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170 result(s) for "Entamoebiasis - epidemiology"
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Effects of Water, Sanitation, Handwashing, and Nutritional Interventions on Child Enteric Protozoan Infections in Rural Bangladesh: A Cluster-Randomized Controlled Trial
The trial found that individual handwashing and sanitation interventions significantly reduced childhood Giardia infections. Combined interventions provided no additional benefit. To reduce Giardia infection, individual interventions may be more feasible and cost-effective than combined interventions in similar rural, low-income settings. Abstract Background We evaluated effects of individual and combined water, sanitation, handwashing (WSH), and nutritional interventions on protozoan infections in children. Methods We randomized geographical clusters of pregnant women in rural Bangladesh into chlorinated drinking water, hygienic sanitation, handwashing, nutrition, combined WSH, nutrition plus WSH (N+WSH), or control arms. Participants were not masked. After approximately 2.5 years of intervention, we measured Giardia, Cryptosporidium, and Entamoeba histolytica prevalence and infection intensity by multiplex real-time polymerase chain reaction of child stool. Analysis was intention-to-treat. Results Between May 2012 and July 2013, we randomized 5551 pregnant women. At follow-up, among 4102 available women, we enrolled 6694 children into the protozoan assessment. We analyzed stool from 5933 children (aged ~31 months) for protozoan infections. Compared with 35.5% prevalence among controls, Giardia infection prevalence was lower in the sanitation (26.5%; prevalence ratio [PR], 0.75 [95% confidence interval {CI}, .64-.88]), handwashing (28.2%; PR, 0.80 [95% CI, .66-.96]), WSH (29.7%; PR, 0.83 [95% CI, .72-.96]), and N+WSH (26.7%; PR, 0.75 [95% CI, .64-.88]) arms. Water and nutrition interventions had no effect. Low prevalence of E. histolytica and Cryptosporidium (<2%) resulted in imprecise effect estimates. Conclusions Individual handwashing and hygienic sanitation interventions significantly reduced childhood Giardia infections, and there were no effects of chlorinated drinking water and nutrition improvements in this context. Combined WSH interventions provided no additional benefit. To reduce Giardia infection, individual WSH interventions may be more feasible and cost-effective than combined interventions in similar rural, low-income settings. Clinical Trials Registration NCT01590095.
Molecular and descriptive epidemiology of intestinal protozoan parasites of children and their pets in Cauca, Colombia: a cross-sectional study
Background Parasitic infections, particularly those caused by protozoa, represent a considerable public health problem in developing countries. Blastocystis , Giardia duodenalis , Cryptosporidium spp. and the Entamoeba complex ( Entamoeba histolytica, Entamoeba dispar and Entamoeba moshkovskii) are the most common etiological causes of intestinal parasitic infections. Methods We carried out a descriptive cross-sectional study in school-age children attending a daycare institution in commune eight of Popayán, Cauca (Southwest Colombia). A total of 266 fecal samples were collected (258 from children and eight from pets). Blastocystis , G. duodenalis , Cryptosporidium spp. and the Entamoeba complex were identified by microscopy, quantitative real-time PCR (qPCR) and conventional PCR. The concordance of qPCR and microscopy was assessed using the Kappa index. Molecular characterization was conducted to identify Blastocystis subtypes (18S), G. duodenalis assemblages ( tpi and gdh ) and Cryptosporidium species/subtypes (18S and GP60). Potential associations between intestinal parasitism and sociodemographic factors were examined using bivariate analyses. Results A total of 258 fecal samples from children were analyzed by microscopy and 255 samples were analyzed by qPCR. The prevalence of Blastocystis was between 25.19% (microscopy) and 39.22% (qPCR), that of G. duodenalis was between 8.14% (microscopy) and 10.59% (qPCR), that of Cryptosporidium spp. was estimated at 9.8% (qPCR), and that of the Entamoeba complex was between 0.39% (conventional PCR) and 0.78% (microscopy). The concordance between microscopy and qPCR was very low. Blastocystis ST1 (alleles 4, 8, and 80), ST2 (alleles 11, 12, and 15), ST3 (alleles 31, 34, 36, 38,57, and 151), and ST4 (alleles 42 and 91), G. duodenalis assemblages AII, BIII, BIV and D, C. parvum subtype IIa and C. hominis subtype IbA9G3R2 were identified. The only identified member of the Entamoeba complex corresponded to E. histolytica . No statistically significant association was identified between parasitic infection and any sociodemographic variable. Conclusion This study revealed the usefulness of molecular methods to depict the transmission dynamics of parasitic protozoa in southwest Colombia. The presence of some of these protozoa in domestic animals may be involved in their transmission.
The history of entamoebiasis
This review article summarizes the history of amoebic dysentery (entamoebiasis) caused by Entamoeba histolytica . Initially, Entamoeba species were thought to be the most primitive extant eukaryotes, but more recent research revealed that they emerged relatively late in evolutionary history. Paleoparasitological data suggest that E. histolytica has been a parasite of humans since ancient times and was probably spread throughout the world by man during early human migration. By the end of the 19th century, it was established that E. histolytica was the etiological agent of amoebic dysentery and liver abscess. The issue over pathogenic and non-pathogenic strains of E. histolytica was resolved in the 1980s by the discovery of the morphologically indistinguishable harmless sister species Entamoeba dispar . Being mainly a disease of tropical and subtropical low-income countries, entamoebiasis cases have increased among travellers and immigrants arriving from endemic regions in recent years.
Prevalence and molecular characterization of Entamoeba moshkovskii in diarrheal patients from Eastern India
Importance of the amphizoic amoeba Entamoeba moshkovskii is increasing in the study of amoebiasis as a common human pathogen in some settings. Limited studies are found on the genetic and phylogenetic characterization of E. moshkovskii from India; hence remain largely unknown. In this study, we determined the prevalence and characterized the E. moshkovskii isolates in eastern India. A three-year systemic surveillance study among a total of 6051 diarrhoeal patients from ID Hospital and BC Roy Hospital, Kolkata was conducted for E. moshkovskii detection via a nested PCR system targeting 18S rRNA locus. The outer primer set detected the genus Entamoeba and the inner primer pair identified the E. moshkovskii species. The 18S rRNA locus of the positive samples was sequenced. Genetic and phylogenetic structures were determined using DnaSP.v5 and MEGA-X. GraphPad Prism (v.8.4.2), CA, USA was used to analyze the statistical data. 4.84% (95%CI = 0.0433-0.0541) samples were positive for Entamoeba spp and 3.12% (95%CI = 0.027-0.036) were infected with E. moshkovskii. E. moshkovskii infection was significantly associated with age groups (X2 = 26.01, P<0.0001) but not with gender (Fisher's exact test = 0.2548, P<0.05). A unique seasonal pattern was found for E. moshkovskii infection. Additionally, 46.56% (95%CI = 0.396-0.537) were sole E. moshkovskii infections and significantly associated with diarrheal incidence (X2 = 335.5,df = 9; P<0.0001). Sequencing revealed that the local E. moshkovskii strains were 99.59%-100% identical to the prototype (GenBank: KP722605.1). The study found certain SNPs that showed a correlation with clinical features, but it is not necessarily indicative of direct control over pathogenicity. However, SNPs in the 18S rRNA gene could impact the biology of the amoeba and serve as a useful phylogenetic marker for identifying pathogenic E. moshkovskii isolates. Neutrality tests of different coinfected subgroups indicated deviations from neutrality and implied population expansion after a bottleneck event or a selective sweep and/or purifying selection in co-infected subgroups. The majority of FST values of different coinfected subgroups were <0.25, indicating low to moderate genetic differentiation within the subgroups of this geographical area. The findings reveal the epidemiological significance of E. moshkovskii infection in Eastern India as the first report in this geographical area and expose this species as a possible emerging enteric pathogen in India. Our findings provide useful knowledge for further research and the development of future control strategies against E. moshkovskii.
Entamoeba Species in South Africa
Three species of Entamoeba were common in South Africa: E. dispar, E. histolytica, and the recently described E. bangladeshi. In E. histolytica–positive samples, changes in both parasite and P. copri levels were associated with alterations in gastrointestinal status. Abstract Background Diarrhea is frequent in communities without clean water, which include low-income South African populations in Giyani and Pretoria. In these populations, the amount of diarrhea caused by Entamoeba histolytica, inclusive of all ages, sexes, and human immunodeficiency virus status, is uncertain. Infection with E. histolytica can modulate the host microbiota, and a key species indicative of this is the Prevotella copri pathobiont. Methods A cross-sectional study of patients attending gastroenterology clinics was conducted to determine the frequency and burden of 4 Entamoeba species and P. copri. Results Entamoeba species were present in 27% of patients (129/484), with E. histolytica detected in 8.5% (41), E. dispar in 8% (38), E. bangladeshi in 4.75% (23), and E. moshkovskii in 0%. This is the first description of E. bangladeshi outside Bangladesh. In E. histolytica–positive samples, the levels of both the parasite and P. copri were lower in nondiarrheal samples, validating the results of a study in Bangladesh (P = .0034). By contrast, in E. histolytica–negative samples positive for either of the nonpathogenic species E. dispar or E. bangladeshi, neither P. copri nor Entamoeba levels were linked to gastrointestinal status. Conclusions Nonmorphologic identification of this parasite is essential. In South Africa, 3 morphologically identical Entamoeba were common, but only E. histolytica was linked to both disease and changes in the microbiota.
Entamoeba histolytica infection in men who have sex with men
Entamoeba histolytica infection (amoebiasis) is the second leading cause of death from parasitic diseases. Epidemiological studies from developed countries have reported an increasing prevalence of amoebiasis and of invasive infections, such as amoebic colitis, among men who have sex with men (MSM) who engage in oral–anal sex. Although most infections with E histolytica are asymptomatic, clinical manifestations of invasive amoebiasis mainly include amoebic colitis and amoebic liver abscess, which are associated with substantial morbidity and medical cost. Laboratory diagnosis of amoebiasis should be based on detection of E histolytica by use of tests with high sensitivity and specificity, such as specific amoebic-antigen or PCR-based assays. Microscopy used in routine clinical laboratories is not sensitive or specific enough for detection of E histolytica. Metronidazole or tinidazole remains the mainstay of treatment for invasive amoebiasis, followed by treatment with luminal agents to prevent relapse and transmission of E histolytica to sexual partners or close contacts.
Molecular characterization of Giardia duodenalis, Cryptosporidium spp., and Entamoeba spp. infecting domestic and feral/stray cats in Jordan
This study aimed to carry out a molecular screening for the presence of Giardia , Cryptosporidium , and/or Entamoeba in the feces of pet and stray/feral cats in Jordan. G. duodenalis was found in 27.9% (95% CI, 23.2–32.9) of the 348 sampled cats overall; E. histolytica was found in only 0.6% (95% CI, 0.1–2.1) of the cats, while none of the sampled cats had Cryptosporidium infections. The infection rate of G. duodenalis among indoor cats (32.3%) did not differ significantly from that among outdoor cats (24.1%). There were significantly more infections ( p  = 0.0004) geographically in the cold semiarid areas (67%) than in the cold desert areas (24%). Multilocus sequence typing analysis of amplicons based on the bg , tpi , and gdh genes revealed that the majority of G. duodenalis infections were zoonotic assemblage B (65.9%; 64 of 97 positive samples); followed by feline-specific assemblage F (18.5%, 18/97); cattle-specific assemblage E (5.2%, 5/97); and then assemblage C that was shared with canids (1.0%; 1/97). Within Giardia isolates, a substitution mutation (A/G) was found at position 297 of the complete protein coding sequence (cds) of tpi -assemblage B, which may represent a new spreading mutation within this gene among the cat population in Jordan. The results of the present study suggest that close human-cat interactions could play a role in zoonotic transmission of Giardia , but further research is needed to determine the possible contribution of cats to the transmission of other protozoa to humans.
Epidemiology of clinically relevant Entamoeba spp. (E. histolytica/dispar/moshkovskii/bangladeshi): A cross sectional study from North India
Entamoeba infections have major impact on millions of the people worldwide. Entamoeba histolytica has long been accepted as the only pathogenic species. However, recent reports of other Entamoeba spp. in symptomatic cases have raised questions on their pathogenicity. Total 474 stool samples and 125 liver aspirates from patients with intestinal and extra intestinal manifestations and from community were included. Sewage samples from the hospital and the city were also included. Microscopic examination and molecular detection were performed to detect presence of E. histolytica/ dispar/ moshkovskii/ bangladeshi. The associated demographic and socioeconomic factors were statistically analyzed with the presence of Entamoeba. Microscopy detected Entamoeba spp. in 5.4% stool and 6.4% liver aspirate samples. Through nested multiplex PCR, prevalence of Entamoeba spp. in intestinal and extra-intestinal cases was 6.6% (20/301) and 86.4% (108/125) respectively and in asymptomatic population was 10.5% (13/123). Sewage samples did not show presence of any Entamoeba spp. Uneducated subjects, low economic conditions, untreated drinking water, consumption of raw vegetables and habit of not washing hands before meals were significantly associated with presence of Entamoeba spp. E. histolytica still remains the only Entamoeba spp. in invasive extra intestinal infections. E. dispar was detected in both asymptomatic and symptomatic intestinal infections. Routine identification of Entamoeba spp. should incorporate PCR based detection methods.
Genetic characterization of the Entamoeba moshkovskii population based on different potential genetic markers
Entamoeba moshkovskii, according to recent studies, appears to exert a more significant impact on diarrhoeal infections than previously believed. The efficient identification and genetic characterization of E. moshkovskii isolates from endemic areas worldwide are crucial for understanding the impact of parasite genomes on amoebic infections. In this study, we employed a multilocus sequence typing system to characterize E. moshkovskii isolates, with the aim of assessing the role of genetic variation in the pathogenic potential of E. moshkovskii. We incorporated 3 potential genetic markers: KERP1, a protein rich in lysine and glutamic acid; amoebapore C (apc) and chitinase. Sequencing was attempted for all target loci in 68 positive E. moshkovskii samples, and successfully sequenced a total of 33 samples for all 3 loci. The analysis revealed 17 distinct genotypes, labelled M1–M17, across the tested samples when combining all loci. Notably, genotype M1 demonstrated a statistically significant association with diarrhoeal incidence within E. moshkovskii infection (P = 0.0394). This suggests that M1 may represent a pathogenic strain with the highest potential for causing diarrhoeal symptoms. Additionally, we have identified a few single-nucleotide polymorphisms in the studied loci that can be utilized as genetic markers for recognizing the most potentially pathogenic E. moshkovskii isolates. In our genetic diversity study, the apc locus demonstrated the highest Hd value and π value, indicating its pivotal role in reflecting the evolutionary history and adaptation of the E. moshkovskii population. Furthermore, analyses of linkage disequilibrium and recombination within the E. moshkovskii population suggested that the apc locus could play a crucial role in determining the virulence of E. moshkovskii.
Molecular prevalence and associated risk factors of Entamoeba spp. in donkeys in Shanxi Province, North China
Background The intestinal protozoa Entamoeba spp. can infect humans and various animals, including donkeys, causing diarrhea and malabsorption and presenting significant risks to animal husbandry and public health. Most Entamoeba species are not pathogenic except for Entamoeba histolytica . China has among the highest rates of donkey farming worldwide. Donkey ( Equus asinus ) farming is increasingly important in China because of their draft and medicinal value; however, epidemiological data on Entamoeba spp. in donkeys remains limited globally. This study aimed to investigate the prevalence of Entamoeba in donkeys in Shanxi Province, North China, and assess associated risk factors using a molecular approach. Methods Fecal samples of 815 donkeys from three representative geographical locations in Shanxi Province were collected to investigate the presence of Entamoeba spp. A portion of the small-subunit rRNA gene (SSU rRNA) was amplified and sequenced to determine the prevalence and species/genotypes of Entamoeba spp. Statistical analysis of possible risk factors was performed using Statistical Product and Service Solutions (SPSS) 26.0 software. The phylogenetic relationship of Entamoeba spp. was reconstructed using the neighbor-joining (NJ) method in Molecular Evolutionary Genetics Analysis (Mega) 7.0 software. Results The overall prevalence of Entamoeba spp. in donkeys in Shanxi Province was 7.12% (58/815). Two species ( Entamoeba sp. RL9 and Entamoeba equi ) were identified by sequence analysis; of these, Entamoeba sp. RL9 was the most prevalent species in donkeys in this study. Statistical analysis revealed that the donkeys' sex, region, age, and altitude are the risk factors associated with Entamoeba spp. prevalence ( P  < 0.05). Phylogenetic analysis indicated that the sequences of Entamoeba sp. RL9 and E. equi isolated from donkeys in this study were clustered with previously reported animal-derived Entamoeba sp. RL9 and E. equi sequences, respectively. Conclusions This study reports the occurrence and prevalence of Entamoeba spp. in donkeys worldwide for the first time to our knowledge. This not only expands the geographical distribution but also broadens the host range of Entamoeba spp., addressing the knowledge gap regarding the prevalence of Entamoeba spp. in donkeys, providing baseline data for carrying out prevention and control of Entamoeba spp. in donkeys in China. Graphical Abstract