scholarly journals Molecular Detection and Genotyping of Enteric Protists in Asymptomatic Schoolchildren and Their Legal Guardians in Madrid, Spain

Parasitologia ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 83-94
Author(s):  
Pamela Carolina Köster ◽  
Alejandro Dashti ◽  
Lucia Reh ◽  
Begoña Bailo ◽  
Marta Hernández-de-Mingo ◽  
...  

Asymptomatic carriage of diarrhoea-causing enteric protist parasites in the general population is poorly understood, particularly in medium- to high-income countries. This molecular epidemiological survey investigates the presence, molecular diversity, and household transmission of Giardia duodenalis, Cryptosporidium spp., Blastocystis sp., and Enterocystozoon bieneusi in schoolchildren aged 2–13 years (n = 74) and their legal guardians (n = 6) in Madrid, Spain. Enteroparasite detection and genotyping was conducted in stool samples by molecular (PCR and Sanger sequencing) methods. Potential associations linked to infections were investigated through epidemiological questionnaires. Giardia duodenalis was the most prevalent enteric parasite found (14%, 95% CI: 7.1–23), followed by Blastocystis sp. (10%, 95% CI: 6.2–22) and Cryptosporidium spp. (3.8%, 95% CI: 0.78–11). None of the participants tested positive for E. bieneusi. Sequence analyses revealed the presence of G. duodenalis assemblage B, sub-assemblage BIV in a single child. The three Cryptosporidium isolates obtained were assigned to C. hominis, two of them belonging to the gp60 subtype IbA10G2. Four Blastocystis subtypes were identified including ST2 (38%, 3/8), ST3 (25%, 2/8), ST4 (25%, 2/8), and ST8 (12%, 1/8). All G. duodenalis and Cryptosporidium isolates were detected in children only. Blastocystis ST3 and ST4 were circulating in members of the same household. Blastocystis carriage rates increased with the age of the participants. Presence of diarrhoea-causing enteric protists was common in apparently healthy children.

Pathogens ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 684
Author(s):  
Shun-Xian Zhang ◽  
David Carmena ◽  
Cristina Ballesteros ◽  
Chun-Li Yang ◽  
Jia-Xu Chen ◽  
...  

Cryptosporidium spp., Entamoeba histolytica, Giardia duodenalis, and Blastocystis sp. infections have been frequently reported as etiological agents for gastroenteritis, but also as common gut inhabitants in apparently healthy individuals. Between July 2016 and March 2017, stool samples (n = 507) were collected from randomly selected individuals (male/female ratio: 1.1, age range: 38‒63 years) from two sentinel hospitals in Tengchong City Yunnan Province, China. Molecular (PCR and Sanger sequencing) methods were used to detect and genotype the investigated protist species. Carriage/infection rates were: Blastocystis sp. 9.5% (95% CI: 7.1–12.4%), G. duodenalis 2.2% (95% CI: 1.1–3.8%); and E. histolytica 2.0% (95% CI: 0.9–3.6%). Cryptosporidium spp. was not detected at all. Overall, 12.4% (95% CI: 9.7–15.6) of the participants harbored at least one enteric protist species. The most common coinfection was E. histolytica and Blastocystis sp. (1.0%; 95% CI: 0.3–2.2). Sequence analyses revealed that 90.9% (10/11) of the genotyped G. duodenalis isolates corresponded to the sub-assemblage AI. The remaining sequence (9.1%, 1/11) was identified as sub-assemblage BIV. Five different Blastocystis subtypes, including ST3 (43.7%, 21/48), ST1 (27.1%, 13/48), ST7 (18.8%, 9/48), ST4 (8.3%, 4/48), and ST2 (2.1%, 1/48) were identified. Statistical analyses confirmed that (i) the co-occurrence of protist infections was purely random, (ii) no associations were observed among the four protist species found, and (iii) neither their presence, individually or jointly, nor the patient’s age was predictors for developing clinical symptoms associated with these infections. Overall, these protist mono- or coinfections are asymptomatic and do not follow any pattern.


2020 ◽  
Vol 8 (4) ◽  
pp. 466 ◽  
Author(s):  
Aly Salimo Muadica ◽  
Pamela Carolina Köster ◽  
Alejandro Dashti ◽  
Begoña Bailo ◽  
Marta Hernández-de-Mingo ◽  
...  

Enteric parasites including Giardia duodenalis, Cryptosporidium spp., and to a lesser extent, Blastocystis sp. and Enterocytozoon bieneusi, are major worldwide contributors to diarrhoeal disease. Assessing their molecular frequency and diversity is important to ascertain the sources of infection, transmission dynamics, and zoonotic potential. Little molecular information is available on the genotypes of these pathogens circulating in apparently healthy children. Here, we show that asymptomatic carriage of G. duodenalis (17.4%, 95% CI: 15.5–19.4%), Blastocystis sp. (13.0%, 95% CI: 11.4–14.8%), and Cryptosporidium spp. (0.9%, 95% CI: 0.5–1.5%) is common in children (1–16 years; n = 1512) from Madrid, Spain. Our genotyping data indicate that; (i) the observed frequency and diversity of parasite genetic variants are very similar to those previously identified in Spanish clinical samples, so that the genotype alone does not predict the clinical outcome of the infection, (ii) anthroponotic transmission accounts for a large proportion of the detected cases, highlighting that good personal hygiene practices are important to minimizing the risk of infection, (iii) Blastocystis ST4 may represent a subtype of the parasite with higher pathogenic potential, and (iv) Enterocytozoon bieneusi does not represent a public health concern in healthy children.


2020 ◽  
Vol 9 (1) ◽  
pp. 54
Author(s):  
Salem Belkessa ◽  
Daniel Thomas-Lopez ◽  
Karim Houali ◽  
Farida Ghalmi ◽  
Christen Rune Stensvold

The molecular epidemiology of giardiasis in Africa remains unclear. A study was carried out across four hospitals in Algeria. A total of 119 fecal samples from 55 children, 37 adults, and 27 individuals of undetermined age, all scored positive for intestinal parasites by microscopy, and were screened by real-time PCR for Giardia. Molecular characterization of Giardia was performed by assemblage-specific PCR and PCR targeting the triose phosphate isomerase gene (tpi). Of the 119 samples, 80 (67%) were Giardia-positive by real-time PCR. For 48 moderately-highly real-time PCR-positive samples, tpi genotyping assigned 22 samples to Assemblage A and 26 to Assemblage B. Contrary to Assemblage A, Assemblage B exhibited substantial genetic diversity and allelic heterozygosity. Assemblage-specific PCR proved to be specific for discriminating Assemblage A or B but not as sensitive as tpi genotyping. We confirmed that real-time PCR is more sensitive than microscopy for detecting Giardia in stool samples and that robust amplification and sequencing of the tpi gene is feasible when moderate-to-strongly real-time PCR-positive samples are used. This study is one of the few performed in Africa providing genotyping data on Giardia infections in humans. Both assemblages A and B were commonly seen and not associated with specific sociodemographic data.


2017 ◽  
Vol 117 (2) ◽  
pp. 447-451 ◽  
Author(s):  
Marijo Parčina ◽  
Ingrid Reiter-Owona ◽  
Frank P. Mockenhaupt ◽  
Valerija Vojvoda ◽  
Jean Bosco Gahutu ◽  
...  

2019 ◽  
Vol 13 (10) ◽  
pp. 927-932
Author(s):  
Sedat Vezir ◽  
Filiz Kaya ◽  
Emine Vezir ◽  
Nermin Karaosmanoğlu ◽  
Ali Kudret Adiloğlu

Introduction: Chronic spontaneous urticaria (CSU) which develops without a known stimulation is defined as the occurrence of spontaneous wheals, angioedema or both for longer than six weeks. Infections, autoimmunity, food intolerance and internal parasitic infections are supposed to be underlying causes of CSU. The aim of this study was to evaluate the intestinal parasites in children and adult patients diagnosed as CSU, to determine the frequency of parasites in chronic urticaria, and to compare these patients with healthy demographic control groups. Methodology: Seventy six children and 38 adult patients with CSU were examined in terms of parasitic infections. The patients whom parasites were detected received anti-parasitic therapy and the improvements in CSU symptoms were evaluated. Stool samples were examined with direct microscopic examination (native-lugol), stool concentration and trichrome staining methods. Results: In pediatric patient group, 18.4% (n = 14) of the stool samples were positive for Blastocystis sp., 2.6% (n = 2), Dientamoeba fragilis and 1.3% (n = 1), Giardia duodenalis. In adult patient group, Blastocystis sp. was detected in 18.4% (n = 7) of the stool samples. Anti-parasitic therapy yielded substantial improvement in urticaria symptoms in 57.1% of pediatric and 60.0% of adult patients. Conclusions: Blastocystis sp. and D. fragilis may play a role in chronic urticaria which seriously disrupts the patient's quality of life. Parasitic infections should not be neglected in patients with cutaneous manifestations.


Pathogens ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 894
Author(s):  
Dongmi Kwak ◽  
Min-Goo Seo

Feral cats that are roaming outside can serve as reservoirs for zoonotic pathogens, negatively impacting public health. They may experience high levels of parasitic infection. Some gastrointestinal protozoa and microsporidia possessing zoonotic potential in cats include Cryptosporidium spp., Giardia duodenalis, Blastocystis sp., Enterocytozoon bieneusi, and Toxoplasma gondii. Here, we show the infection rates and risk factors of intestinal protozoa and microsporidia detected from shelter cats on Jeju Island in South Korea in 2020. Among 158 cats, we detected genes for five internal protozoa and microsporidia, namely, Cryptosporidium felis (0.6%), G. duodenalis (3.8%), Blastocystis sp. (0.6%), E. bieneusi (3.8%), and T. gondii (1.3%). Furthermore, 16 cats (10.1%) were PCR-positive for at least one protozoan or microsporidium. To our knowledge, this study is the first to describe the existence of C. felis, G. duodenalis assemblage F, Blastocystis sp. ST4 subtype, and E. bieneusi genotype Peru11 in cats in South Korea. Despite the small number of positive samples, this study expands our understanding of the incidence of zoonotic gastrointestinal protozoa and microsporidia in shelter cats and genetically characterizes the isolates found in the infected animals. Moreover, these findings emphasize the need for a better control strategy on protozoa and microsporidia in cats, tailored to their individual needs, to protect animal and public health.


Parasitology ◽  
2013 ◽  
Vol 141 (2) ◽  
pp. 206-215 ◽  
Author(s):  
ÁNGELA FERNÁNDEZ-ÁLVAREZ ◽  
AARÓN MARTÍN-ALONSO ◽  
NÉSTOR ABREU-ACOSTA ◽  
CARLOS FELIU ◽  
JEAN-PIERRE HUGOT ◽  
...  

SUMMARYThe flagellated parasite Giardia duodenalis is known as one of the most common causes of protozoal diarrhoea in both humans and animals worldwide. The aim of the present work was to perform the first study of G. duodenalis in rodents in the Canary Islands (Spain) and analyse the level of genetic variation and the potential zoonotic role of the isolates. Stool samples were collected from 284 wild rodents and Giardia cysts were detected by light microscopy. The overall prevalence of giardiasis was 25·4% and ranged from 19·4% in El Hierro to 34% in Gran Canaria. Positive samples were further characterized by PCR and nucleotide sequencing of the triose phosphate isomerase (TPI), β-giardin (BG) and glutamate dehydrogenase (GDH) genes. Our study revealed assemblage G as the most frequent genotype and identified two rodent-infecting G. duodenalis haplotypes of this assemblage, HI and HII. Phylogenetic analysis supported the monophyly of haplotype HI, which we suggest to be considered as a novel G. duodenalis sub-assemblage GII, due to the high genetic distances among this sub-genotype and assemblage G. Furthermore, G. duodenalis assemblage B was detected in an inhabited area in La Palma, a fact that may pose a potential risk of G. duodenalis transmission from rodents to humans.


Pathogens ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 255 ◽  
Author(s):  
Aly S. Muadica ◽  
Pamela C. Köster ◽  
Alejandro Dashti ◽  
Begoña Bailo ◽  
Marta Hernández-de-Mingo ◽  
...  

Infections by the protist enteroparasites Giardia duodenalis, Cryptosporidium spp., and, to a much lesser extent, Blastocystis sp. are common causes of childhood diarrhoea in low-income countries. This molecular epidemiological study assesses the frequency and molecular diversity of these pathogens in faecal samples from asymptomatic schoolchildren (n = 807) and symptomatic children seeking medical attention (n = 286) in Zambézia province, Mozambique. Detection and molecular characterisation of pathogens was conducted by polymerase chain reaction (PCR)-based methods coupled with Sanger sequencing. Giardia duodenalis was the most prevalent enteric parasite found [41.7%, 95% confidence interval (CI): 38.8–44.7%], followed by Blastocystis sp. (14.1%, 95% CI: 12.1–16.3%), and Cryptosporidium spp. (1.6%, 95% CI: 0.9–2.5%). Sequence analyses revealed the presence of assemblages A (7.0%, 3/43) and B (88.4%, 38/43) within G. duodenalis-positive children. Four Cryptosporidium species were detected, including C. hominis (30.8%; 4/13), C. parvum (30.8%, 4/13), C. felis (30.8%, 4/13), and C. viatorum (7.6%, 1/13). Four Blastocystis subtypes were also identified including ST1 (22.7%; 35/154), ST2 (22.7%; 35/154), ST3 (45.5%; 70/154), and ST4 (9.1%; 14/154). Most of the genotyped samples were from asymptomatic children. This is the first report of C. viatorum and Blastocystis ST4 in Mozambique. Molecular data indicate that anthropic and zoonotic transmission (the latter at an unknown rate) are important spread pathways of diarrhoea-causing pathogens in Mozambique.


2020 ◽  
Vol 8 (9) ◽  
pp. 1408
Author(s):  
Salma Khaled ◽  
Nausicaa Gantois ◽  
Amadou Tidjani Ly ◽  
Simon Senghor ◽  
Gaël Even ◽  
...  

Blastocystis sp. is an enteric protozoan that frequently colonizes humans and many animals. Despite impacting on human health, data on the prevalence and subtype (ST) distribution of Blastocystis sp. remain sparse in Africa. Accordingly, we performed the first multicenter and largest epidemiological survey ever conducted on Blastocystis sp. for this continent. A total of 731 stool samples collected from healthy school children living in 10 villages of the northwestern region of Senegal were tested for the presence of Blastocystis sp. by real-time polymerase chain reaction followed by subtyping of positive samples. Considerable variation in prevalence between villages (51.7 to 100%) was evident with the overall prevalence being 80.4%. Mixed infections were identified in 23% of positive individuals. Among 453 school children with a single infection, ST2 was predominant, followed by ST1, ST3, ST7, ST10, and ST14; this is the first report of ST10 and ST14 in humans. Genetic polymorphisms were evident at the intra-ST level with the identification of numerous ST1 to ST3 genotypes. ST1 showed the greatest intra-ST diversity followed by ST2 and ST3. The prevalence and distribution of STs and genotypes varied among target villages, pointing to several potential infection sources, including human-to-human, zoonotic, and waterborne transmission.


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