positive and bacteriologically negative pulmonary tuberculosis in Northwest China: spatiotemporal analysis

Pulmonary tuberculosis (PTB) is a major health issue in Northwest China. Most previous studies on the spatiotemporal patterns of PTB considered all PTB cases as a whole; they did not distinguish notified bacteriologically positive PTB (BP-PTB) and notified bacteriologically negative PTB (BN-PTB). Thus, the spatiotemporal characteristics of notified BP-PTB and BN-PTB are still unclear. A retrospective county-level spatial epidemiological study (2011-2018) was conducted in Shaanxi, Northwest China. In total, 44,894 BP-PTB cases were notified, with an average annual incidence rate of 14.80 per 100,000 persons between 2011 and 2018. Global Moran's I values for notified BP-PTB ranged from 0.19 to 0.49 (P < 0.001). Anselin's local Moran's I analysis showed that the high-high (HH) cluster for notified BP-PTB incidence was mainly located in the southernmost region. The primary spatiotemporal cluster for notified BP-PTB (LLR = 612.52, RR = 1.77, P < 0.001) occurred in the central region of the Guanzhong Plain in 2011. In total, 116,447 BN-PTB cases were notified, with an average annual incidence rate of 38.38 per 100,000 persons between 2011 and 2018. Global Moran's I values for notified BN-PTB ranged from 0.39 to 0.69 (P < 0.001). The HH clusters of notified BN-PTB were mainly located in the north between 2011 and 2014 and in the south after 2015. The primary spatiotemporal cluster for notified BN-PTB (LLR = 1084.59, RR = 1.85, P < 0.001) occurred in the mountainous areas of the southernmost region from 2014 to 2017. Spatiotemporal clustering of BP-PTB and BN-PTB was detected in the poverty-stricken mountainous areas of Shaanxi, Northwest China. Our study provides evidence for intensifying PTB control activities in these geographical clusters.

Benefits and Risks of Smallholder Livestock Production on Child Nutrition in Low- and Middle-Income Countries

Livestock production may improve nutritional outcomes of pregnant women and children by increasing household income, availability of nutrient-dense foods, and women's empowerment. Nevertheless, the relationship is complex, and the nutritional status of children may be impaired by presence of or proximity to livestock and their pathogens. In this paper, we review the benefits and risks of livestock production on child nutrition. Evidence supports the nutritional benefits of livestock farming through income, production, and women's empowerment. Increasing animal source food consumption requires a combination of efforts, including improved animal management so that herd size is adequate to meet household income needs and consumption and addressing sociocultural and gendered norms. Evidence supports the inclusion of behavior change communication strategies into livestock production interventions to facilitate the sustainability of nutritional benefits over time, particularly interventions that engage women and foster dimensions of women's empowerment. In evaluating the risks of livestock production, evidence indicates that a broad range of enteric pathogens may chronically infect the intestines of children and, in combination with dietary deficits, may cause environmental enteric dysfunction (EED), a chronic inflammation of the gut. Some of the most important pathogens associated with EED are zoonotic in nature with livestock as their main reservoir. Very few studies have aimed to understand which livestock species contribute most to colonization with these pathogens, or how to reduce transmission. Control at the point of exposure has been investigated in a few studies, but much less effort has been spent on improving animal husbandry practices, which may have additional benefits. There is an urgent need for dedicated and long-term research to understand which livestock species contribute most to exposure of young children to zoonotic enteric pathogens, to test the potential of a wide range of intervention methods, to assess their effectiveness in randomized trials, and to assure their broad adaptation and sustainability. This review highlights the benefits and risks of livestock production on child nutrition. In addition to identifying research gaps, findings support inclusion of poor gut health as an immediate determinant of child undernutrition, expanding the established UNICEF framework which includes only inadequate diet and disease.

Risk Evaluation of Pathogenic Intestinal Protozoa Infection Among Laboratory Macaques, Animal Facility Workers, and Nearby Villagers From One Health Perspective

Background: Previous epidemiological studies have confirmed non-human primates (NHPs) as reservoirs for Cryptosporidium spp. , Giardia intestinalis, and Enterocytozoon bieneusi. It highlights the possibility of interspecies transmission between humans and macaques in laboratory animal facilities. This study aimed to investigate the prevalence of pathogenic intestinal protozoan infections in macaques and humans and to determine the risk of cross-species transmission from One Health view.

Materials and Methods: A total of 360 fecal samples, including 310 from the four Macaca mulatta groups, 25 from the facility workers in a laboratory animal facility, and 25 from the villagers nearby in Yongfu country, southeast China, were collected. Nested PCR assays were done for detecting protozoan pathogens from all the specimens. Furthermore, potential risk factors (gender, age, and direct contact) on the occurrence of intestinal protozoa infection among different sub-groups were evaluated. A phylogenetic and haplotype network analysis was conducted to examine the genetic structure and shared patterns of E. bieneusi and Cyclospora cayetanensis.

Results: The pathogenic intestinal protozoa were detected in both human and macaque fecal samples. A total of 134 (37.2%) samples were tested positive, which included 113 (36.4%) macaques, 14 (56.0%) facility workers, and 7 (28.0%) villagers, respectively. There was no significant difference in four intestinal protozoa infections between facility workers and villagers (χ² = 2.4, P > 0.05). However, the positive rate of pathogenic intestinal protozoa in the facility workers, who had direct contact with macaques, was significantly higher [odds ratio (OR) = 0.31, 95% confidence interval (CI): 0.09–1.00, P < 0.05).Thirty-three ITS genotypes of E. bieneusi were identified, including five known genotypes (PigEBITS7, Peru8, Henan V, D, and CM1) and six novel genotypes (MEB1–6). Seven haplotypes were identified in the network analysis from C. cayetanensis-positive samples. Meanwhile, a phylogenetic and haplotype analysis confirmed the presence of zoonotic subtypes in NHPs and humans.

Conclusion: The data collected from this study confirmed a high prevalence of intestinal protozoan infection in humans and macaques. These results warrant workers of such facilities and residents to limit contact with infected animals in order to minimize related health risks. The need for comprehensive strategies to mitigate the risk of zoonotic transmission, especially from a One Health perspective, is recommended.

Chronic urban hotspots and agricultural drainage drive microbial pollution of karst water resources in rural developing regions

Contamination of surface and groundwater systems with human and animal faecal matter leads to exposure of reliant populations to disease causing micro-organisms. This exposure route remains a major cause of infection and mortality in developing countries, particularly rural regions. To meet the UN's sustainable development goal 6: Ensure availability and sustainable management of water and sanitation for all, we need to identify the key controls on faecal contamination across relevant settings. We conducted a high-resolution spatial study of E. coli concentration in catchment drainage waters over 6 months in a mixed land-use catchment in the extensive karst region extending across impoverished southwest China. Using a mixed effects modelling framework, we tested how land-use, karst hydrology, antecedent meteorological conditions, agricultural cycles, hydrochemistry, and position in the catchment system affected E. coli concentrations. Land-use was the best predictor of faecal contamination levels. Sites in urban areas were chronically highly contaminated, but water draining from agricultural land was also consistently contaminated and there was a catchment wide pulse of higher E. coli concentrations, turbidity, and discharge during paddy field drainage. E. coli concentration increased with increasing antecedent rainfall across all land-use types and compartments of the karst hydrological system (underground and surface waters), but decreased with increasing pH. This is interpreted to be a result of processes affecting pH, such as water residence time, rather than the direct effect of pH on E. coli survival. Improved containment and treatment of human waste in areas of higher population density would likely reduce contamination hotspots, and further research is needed to identify the nature and distribution of sources in agricultural land.

Cryptosporidiosis in HIV-positive patients and related risk factors: A systematic review and meta-analysis

Cryptosporidium is one of the major causes of diarrhea in HIV-positive patients. The aim of this study is to systematically review and meta-analyze the prevalence of Cryptosporidium in these patients. PubMed, Science Direct, Google Scholar, Web of Science, Cochrane and Ovid databases were searched for relevant studies dating from the period of 1 January 2000 to 31 December 2017. Data extraction for the included studies was performed independently by two authors. The overall pooled prevalence was calculated and subgroup analysis was performed on diagnostic methods, geographical distribution and study population. Meta-regression was performed on the year of publication, proportion of patients with diarrhea, and proportion of patients with CD4 < 200 cells/mL. One hundred and sixty-one studies and 51,123 HIV-positive participants were included. The overall pooled prevalence of Cryptosporidium infection in HIV-positive patients was 11.2% (CI95%: 9.4%–13.0%). The pooled prevalence was estimated to be 10.0% (CI95%: 8.4%–11.8%) using staining methods, 13.5% (CI95%: 8.9%–19.8%) using molecular methods, and 26.3% (CI95%: 15.0%–42.0%) using antigen detection methods. The prevalence of Cryptosporidium in HIV patients was significantly associated with the country of study. Also, there were statistical differences between the diarrhea, CD4 < 200 cells/mL, and antiretroviral therapy risk factors with Cryptosporidiosis. Thus, Cryptosporidium is a common infection in HIV-positive patients, and safe water and hand-hygiene should be implemented to prevent cryptosporidiosis occurrence in these patients.

The role of education in maternal depressive symptoms among different ethnic groups: A cross-sectional study in rural western China

OBJECTIVE

To estimate the maternal depressive symptoms (MDS) rates in different ethnic groups, and to explore possible reasons especially the role of education for its ethnic differences.

METHODS

A community-based cross-sectional survey was conducted in 20 rural counties of 8 provinces in western China. The possible influencing factors of MDS were collected. The Edinburgh Postpartum Depression Scale (EPDS) was used to assess MDS. Univariate and multivariate logistic regression models were used to analyze the risk factors of MDS. Two multivariate logistic regression models that separately containing and not containing the factor of educational level were used to explore the role of education in the ethnic differences of MDS.

RESULTS

A total of 3,163 mothers were included in the analysis, and the MDS rate was 15.6%. In multivariate analysis, educational level of primary school and below (adjOR1: 1.47, 95%CI: 1.07-2.03), delivery at home (adjOR1: 1.66, 95%CI: 1.11-2.47) and diarrhea of youngest child in the past two weeks (adjOR1: 1.31, 95%CI: 1.03-1.67) remained as independent predictors of MDS after adjusting all the factors significant in univariate analysis. If educational level was not adjusted in above multivariate model, women from Yi ethnic group (adjOR2: 1.39, 95%CI: 1.03-1.89) would additionally become significant.

LIMITATIONS

EPDS is a screening tool and some possible risk factors for MDS were not included.

CONCLUSION

The ethnic differences in MDS were largely due to the ethnic differences in educational level. To reduce the high risk of MDS among Yi mothers, further popularizing nine-year compulsory education could be effective.

First report of Cryptosporidium viatorum and Cryptosporidium occultus in humans in China, and of the unique novel C. viatorum subtype XVaA3h

BACKGROUND

Cryptosporidium is a genus of common intestinal protozoa, members of which cause diarrhea in a wide variety of hosts. Previous studies on Cryptosporidium in China have mainly focused on diarrhea sufferers, children, and immunodeficient individuals such as HIV/AIDS patients. However, the epidemiological characteristics of Cryptosporidium in the population in rural areas remain unclear. Herein, we investigated the prevalence of, and risk factors for, Cryptosporidium in rural areas of Binyang County, Guangxi Zhuang Autonomous Region, China, and genetically characterized the Cryptosporidium isolates we obtained.

METHODS

From August to December 2016, two villages in Binyang County, Guangxi, were sampled using a random cluster sampling method. Fresh fecal samples were collected from all eligible residents (residence time > 6 months). Molecular characterization of Cryptosporidium was carried out based on its SSU rRNA, gp60, actin and hsp70 gene sequences. Fisher's exact test were conducted to assess the risk factors for Cryptosporidium infection.

RESULTS

A total of 400 fecal samples were collected from 195 males (48.8%) and 205 females (51.2%). Two samples (0.5%) were positive for Cryptosporidium and were identified as C. viatorum and C. occultus respectively. Moreover, a new C. viatorum subtype XVaA3h was identified based on the sequence of the gp 60 gene.

CONCLUSIONS

To our knowledge, this is the first report of C. viatorum and C. occultus infections in humans in China and of C. viatorum subtype XVaA3h. The findings provide important information on the prevalence of Cryptosporidium in the Chinese population, and expand the range of Cryptosporidium species known to infect people in China.

Frequency and Molecular Identification of Cryptosporidium Species among Immunocompromised Patients Referred to Hospitals, Central Iran, 2015-16

BACKGROUND

The purpose of this study was to determine the prevalence and genotype of Cryptosporidium spp. in different groups of immunocompromised patients admitted to the referral hospitals in center of Iran during 2015-2016.

METHODS

This cross-sectional study was conducted on 346 immunocompromised patients (HIV⁺/AIDS, Lymphoma, Leukemia and organ transplants) in referred hospitals from central parts of Iran including Isfahan, Markazi, Yazd and Chaharmahale Bakhtiari provinces. Stool samples were analyzed for Cryptosporidium species, modified Ziehl-Neelsen staining techniques followed by the semi-nested PCR and DNA sequencing methods.

RESULTS

The total rate of Cryptosporidium spp. was 3.46% (12/346) in the patients, however, the prevalence of the parasite, was 4.6% (4/87) in HIV⁺/AIDS patients, 3.6% (6/168) in patients with blood malignancy and 2.1% (2/91) in organ transplant recipients. The SSU rRNA gene of Cryptosporidium spp. in all microscopic-positive samples was effectively amplified by the semi-nested PCR and DNA sequences, exposed the existence of two Cryptosporidium species, including C. hominis 91.6% (11/12) and C. parvum 8.3% (1/12).

CONCLUSION

The predominance of C. hominis in the present study may be certifies the importance of anthroponotic transmission of cryptosporidiosis in center of Iran.

Evaluation of prevalence and risk factors associated with Cryptosporidium infection in rural population of district Buner, Pakistan

BACKGROUND

Cryptosporidium spp are important intestinal protozoan parasites that cause diarrhea in humans, domestic and wild animals. Its infection remains a main public health concern however, the epidemics in human being is still unclear, particularly in developing countries. There are several factors that may enhance the spreading of this parasite in human population especially in young children.

METHODOLOGY

A questionnaire was designed to obtain the demographic and clinical data from the participants. A total of 425 stool samples were collected from suspected children (aged 3-10 years) in different hospitals and villages. The initial screening was performed with modified Ziehl Neelsen (mZN) staining technique followed by polymerase chain reaction (PCR). Several potential risk factors were also assessed through the obtained information from suspected individuals.

RESULTS

Out of all 425 collected samples, 127 were observed positive by mZN with a prevalence of 29.88% (127/425). The 127 mZN positive samples together with 50 mZN negative samples were processed for molecular analysis through PCR assay. Among them, 71 out of 127 mZN positive samples and 4 out of 50 mZN negative samples were found positive by PCR. The molecular analysis showed that Cryptosporidium parvum was the main cause of infection in children. The results revealed that individuals exposed to diarrhea were more likely to be infected with Cryptosporidium infection while several environmental factors may also play a key role in spreading of this parasite.

CONCLUSIONS/SIGNIFICANCE OF THE STUDY

The current high prevalence of Cryptosporidium infection may be due to the lack of awareness and routine based testing in identification of this parasite in District Buner. Further studies are required to determine the importance of Cryptosporidium infection in this area as well as across the country and to find out the possible risk factors that may be associated with the occurrence of this protozoan. There is, however, an urgent need for laboratory-based observational studies to develop a more dynamic estimate of the cryptosporidial disease burden in the region.

Risk Factors and Spatial Clusters of Cryptosporidium Infection among School-Age Children in a Rural Region of Eastern China

The epidemiological features of Cryptosporidium infection among school-age children in China still remain unclear. Hereby, a cross-sectional study of 1637 children aged 3–9 years was designed to investigate the risk factors and spatial clusters of Cryptosporidium infection in a rural region of Eastern China. Stool specimens collected from participants were examined using the auramine-phenol and modified acid-fast staining. Univariable and multivariable analyses were performed to identify the risk factors of Cryptospordium infection. The spatial clusters were analyzed by a discrete Poisson model using SaTScan software. Our results showed that the overall prevalence of Cryptosporidium infection was 11‰ in the research region. At the age of 3–6 years (odds ratios (OR) = 3.072, 95% confidence intervals (CI): 1.001–9.427), not washing hands before eating and after defecation (OR = 3.003, 95% CI: 1.060–8.511) were recognized as risk factors. Furthermore, a high-risk spatial cluster (relative risk = 4.220, p = 0.025) was identified. These findings call for effective sustainable interventions including family and school-based hygienic education to reduce the prevalence of Cryptosporidium infection. Therefore, an early warning system based spatiotemporal models with risk factors is required to further improve the effectiveness and efficiency of cryptosporidiosis control in the future.

Detection of Cryptosporidium spp. in Diarrheic Immunocompetent Patients in Beni-Suef, Egypt: Insight into Epidemiology and Diagnosis

Cryptosporidium species is an important cause of gastrointestinal infections globally. This study aimed to shed light on its role in diarrheic immunocompetent patients in Beni-Suef, Egypt and to compare three diagnostic methods. Two hundred diarrheic patients, 37±16.8 year old, were enrolled. Stool samples were examined by light microscopy, using modified Ziehl-Neelsen stain (MZN) for Cryptosporidium spp. oocysts. Coproantigens were detected by sandwich ELISA. DNA molecular diagnosis was done by nested PCR. PCR yielded the highest detection rates (21.0%), compared to ELISA (12.5%) and MZN staining method (9.5%). The higher infection rates were in 20–40 year-old group, followed by 40–60 year-old. Association between epidemiologic factors was statistically not significant; positivity and gender, clinical manifestations, residence, source or water, or contact with animals. Cryptosporidiosis is an important enteric parasitic infection in Beni-Suef and PCR remains the gold standard for diagnosis.

Presence and molecular characterization of Cryptosporidium and Giardia in recreational lake water in Tianjin, China: a preliminary study

Little is known about the occurrence of Cryptosporidium and Giardia in recreational water in China. A total of 52 samples were collected from recreational lakes in Tianjin during a high-occurrence season (June-October) for the waterborne cryptosporidiosis and giardiasis, and the occurrence and genotypes of Cryptosporidium and Giardia were investigated. The results showed that 82.7% (43) and 98.1% (51) of samples were positive for Cryptosporidium oocyst and Giardia cysts, respectively. The mean concentration of parasites was 3.65 oocysts/10 L and 12.58 cysts/10 L, respectively. Molecular characterization revealed that the presence of Cryptosporidium parvum, C. andersoni, C. hominis, C. meleagridis, C. fragile, C. ubiquitum, and Giardia lamblia assemblage A, B and D. The protozoan contamination in the studied lakes may originate from animal feces on ground, which was washed into the lake by stormwater runoff. Nevertheless, there is a potential risk of infection during recreational activities in the lake because the dominant detected protozoan genotypes are common human pathogens. Moreover, microbial indicators analysis does not adequately indicate the protozoan contamination in recreational water. The information from this study will be valuable for future protozoan source tracking, and any further control interventions against Cryptosporidium and/or Giardia infection associated with recreational water.

Human Intestinal Microbiota: Interaction Between Parasites and the Host Immune Response

The human gut is a highly complex ecosystem with an extensive microbial community, and the influence of the intestinal microbiota reaches the entire host organism. For example, the microbiome regulates fat storage, stimulates or renews epithelial cells, and influences the development and maturation of the brain and the immune system. Intestinal microbes can protect against infection by pathogenic bacteria, viruses, fungi and parasites. Hence, the maintenance of homeostasis between the gut microbiota and the rest of the body is crucial for health, with dysbiosis affecting disease. This review focuses on intestinal protozoa, especially those still representing a public health problem in Mexico, and their interactions with the microbiome and the host. The decrease in prevalence of intestinal helminthes in humans left a vacant ecological niche that was quickly occupied by protozoa. Although the mechanisms governing the interaction between intestinal microbiota and protozoa are poorly understood, it is known that the composition of the intestinal bacterial populations modulates the progression of protozoan infection and the outcome of parasitic disease. Most reports on the complex interactions between intestinal bacteria, protozoa and the immune system emphasize the protective role of the microbiota against protozoan infection. Insights into such protection may facilitate the manipulation of microbiota components to prevent and treat intestinal protozoan infections. Here we discuss recent findings about the immunoregulatory effect of intestinal microbiota with regards to intestinal colonization by protozoa, focusing on infections by Entamoeba histolytica, Blastocystis spp, Giardia duodenalis, Toxoplasma gondii and Cryptosporidium parvum. The possible consequences of the microbiota on parasitic, allergic and autoimmune disorders are also considered.