Alejandro Dashti

Centro Nacional de Microbiologia

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David Carmena

Centro Nacional de Microbiologia

Pamela C. Köster

Universidad Alfonso X el Sabio

Begoña Bailo

Centro Nacional de Microbiologia

David González‐Barrio

Instituto de Salud Carlos III

Rafael Calero‐Bernal

Universidad Complutense de Madrid

Mónica Santı́n

United States Department of Agriculture

Aly Salimo Muadica

Instituto de Salud Carlos III

Carolina Hernández‐Castro

Universidad de Antioquia

Jenny G. Maloney

United States Department of Agriculture

Ana M. Figueiredo

University of Aveiro

Cooperative Institutions

Instituto de Salud Carlos III

Centro Nacional de Microbiologia

Universidad Complutense de Madrid

University of Aveiro

Centro de Investigación Biomédica en Red

Instituto de Investigación en Recursos Cinegéticos

Chinese Academy of Sciences

Universitat Autònoma de Barcelona

Consejo Superior de Investigaciones Científicas

University of Córdoba

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Correction: Blastocystis occurrence and subtype diversity in European wild boar (Sus scrofa) from the Iberian Peninsula

Veterinary Research (2024)

Pamela C. Köster Ana M. Figueiredo Jenny G. Maloney Alejandro Dashti Begoña Bailo

Wild boar

Blastocystis

Peninsula

10.1186/s13567-024-01408-5

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Microscopy detection and molecular characterisation of Giardia duodenalis infection in outpatients seeking medical care in Egypt

Frontiers in Public Health (2024)

Ehab Kotb Elmahallawy Ahmed Gareh Marwa M. I. Ghallab Pamela C. Köster Alejandro Dashti

Introduction Giardiosis remains one of the most prevalent enteric parasitic infections globally. Earlier molecular-based studies conducted in Egypt have primarily focused on paediatric clinical populations and most were based on single genotyping markers. As a result, there is limited information on the frequency and genetic diversity of G. duodenalis infections in individuals of all age groups. Methods Individual stool samples ( n = 460) from outpatients seeking medical care were collected during January–December 2021 in Kafr El-Sheikh governorate, northern Egypt. Initial screening for the presence of G. duodenalis was conducted by coprological examination. Microscopy-positive samples were further confirmed by real-time PCR. A multilocus sequence typing approach targeted amplification of the glutamate dehydrogenase ( gdh ), beta- giardin ( bg ), and triose phosphate isomerase ( tpi ) genes was used for genotyping purposes. A standardised epidemiological questionnaire was used to gather basic sociodemographic and clinical features of the recruited patients. Results Giardia duodenalis cysts were observed in 5.4% (25/460, 95% CI: 3.6–7.9) of the stool samples examined by conventional microscopy. The infection was more frequent in children under the age of 10 years and in individuals presenting with diarrhoea but without reaching statistical significance. Stool samples collected during the winter period were more likely to harbour G. duodenalis . All 25 microscopy-positive samples were confirmed by real-time PCR, but genotyping data was only available for 56.0% (14/25) of the isolates. Sequence analyses revealed the presence of assemblages A (78.6%, 11/14) and B (21.4%, 3/14). All assemblage A isolates were identified as sub-assemblage AII, whereas the three assemblage B sequences belonged to the sub-assemblage BIII. Patients with giardiosis presenting with diarrhoea were more frequently infected by the assemblage A of the parasite. Conclusion This is one of the largest epidemiological studies evaluating G. duodenalis infection in individuals of all age groups in Egypt. Our molecular data suggest that G. duodenalis infections in the surveyed population are primarily of anthropic origin. However, because assemblages A and B are zoonotic, some of the infections identified can have an animal origin. Additional investigations targeting animal (domestic and free-living) and environmental (water) samples are warranted to better understand the epidemiology of giardiosis in Egypt.

Giardia

Multilocus sequence typing

Giardia lamblia

Parasitology

Molecular Epidemiology

10.3389/fpubh.2024.1377123

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Evaluation of a Novel Commercial Real-Time PCR Assay for the Simultaneous Detection of Cryptosporidium spp., Giardia duodenalis, and Entamoeba histolytica

Microbiology Spectrum (2022)

Alejandro Dashti Henar Alonso Cristina Escolar-Miñana Pamela C. Köster Begoña Bailo

Cryptosporidium spp., Giardia duodenalis, and Entamoeba histolytica are the most common diarrhea-causing protozoan species globally. Misdiagnosis is a concern for asymptomatic and chronic infections. Multiplexing, i.e., the detection of more than one parasite in a single test by real-time PCR, allows high diagnostic performance with favorable cost-effectiveness. We conducted a clinical evaluation of the VIASURE Cryptosporidium, Giardia, & E. histolytica real-time PCR assay (CerTest Biotec, San Mateo de Gállego, Spain) against a large panel (n = 358) of well-characterized DNA samples positive for Cryptosporidium spp. (n = 96), G. duodenalis (n = 115), E. histolytica (n = 25), and other parasitic species of the phyla Amoebozoa (n = 11), Apicomplexa (n = 14), Euglenozoa (n = 8), Heterokonta (n = 42), Metamonada (n = 37), Microsporidia (n = 4), and Nematoda (n = 6). DNA samples were obtained from clinical stool specimens or cultured isolates in a national reference center. Estimated sensitivity and specificity were 0.96 and 0.99 for Cryptosporidium spp., 0.94 and 1 for G. duodenalis, and 0.96 and 1 for E. histolytica, respectively. Positive and negative predictive values were calculated as 1 and 0.98 for Cryptosporidium spp., 0.99 and 0.98 for G. duodenalis, and 1 and 0.99 for E. histolytica, respectively. The assay identified six Cryptosporidium species (Cryptosporidium hominis, Cryptosporidium parvum, Cryptosporidium canis, Cryptosporidium felis, Cryptosporidium scrofarum, and Cryptosporidium ryanae) and four G. duodenalis assemblages (A, B, C, and F). The VIASURE assay provides rapid and accurate simultaneous detection and identification of the most commonly occurring species and genetic variants of diarrhea-causing parasitic protozoa in humans. IMPORTANCE Thorough independent assessment of the diagnostic performance of novel diagnostic assays is essential to ascertain their true usefulness and applicability in routine clinical practice. This is particularly true for commercially available kits based on multiplex real-time PCR aimed to detect and differentiate multiple pathogens in a single biological sample. In this study, we conducted a clinical evaluation of the VIASURE Cryptosporidium, Giardia, & E. histolytica real-time PCR assay (CerTest Biotec) for the detection and identification of the diarrhea-causing enteric protozoan parasites Cryptosporidium spp., G. duodenalis, and E. histolytica. A large panel of well-characterized DNA samples from clinical stool specimens or cultured isolates from a reference center was used for this purpose. The VIASURE assay demonstrated good performance for the routine testing of these pathogens in clinical microbiological laboratories.

Giardia

Multiplex

10.1128/spectrum.00531-22

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Molecular characteristics and zoonotic potential of enteric protists in domestic dogs and cats in Egypt

Frontiers in Veterinary Science (2023)

Ehab Kotb Elmahallawy Ahmed Gareh Akram Abu-Okail Pamela C. Köster Alejandro Dashti

Domestic dogs and cats can be a source of human infection by a wide diversity of zoonotic pathogens including parasites. Genotyping and subtyping tools are useful in assessing the true public health relevance of canine and feline infections by these pathogens. This study investigated the occurrence, genetic diversity, and zoonotic potential of common diarrhea-causing enteric protist parasites in household dogs and cats in Egypt, a country where this information is particularly scarce.In this prospective, cross-sectional study a total of 352 individual fecal samples were collected from dogs (n = 218) and cats (n = 134) in three Egyptian governorates (Dakahlia, Gharbeya, and Giza) during July-December 2021. Detection and identification of Cryptosporidium spp., Giardia duodenalis, Enterocytozoon bieneusi, and Blastocystis sp. were carried out by PCR and Sanger sequencing. Basic epidemiological variables (geographical origin, sex, age, and breed) were examined for association with occurrence of infection by enteric protists.The overall prevalence rates of Cryptosporidium spp. and G. duodenalis were 1.8% (95% CI: 0.5-4.6) and 38.5% (95% CI: 32.0-45.3), respectively, in dogs, and 6.0% (95% CI: 2.6-11.4) and 32.1% (95% CI: 24.3-40.7), respectively, in cats. All canine and feline fecal samples analyzed tested negative for E. bieneusi and Blastocystis sp. Dogs from Giza governorate and cats from Dakahlia governorate were at higher risk of infection by Cryptosporidium spp. (p = 0.0006) and G. duodenalis (p = 0.00001), respectively. Sequence analyses identified host-adapted Cryptosporidium canis (n = 4, one of them belonging to novel subtype XXe2) and G. duodenalis assemblages C (n = 1) and D (n = 3) in dogs. In cats the zoonotic C. parvum (n = 5) was more prevalent than host-adapted C. felis (n = 1). Household dogs had a limited (but not negligible) role as source of human giardiasis and cryptosporidiosis, but the unexpected high frequency of zoonotic C. parvum in domestic cats might be a public health concern. This is the first molecular-based description of Cryptosporidium spp. infections in cats in the African continent to date. Molecular epidemiological data provided here can assist health authorities and policy makers in designing and implementing effective campaigns to minimize the transmission of enteric protists in Egypt.

Blastocystis

Giardia

Zoonosis

10.3389/fvets.2023.1229151

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Molecular Detection and Characterization of Intestinal and Blood Parasites in Wild Chimpanzees (Pan troglodytes verus) in Senegal

Animals (2021)

Pamela C. Köster Justinn Renelies‐Hamilton Laia Dotras Manuel Llana Celia Vinagre‐Izquierdo

Wild chimpanzee populations in West Africa (Pan troglodytes verus) have dramatically decreased as a direct consequence of anthropogenic activities and infectious diseases. Little information is currently available on the epidemiology, pathogenic significance, and zoonotic potential of protist species in wild chimpanzees. This study investigates the occurrence and genetic diversity of intestinal and blood protists as well as filariae in faecal samples (n = 234) from wild chimpanzees in the Dindefelo Community Nature Reserve, Senegal. PCR-based results revealed the presence of intestinal potential pathogens (Sarcocystis spp.: 11.5%; Giardia duodenalis: 2.1%; Cryptosporidium hominis: 0.9%), protist of uncertain pathogenicity (Blastocystis sp.: 5.6%), and commensal species (Entamoeba dispar: 18.4%; Troglodytella abrassarti: 5.6%). Entamoeba histolytica, Enterocytozoon bieneusi, and Balantioides coli were undetected. Blood protists including Plasmodium malariae (0.4%), Trypanosoma brucei (1.3%), and Mansonella perstans (9.8%) were also identified. Sanger sequencing analyses revealed host-adapted genetic variants within Blastocystis, but other parasitic pathogens (C. hominis, P. malariae, T. brucei, M. perstans) have zoonotic potential, suggesting that cross-species transmission between wild chimpanzees and humans is possible in areas where both species overlap. Additionally, we explored potential interactions between intestinal/blood protist species and seasonality and climate variables. Chimpanzees seem to play a more complex role on the epidemiology of pathogenic and commensal protist and nematode species than initially anticipated.

Blastocystis

Protist

Giardia

Entamoeba

10.3390/ani11113291

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Citations (8)

Unveiling Blastocystis epidemiology in Morocco: subtype diversity among clinical patients with and without gastrointestinal manifestations in the Meknes region

Parasitology Research (2024)

Mounia Boutahar Mourad Belaouni Azeddine Ibrahimi Rachid Eljaoudi Tarik Aanniz

Blastocystis

Medical microbiology

10.1007/s00436-024-08288-w

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Occurrence and genetic diversity of Enterocytozoon bieneusi (Microsporidia) in owned and sheltered dogs and cats in Northern Spain

Parasitology Research (2019)

Alejandro Dashti Mónica Santı́n Lourdes Cano Aida de Lucio Begoña Bailo

Enterocytozoon bieneusi

Zoonosis

10.1007/s00436-019-06428-1

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Citations (46)

Blastocystis occurrence and subtype diversity in European wild boar (Sus scrofa) from the Iberian Peninsula

Veterinary Research (2024)

Pamela C. Köster Ana M. Figueiredo Jenny G. Maloney Alejandro Dashti Begoña Bailo

The ongoing increase in wild boar populations across Europe has fostered human-wildlife conflicts, including the transmission of emerging pathogens with zoonotic importance. Blastocystis is a ubiquitous, faecal-oral transmitted protist that can cause gastrointestinal illnesses and is observed in humans and animals worldwide. The role of wildlife in the epidemiology of Blastocystis is insufficiently understood. Thus, we investigated the occurrence and subtype diversity of Blastocystis in free-ranging wild boars from the Iberian Peninsula using conventional PCR and next-generation amplicon sequencing of a fragment of the ssu RNA gene. A total of 459 wild boar faecal samples were collected across Spain (n = 360) and Portugal (n = 99) between 2014 and 2021. Blastocystis was present in 15.3% (70/459; 95% CI 12.1-18.9) of the wild boars analysed, and its occurrence was significantly higher in Portugal (34.3%, 34/99; 95% CI 25.1-44.6) than in Spain (10.0%, 36/360; 95% CI 7.1-13.6). Seven Blastocystis subtypes (ST5, ST10b, ST13-ST15, ST24b, and ST43) were detected among the surveyed wild boar populations, with greater variability detected in Portuguese samples. ST5 was identified in all the Blastocystis-positive animals, whereas 14.3% of them harboured ST mixed colonisations. Our results demonstrate that Blastocystis ST5 is particularly adapted to infect wild boars. The additional identification of zoonotic STs reinforces the role of wild boars as spreaders of zoonotic infections with public health significance.

Wild boar

Peninsula

Blastocystis

10.1186/s13567-024-01385-9

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Citations (3)

Enterocytozoon bieneusi (Microsporidia): Identification of novel genotypes and evidence of transmission between sympatric wild boars ( Sus scrofa ferus ) and Iberian pigs ( Sus scrofa domesticus ) in Southern Spain

Transboundary and Emerging Diseases (2020)

Alejandro Dashti António Rivero‐Juarez Mónica Santı́n Pedro López‐López Javier Caballero‐Gómez

Microsporidia is a phylum of obligate emergent intracellular protist-like fungi pathogens that infect a broad range of hosts including vertebrates and invertebrates. Enterocytozoon bieneusi is the most common cause of microsporidiosis in humans, affecting primarily immunosuppressed patients but also reported in immunocompetent individuals. Epidemiological information on the presence and molecular diversity of E. bieneusi in livestock and wildlife in Spain is limited. Therefore, the occurrence of this microsporidia was investigated in sympatric extensively reared Iberian pigs (n = 186) and free ranging wild boars (n = 142) in the province of Córdoba, Southern Spain. Forty-two Iberian pigs (22.6%) and three wild boars (2.1%) were found E. bieneusi positive by PCR. In Iberian pigs, occurrence of E. bieneusi was significantly higher in sows than in fattening pigs (31.6% vs. 11.4%; p = .001). Five genotypes were identified in Iberian pigs, four previously reported (EbpA, PigEb4, O, Pig HN-II) and a novel genotype (named PigSpEb1), while only two genotypes were identified in wild boars, EbpA and novel genotype PigSpEb1. All five genotypes identified belong to Group 1 suggesting zoonotic potential. This study constitutes the first report on the occurrence and molecular characterization of E. bieneusi in Iberian pigs and wild boars. The identification of two genotypes with zoonotic potential in sympatric Iberian pigs and wild boars suggests that E. bieneusi can be potentially transmitted between those two hosts, but also implies that they may act as natural sources of microsporidia infection to other hosts including humans.

Enterocytozoon bieneusi

10.1111/tbed.13658

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Citations (23)

Author response for "Prevalence and public health relevance of enteric parasites in domestic dogs and cats in the region of Madrid (Spain) with an emphasis on <i>Giardia duodenalis</i> and <i>Cryptosporidium</i> sp"

Marta Mateo Ana Montoya Begoña Bailo Pamela C. Köster Alejandro Dashti

Giardia

Enteric virus

Veterinary public health

Giardia lamblia

Enteric fever

Emphasis (telecommunications)

Domestic animal

10.1002/vms3.1270/v3/response1

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