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1.
Parasitology ; 148(8): 975-984, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33775260

RESUMO

Cryptosporidiosis is a gastrointestinal illness with profuse diarrhoea. Although there are no other Food and Drug Administration (FDA)-approved alternatives for the treatment of cryptosporidiosis, nitazoxanide (NTZ) can be qualified as partially effective. In immunosuppressed conditions, severe and/or disseminated cryptosporidiosis may occur and patients should be treated parenterally. To achieve the goal of developing parenteral treatment for cryptosporidiosis, the current study was undertaken to investigate the in vitro and in vivo anticryptosporidial activity of aminoxanide. This new l-tert-leucyl thiazolide is a soluble prodrug of tizoxanide (TIZ), the main metabolite of NTZ. Confirming the good efficacy of aminoxanide in Cryptosporidium parvum-infected HCT-8 cells with a 50% inhibitory concentration of 1.55 µm (±0.21), in immunosuppressed C. parvum-infected Mongolian gerbils (Meriones unguiculatus), a 5-day treatment with a daily intramuscular dose of 100 mg kg−1 aminoxanide resulted in a 72.5% oocyst excretion inhibition, statistically equivalent to 75.5% in gerbils treated with a 4-fold lower oral dose of NTZ. Cryptosporidium parvum-induced intestinal pathology and inflammation were improved. Aminoxanide provides an injectable form of TIZ that NTZ was unable to do and is a promising drug for which optimization of the formulation should be further explored. These results represent a first promising step towards the goal of developing a parenteral treatment for cryptosporidiosis.


Assuntos
Criptosporidiose/tratamento farmacológico , Cryptosporidium parvum/efeitos dos fármacos , Ésteres/uso terapêutico , Pró-Fármacos/uso terapêutico , Tiazóis/uso terapêutico , Animais , Bovinos , Linhagem Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ésteres/química , Ésteres/farmacologia , Fezes/parasitologia , Feminino , Gerbillinae , Íleo/parasitologia , Íleo/patologia , Concentração Inibidora 50 , Masculino , Estrutura Molecular , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Tiazóis/química , Tiazóis/farmacologia
2.
J Antimicrob Chemother ; 73(7): 1895-1898, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29596605

RESUMO

Background: Acanthamoeba keratitis (AK) is a sight-threatening infectious disease. Its effective and safe medical therapy remains highly debated. Recently, voriconazole, a monotriazole with noted in vitro activity against a large variety of fungi, has been successfully used both topically and systemically to treat human AK cases. Objectives: To measure anti-Acanthamoeba polyphaga in vitro activity, anti-rat AK efficiency and rat cornea penetration of eye-drop and oral voriconazole. Methods: A. polyphaga was maintained in axenic cultures. In vitro, amoebicidal and cysticidal activities of voriconazole were measured using an XTT assay. AK lesions of Sprague Dawley rats were scored from grade 0 to grade 3. For 21 days, from day 7 post-infection, voriconazole (1% solution) eye drops were instilled or voriconazole was administered by gavage (60 mg/kg/day). After killing, superficial corneal epithelium scrapings were cultured and analysed by PCR, and eye-globe histology was performed. Cornea and plasma concentrations were determined using 2D HPLC separation and tandem MS. Results: In vitro, voriconazole inhibited trophozoite proliferation with an IC50 value of 0.02 mg/L and an IC90 value of 2.86 mg/L; no cysticidal effect was found. In AK rats, eye drops reduced clinical worsening from day 7 to day 14 post-infection and oral voriconazole was not effective. Voriconazole cornea concentrations were directly dependent on the frequency of eye-drop instillations, which resulted in lower plasma concentrations, whilst oral voriconazole resulted in lower cornea concentrations. Conclusions: Present data underline the need for high-frequency eye-drop instillation regimens for efficient AK therapy.


Assuntos
Ceratite por Acanthamoeba/tratamento farmacológico , Acanthamoeba/efeitos dos fármacos , Antiprotozoários/farmacologia , Córnea/efeitos dos fármacos , Voriconazol/farmacologia , Acanthamoeba/genética , Administração Oral , Animais , Antiprotozoários/administração & dosagem , Cultura Axênica , Córnea/parasitologia , Masculino , Testes de Sensibilidade Microbiana , Soluções Oftálmicas/administração & dosagem , Soluções Oftálmicas/farmacologia , Ratos , Ratos Sprague-Dawley , Voriconazol/administração & dosagem
3.
Exp Parasitol ; 192: 108-112, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30107154

RESUMO

Cryptosporidiosis is a common disease in children and immunodeficient individuals. In 2006, a national network was set up on the surveillance of human cryptosporidiosis in France. Since January 2015, the 41 tertiary care hospitals and the 3 private laboratories of the French National Network on the surveillance of human cryptosporidiosis have been able to declare confirmed cases of cryptosporidiosis online. Between 2015 and 2017, 210 cases of cryptosporidiosis were declared in immunodeficient patients in France; Cryptosporidium parvum and Cryptosporidium hominis represented 66% and 22% of cases, respectively. A peak was observed in autumn. Cryptosporidiosis occurred mainly in a context of solid organ transplantation (SOT) (49%) and of HIV infection (30%). In SOT recipients, cryptosporidiosis appeared more frequently in the first 6 months post transplantation. Regarding cases declared in SOT recipients, mycophenolate mofetil was used in 68%. A mortality rate of 6% was observed. Present results underline the importance of screening for cryptosporidiosis in immunocompromised patients suffering from diarrhea, especially in the course of major cell mediated immunodeficiency or even systematic screening before SOT. Exclusive Cryptosporidium free water feeding could be suggested during major cell mediated immunodeficiency.


Assuntos
Criptosporidiose/epidemiologia , Hospedeiro Imunocomprometido , Imunoterapia/efeitos adversos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Criptosporidiose/imunologia , Ciclosporina/efeitos adversos , Ciclosporina/uso terapêutico , Feminino , França/epidemiologia , Humanos , Terapia de Imunossupressão/efeitos adversos , Terapia de Imunossupressão/métodos , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Imunoterapia/métodos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/efeitos adversos , Ácido Micofenólico/uso terapêutico , Fatores de Risco , Tacrolimo/efeitos adversos , Tacrolimo/uso terapêutico , Adulto Jovem
4.
Malar J ; 13: 110, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24649924

RESUMO

BACKGROUND: A flow cytometric method is proposed to study in vitro drug sensitivity of Plasmodium falciparum. Standard [(3)H]-hypoxanthine incorporation assay gives only information on inhibition of maturation by drugs. This method is usable on field isolates and provides data on both inhibition of maturation and re-invasion. METHODS: The method is based on the staining of parasites with hydroethidine (HE) and thiazole orange (TO) which allow differential identification of early, trophozoite and late stage of the parasite by flow cytometry. Late stages of the parasites are obtained by incubation in culture for 24 hours. Reinvasion is followed by culturing parasitized red blood cells for 24 h more. RESULTS: Compared to the standard [(3)H]-hypoxanthine incorporation assay, it gave similar results as expressed by 50% inhibitory concentrations for chloroquine of laboratory strains and "field" isolates. The effect of quinine on the schizont-ring transition was also explored using this method. First data on the inhibition of re-invasion induced by quinine are presented for both P. falciparum-cultured strains and field isolates. DISCUSSION: This method is simple to use event for field isolate study. It is suitable to analyse effect of drugs on steps of the parasite life cycle different for the maturation one. Using this method quinine was found to have a inhibitory effect on re-invasion of red cells by Plasmodium.


Assuntos
Antimaláricos/farmacologia , Benzotiazóis , Resistência a Medicamentos , Citometria de Fluxo/métodos , Corantes Fluorescentes , Fenantridinas , Plasmodium falciparum/efeitos dos fármacos , Quinolinas , Cloroquina/farmacologia , Concentração Inibidora 50 , Quinina/farmacologia
5.
Int J Food Microbiol ; 388: 110085, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36652747

RESUMO

Cryptosporidium is the causative agent of cryptosporidiosis, which results, among others, in profuse diarrhoea. Transmission to humans occurs via the faecal-oral route directly by contact with infected hosts or indirectly by waterborne or foodborne routes. For the latter, parasite transmission is closely linked to the oocyst's ability to persist and survive in food matrices. In this study, we evaluated the persistence and survival of Cryptosporidium oocysts in lamb's lettuce: i) during plant growth and ii) in conditions mimicking the industrial washing process applied in minimally-processed vegetables (MPV). Results show that oocysts persisted during the growth of lamb's lettuce, i.e. two months from the 2-leaf stage until the 8-leaf harvest time (-0.89 Log10 of oocysts). However, their survival decreased from as early as one week (-0.61 Log10), and only 6 % of oocysts remained infective at the time of harvest. The washing process had a limited effect on parasite load (<0.5 Log10) and no effect on survival; chlorination of washing water did not improve the efficiency (removal and inactivation) of the process. The ability of C. parvum to persist and survive throughout the food chain may drive its transmission to humans through MPV products. Appropriate management measures should be implemented at each operational level to limit contamination and ensure food safety of fresh produce.


Assuntos
Criptosporidiose , Cryptosporidium parvum , Cryptosporidium , Saladas , Valerianella , Humanos , Animais , Criptosporidiose/prevenção & controle , Oocistos , Folhas de Planta
6.
Viruses ; 15(2)2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36851577

RESUMO

The estimated prevalence rate of adults living with HIV infection in MENA is one of the lowest in the world. To date, no data on the genetic characteristics of Cryptosporidium isolates from HIV/AIDS patients in Algeria were available. This study aimed to identify Cryptosporidium species and subtype families prevalent in Algerian HIV-infected patients and contribute to the molecular epidemiology mapping of Cryptosporidium in the MENA region. A total of 350 faecal specimens from HIV/AIDS patients were analysed using microscopy, and a Cryptosporidium infection was identified from 33 samples, with 22 isolates successfully sequencing and confirming species and subtypes. Based on sequence analysis, 15 isolates were identified as C. parvum with family subtypes IIa (n = 7) and IId (n = 8), while five were identified as C. hominis (family subtypes Ia (n = 2) and Ib (n = 3)) and two as C. felis. The C. parvum subtype families IIa and IId predominated, suggesting potential zoonotic transmission. More extensive sampling of both humans and farm animals, especially sheep, goats and calves, as well as a collection of epidemiological data are needed for a better understanding of the sources of human C. parvum infections in Algeria.


Assuntos
Síndrome da Imunodeficiência Adquirida , Criptosporidiose , Cryptosporidium , Infecções por HIV , Adulto , Humanos , Animais , Ovinos , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Criptosporidiose/epidemiologia , Argélia/epidemiologia , Cryptosporidium/genética , Cabras
7.
Parasite ; 30: 31, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37606589

RESUMO

Free-Living Amebae (FLA) and Cryptosporidium oocysts occasionally share the same environment. From 2004 to 2016, Cryptosporidium was responsible for 60% of 905 worldwide waterborne outbreaks caused by protozoan parasites. The aim of this study was to evaluate interactions between C. parvum oocysts and two common FLAs (Acanthamoeba castellanii and Vermamoeba vermiformis) in a water environment. Encystment and survival of FLAs were evaluated by microscopy using trypan blue vital coloration. Oocysts were numerated on microscopy. Interactions were studied over time in conditions both unfavorable and favorable to phagocytosis. Potential phagocytosis was directly evaluated by several microscopic approaches and indirectly by numeration of microorganisms and oocyst infectivity evaluation. Occasional phagocytosis of C. parvum by FLAs was documented. However, oocyst concentrations did not decrease significantly, suggesting resistance of oocysts to phagocytosis. A temporary decrease of oocyst infectivity was observed in the presence of A. castellanii. The effect of these interactions on C. parvum infectivity is particularly interesting. The biofilm condition could favor the persistence or even the proliferation of oocysts over time. This study demonstrated interactions between C. parvum and FLAs. Further knowledge of the mechanisms involved in the decrease of oocyst infectivity in the presence of A. castellanii could facilitate the development of new therapeutic approaches.


Title: Interactions entre amibes libres et Cryptosporidium parvum : étude expérimentale. Abstract: Les amibes libres et les oocystes de Cryptosporidium partagent parfois le même environnement. Entre 2004 et 2016, Cryptosporidium a été responsable de 60 % des 905 épidémies d'origine hydrique dans le monde causées par des parasites protozoaires. Le but de cette étude était d'évaluer les interactions entre les oocystes de C. parvum et deux espèces d'amibes libres communes (Acanthamoeba castellanii et Vermamoeba vermiformis) en environnement aquatique. L'enkystement et la survie des amibes libres ont été évalués par microscopie en utilisant une coloration vitale au bleu trypan. Les oocystes ont été comptés au microscope. Les interactions ont été étudiées au cours du temps dans des conditions à la fois défavorables et favorables à la phagocytose. La phagocytose potentielle a été évaluée directement par plusieurs approches microscopiques et indirectement par la numération des micro-organismes et l'évaluation de l'infectiosité des oocystes. Une phagocytose occasionnelle de C. parvum par amibes libre a été documentée. Cependant, les concentrations d'oocystes n'ont pas diminué de manière significative, ce qui suggère une résistance des oocystes à la phagocytose. Une diminution temporaire de l'infectivité des oocystes a été observée en présence d'A. castellanii. L'effet de ces interactions sur l'infectiosité de C. parvum est particulièrement intéressant. La condition biofilm pourrait favoriser la persistance ou même la prolifération des oocystes de C. parvum au fil du temps. Cette étude a démontré des interactions entre C. parvum et amibes libres. Une meilleure connaissance des mécanismes impliqués dans la diminution de l'infectiosité des oocystes en présence d'A. castellanii pourrait faciliter le développement de nouvelles approches thérapeutiques.


Assuntos
Amoeba , Criptosporidiose , Cryptosporidium parvum , Cryptosporidium , Animais , Surtos de Doenças , Oocistos
8.
PLoS One ; 17(4): e0267103, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35421188

RESUMO

Non-Human Primates (NHPs) harbor Cryptosporidium genotypes that can infect humans and vice versa. NHPs Chlorocebus aethiops and Colobus guereza and humans have overlapping territories in some regions of Ethiopia, which may increase the risk of zoonotic transmission of Cryptosporidium. This cross-sectional study examined the molecular prevalence and subtypes of Cryptosporidium spp. from 185 fecal samples of Chlorocebus aethiops and Colobus guereza in rural and urban areas in Ethiopia. Samples were tested for Cryptosporidium infection using nested polymerase chain reaction (PCR), and subtypes were determined by sequencing a fragment of the 60-kDa glycoprotein gene (gp60). Of the 185 samples, fifty-one (27.56%) tested positive for Cryptosporidium infection. The species detected were C. parvum (n = 34), C. hominis (n = 12), and C. cuniculus (n = 3). Mixed infection with C. parvum and C. hominis were detected in 2 samples. Four C. hominis family subtypes (Ia, Ib, Id, and Ie) and one C. parvum family subtype (IIa) were identified. C. hominis IaA20 (n = 7) and C. parvum IIaA17G1R1 (n = 6) were the most prevalent subtypes detected. These results confirm that Chlorocebus aethiops and Colobus guereza can be infected with diverse C. parvum and C. hominis subtypes that can also potentially infect humans. Additional studies could help to understand the role of NHPs in the zoonotic transmission of Cryptosporidium in Ethiopia.


Assuntos
Criptosporidiose , Cryptosporidium , Animais , Chlorocebus aethiops , Colobus , Estudos Transversais , Criptosporidiose/epidemiologia , Cryptosporidium/genética , Etiópia/epidemiologia , Fezes , Variação Genética , Genótipo , Primatas
9.
Pathogens ; 11(8)2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-36015058

RESUMO

Background. Nowadays, most of the C. parvum and C. hominis epidemiological studies are based on gp60 gene subtyping using the Sanger sequencing (SgS) method. Unfortunately, SgS presents the limitation of being unable to detect mixed infections. Next-Generation Sequencing (NGS) seems to be an interesting solution to overcome SgS limits. Thus, the aim of our study was to (i) evaluate the reliability of NGS as a molecular typing tool for cryptosporidiosis, (ii) investigate the genetic diversity of the parasite and the frequency of mixed infections, (iii) assess NGS usefulness in Cryptosporidium sp. outbreak investigations, and (iv) assess an interpretation threshold of sequencing data. Methods. 108 DNA extracts from positive samples were sequenced by NGS. Among them, two samples were used to validate the reliability of the subtyping obtained by NGS and its capacity to detect DNA mixtures. In parallel, 106 samples from French outbreaks were used to expose NGS to epidemic samples. Results. NGS proved suitable for Cryptosporidium sp. subtyping at the gp60 gene locus, bringing more genetic information compared to SgS, especially by working on many samples simultaneously and detecting more diversity. Conclusions. This study confirms the usefulness of NGS applied to C. hominis and C. parvum epidemiological studies, especially aimed at detecting minority variants.

10.
PLoS Negl Trop Dis ; 16(1): e0010068, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35100286

RESUMO

BACKGROUND: Cryptosporidiosis outbreaks in South America are poorly documented. In March 2018, 51 cases of cryptosporidiosis were reported in Maripasoula, a village located in a remote forest area along the border between Surinam and French Guiana. METHOD: To identify the origin of the epidemic, we performed epidemiological, microbiological, and environmental investigations. Only the cases involving diarrhoea and Cryptosporidium-positive stool were considered as bona fide, while cases involving diarrhoea and close contact with a confirmed case were classified as "possible". RESULTS: We identified 16 confirmed cases and 35 possible ones. Confirmed cases comprised nine children (median age of 18 months, range: 6-21), one immunocompromised adult and six soldiers. One child required a hospitalisation for rehydration. All 16 Cryptosporidium stools were PCR positive, and sequencing of the gp60 gene confirmed only one Cryptosporidium hominis subtype IbA10G2. Tap water consumption was the only common risk factor identified. Contamination of the water network with Cryptosporidium parvum subtype IIdA19G2 was found. CONCLUSION: Water quality is a major public health issue in Amazonian French Guiana, especially for population at risk (children, people with comorbidity, travelers). For them, alternative water supply or treatment should be implemented.


Assuntos
Criptosporidiose/epidemiologia , Cryptosporidium parvum/isolamento & purificação , Água Potável/parasitologia , Doenças Transmitidas pela Água/epidemiologia , Adolescente , Criança , Surtos de Doenças , Fezes/parasitologia , Feminino , Guiana Francesa/epidemiologia , Humanos , Hospedeiro Imunocomprometido , Lactente , Masculino , Estudos Retrospectivos , Rios/parasitologia , Qualidade da Água , Doenças Transmitidas pela Água/parasitologia , Adulto Jovem
11.
Food Waterborne Parasitol ; 27: e00160, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35586547

RESUMO

Cryptosporidium is a known foodborne pathogen, ranked fifth out of 24 among foodborne parasites in terms of importance and a cause of many cryptosporidiosis outbreaks worldwide. In France, very few outbreaks were reported before 2017, and data recently obtained by the Expert Laboratory of the Cryptosporidiosis National Reference Center (CNR-LE-Cryptosporidiosis) have shown that outbreaks are in fact common and frequently underreported. In this work, we aim to report the characteristics of outbreaks detected in France during the period 2017-2020 and present a summary of investigations carried out by the CNR-LE-Cryptosporidiosis. During the study period, there were eleven cryptosporidiosis outbreaks, including three with no identified origin. Among the eight identified outbreaks: six were due to water contamination (five tap water and one recreational water), one was due to direct contact with infected calves, and one was due to consumption of contaminated curd cheese. Among these outbreaks, five of them exceeded one hundred cases. Recent results obtained by the CNR-LE-Cryptosporidiosis revealed the multiannual occurrence of Cryptosporidium outbreaks in France. Waterborne outbreaks were more frequently detected, while foodborne outbreaks which are more difficult to detect were likely underreported.

12.
PLoS Negl Trop Dis ; 16(9): e0010776, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36095017

RESUMO

INTRODUCTION: Contaminated drinking and recreational waters account for most of the reported Cryptosporidium spp. exposures in high-income countries. In June 2017, two successive cryptosporidiosis outbreaks occurred among service members in a military training camp located in Southwest France. Several other gastroenteritis outbreaks were previously reported in this camp, all among trainees in the days following their arrival, without any causative pathogen identification. Epidemiological, microbiological and environmental investigations were carried out to explain theses outbreaks. MATERIAL AND METHODS: Syndromic diagnosis using multiplex PCR was used for stool testing. Water samples (100 L) were collected at 10 points of the drinking water installations and enumeration of Cryptosporidium oocysts performed. The identification of Cryptosporidium species was performed using real-time 18S SSU rRNA PCR and confirmed by GP60 sequencing. RESULTS: A total of 100 human cases were reported with a global attack rate of 27.8%. Cryptosporidium spp. was identified in 93% of stool samples with syndromic multiplex PCR. The entire drinking water network was contaminated with Cryptosporidium spp. The highest level of contamination was found in groundwater and in the water leaving the treatment plant, with >1,000 oocysts per 100 L. The same Cryptosporidium hominis isolate subtype IbA10G2 was identified in patients' stool and water samples. Several polluting activities were identified within the protection perimeters of the water resource. An additional ultrafiltration module was installed at the outlet of the water treatment plant. After several weeks, no Cryptosporidium oocysts were found in the public water supply. CONCLUSIONS: After successive and unexplained gastroenteritis outbreaks, this investigation confirmed a waterborne outbreak due to Cryptosporidium hominis subtype IbA10G2. Our study demonstrates the value of syndromic diagnosis for gastroenteritis outbreak investigation. Our results also highlight the importance of better assessing the microbiological risk associated with raw water and the need for sensitive and easy-to-implement tools for parasite detection.


Assuntos
Criptosporidiose , Cryptosporidium , Água Potável , Gastroenterite , Militares , Animais , Criptosporidiose/epidemiologia , Criptosporidiose/parasitologia , Surtos de Doenças/prevenção & controle , Gastroenterite/epidemiologia , Humanos , Oocistos , RNA Ribossômico 18S , Abastecimento de Água
13.
Microorganisms ; 9(2)2021 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-33498375

RESUMO

Human cryptosporidiosis remains underdiagnosed, and rapid/accurate diagnosis is of clinical importance. Diagnosis of the Cryptosporidium oocyst in stool samples by conventional microscopy is labor-intensive, time-consuming, and requires skillful experience. Thus, we aimed to evaluate the usefulness of a coproantigen enzyme-linked immunosorbent assay (ELISA) test in detecting Cryptosporidium spp. from fecal specimens. For this aim, we evaluated the performances of a commercial ELISA (CoproELISA Cryptosporidium kit, Savyon Diagnostics, Israel) for the detection of Cryptosporidium spp. in random clinical stool samples through a multicenter study. The sensitivity and specificity for coproantigen ELISA were 98.86% and 94.32%, respectively. The coproantigen ELISA results indicate that the simple, rapid, reliable, and standardized immunoassay test is sensitive and specific for routine diagnosis, and may be useful for large-scale epidemiological studies of cryptosporidiosis.

14.
Microorganisms ; 9(2)2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33494236

RESUMO

Cryptosporidium spp. is responsible for several food and waterborne disease outbreaks worldwide. Healthier lifestyles attract consumers to eat, notably, fresh food like fruits and vegetables. The consumption of raw or under-cooked food increases the risk of foodborne transmission of Cryptosporidiosis. The assessment of the consumer's exposure to Cryptosporidium danger is crucial for public health. Still, the standardized method to detect this parasite in fresh leafy greens and berry fruits has only been available since 2016 and suffers from weaknesses. Consequently, in this study, we propose a method with minimum processing steps that combines cell culture and the quantitative PCR (CC-qPCR) for detecting infectious C. parvum oocysts recovered from lamb's lettuce. This CC-qPCR is a rapid and easy method that can detect up to one oocyst, whereas it is undetectable by classic qPCR.

15.
Pathogens ; 10(6)2021 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-34071125

RESUMO

Diagnostic approaches based on PCR methods are increasingly used in the field of parasitology, particularly to detect Cryptosporidium. Consequently, many different PCR methods are available, both "in-house" and commercial methods. The aim of this study was to compare the performance of eight PCR methods, four "in-house" and four commercial methods, to detect Cryptosporidium species. On the same DNA extracts, performance was evaluated regarding the limit of detection for both C. parvum and C. hominis specificity and the ability to detect rare species implicated in human infection. Results showed variations in terms of performance. The best performance was observed with the FTD® Stool parasites method, which detected C. parvum and C. hominis with a limit of detection of 1 and 10 oocysts/gram of stool respectively; all rare species tested were detected (C. cuniculus, C. meleagridis, C. felis, C. chipmunk, and C. ubiquitum), and no cross-reaction was observed. In addition, no cross-reactivity was observed with other enteric pathogens. However, commercial methods were unable to differentiate Cryptosporidium species, and generally, we recommend testing each DNA extract in at least triplicate to optimize the limit of detection.

16.
PLoS One ; 16(6): e0253186, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34115820

RESUMO

Data on the distribution and genotype of Cryptosporidium species is limited in Ethiopia. This study examined the presence and genetic diversity of Cryptosporidium species circulating in Ethiopian human population. Stool samples collected from patients who visited rural (n = 94) and urban (n = 93) health centers in Wurgissa and Hawassa district, respectively, were examined for the presence of Cryptosporidium spp. using microscopy, nested PCR and real-time PCR. To detect infection with PCR, analysis of 18S ribosomal RNA was performed. Subtyping was performed by sequencing a fragment of GP60 gene. The overall prevalence of infection was 46% (n = 86) by microscope and PCR. When 48 (out of 86) PCR positive samples were genotyped, two species were identified: C. parvum (n = 40) and C. hominis (n = 8). When 15 of the 40 C. parvum isolates were subtyped, zoonotic subtypes of IIaA14G1R1 (n = 1), IIaA15G2R1 (n = 1), IIaA16G1R1 (n = 2), IIaA16G3R1 (n = 2), IIaA17G1R1 (n = 1), IIaA19G1R1 (n = 1), IIaA20G1R1 (n = 3), IIaA22G1R1 (n = 1), IIaA22G2R1 (n = 1), IIdA23G1 (n = 1) and IIdA24G1 (n = 1) were identified. When 6 of the 8 C. hominis isolates were subtyped, subtypes IaA20 (n = 5), and IdA21(n = 1) were identified. This study suggests that C. parvum and C. hominis are causes of cryptosporidiosis in human in the Wurgissa district and Hawassa in Ethiopia. Zoonotic transmission might be the main route of transmission.


Assuntos
Criptosporidiose/epidemiologia , Cryptosporidium/genética , Adolescente , Adulto , Fatores Etários , Idoso , Animais , Criança , Criptosporidiose/etiologia , Criptosporidiose/parasitologia , Cryptosporidium parvum/genética , DNA de Protozoário/genética , Etiópia/epidemiologia , Fezes/parasitologia , Feminino , Técnicas de Genotipagem , Humanos , Masculino , Microscopia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prevalência , RNA Ribossômico 18S/genética , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco , Adulto Jovem , Zoonoses/epidemiologia , Zoonoses/parasitologia
17.
Microorganisms ; 9(11)2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34835453

RESUMO

Nowadays, many commercial kits allowing the detection of digestive parasites by DNA amplification methods have been developed, including simplex PCR assays (SimpPCRa) allowing the identification of a single parasite, and multiplex PCR assays (MultPCRa) allowing the identification of several parasites at once. Thus, aimed at improving the diagnosis of intestinal protozoal infections, it is essential to evaluate the performances of these new tools. A total of 174 DNA samples collected between 2007 and 2017 were retrospectively included in this study. Performances of four commercial SimpPCRa (i.e., CerTest-VIASURETM) and three MultPCRa (i.e., CerTest-VIASURETM, FAST-TRACK-Diagnostics-FTD-Stool-ParasiteTM and DIAGENODE-Gastroenteritis/Parasite-panel-ITM) were evaluated for the detection of Cryptosporidium spp., Entamoeba spp., and Giardia intestinalis in stool samples compared to our routinely used in-house SimpPCRa. Globally, the SimpPCRa showed better sensitivity/specificity for the detection of G. intestinalis, E. histolytica, E. dispar, and Cryptosporidium spp. (i.e., 96.9/93.6%; 100/100%; 95.5/100%; and 100/99.3%, respectively), compared to the three commercial MultPCRa tested. All in all, we showed that MultPCRa offer an interesting alternative for the detection of protozoans in stool samples depending on the clinical context.

18.
Parasite ; 27: 57, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33141660

RESUMO

Protozoan parasites of the Cryptosporidium genus cause severe cryptosporidiosis in newborn lambs. However, asymptomatic infections also occur frequently in lambs and ewes. In sheep, the most commonly detected Cryptosporidium species are C. ubiquitum, C. xiaoi and C. parvum. Due to a lack of relevant information about such infections in France, we investigated the situation on five dairy sheep farms in the Pyrénées-Atlantiques Department in south-western France in December 2017. Individual fecal samples were collected from 79 female lambs (5-17 days old) and their mothers (72 ewes). Oocysts were screened using Heine staining before and after Bailenger concentrations. Cryptosporidium species identification and genotyping were performed using real-time PCR and gp60 gene sequencing. No cases of clinical cryptosporidiosis were observed in the 79 lambs. Microscopically, Cryptosporidium spp. oocysts were observed in only one lamb on one farm (prevalence 1.3%) and one ewe on another farm (prevalence 1.4%). By contrast, Cryptosporidium spp. DNA was detected in 17 ewes (prevalence ranging from 10.5% to 50% depending on the farm) and in 36 lambs (prevalence ranging from 0% to 77.8% depending on the farm). Only zoonotic Cryptosporidium parvum IId and IIa genotypes were identified when genotyping was possible. Cryptosporidium ubiquitum and C. xiaoi were detected on one and three farms, respectively. We conclude that healthy young lambs and their mothers during the peripartum period could be a source of environmental contamination with oocysts.


TITLE: Les infections asymptomatiques par Cryptosporidium chez les brebis et les agneaux sont une source de contamination environnementale par les génotypes zoonotiques de Cryptosporidium parvum. ABSTRACT: Les parasites protozoaires du genre Cryptosporidium provoquent une cryptosporidiose sévère chez les agneaux nouveau-nés. Cependant, des infections asymptomatiques surviennent aussi fréquemment chez les agneaux et les brebis. Chez les ovins, les espèces de Cryptosporidium les plus couramment détectées sont C. ubiquitum, C. xiaoi et C. parvum. En raison d'un manque d'informations pertinentes sur ces infections en France, nous avons enquêté sur la situation de cinq élevages ovins laitiers des Pyrénées-Atlantiques en décembre 2017. Des échantillons fécaux individuels ont été collectés sur 79 agnelles (5 à 17 jours) et leurs mères (72 brebis). Les oocystes ont été criblés en utilisant une coloration Heine avant et après concentration par la technique de Bailenger. L'identification et le génotypage des espèces de Cryptosporidium ont été réalisés à l'aide de la PCR en temps réel et du séquençage du gène gp60. Aucun cas de cryptosporidiose clinique n'a été observé chez les 79 agneaux. Au microscope, les oocystes de Cryptosporidium spp. n'ont été observés que chez un agneau dans une ferme (prévalence 1,3 %) et chez une brebis dans une autre ferme (prévalence 1,4 %). En revanche, de l'ADN de Cryptosporidium spp. a été détecté chez 17 brebis (prévalence allant de 10,5 % à 50 % selon les fermes) et chez 36 agneaux (prévalence variant de 0 % à 77,8 % selon les fermes). Seuls les génotypes zoonotiques de Cryptosporidium parvum IId et IIa ont été identifiés lorsque le génotypage était possible. Cryptosporidium ubiquitum et C. xiaoi ont été détectés respectivement dans une et trois fermes. Nous concluons que les jeunes agneaux en bonne santé et leurs mères, autour de l'agnelage, pourraient être une source de contamination environnementale par les oocystes.


Assuntos
Infecções Assintomáticas , Criptosporidiose , Cryptosporidium parvum , Genótipo , Doenças dos Ovinos , Animais , Criptosporidiose/epidemiologia , Criptosporidiose/parasitologia , Cryptosporidium parvum/genética , Fezes , Feminino , França/epidemiologia , Prevalência , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia
19.
Microorganisms ; 8(9)2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32899825

RESUMO

Cryptosporidiosis is currently recognized worldwide as a leading cause of moderate to severe diarrhea. In Europe, large water- and foodborne outbreaks have been reported, highlighting the widespread distribution of the parasite and its important health impact. Surveillance networks have been progressively set up and the aim of this study was to present recent epidemiological data obtained in France from 2017 to 2019 by the National Reference Center-Expert Laboratory of cryptosporidiosis (Centre National de Référence-Laboratoire Expert cryptosporidioses CNR-LE). Data were obtained from online reports of volunteer network participants and stools were sent to the CNR-LE for species identification and GP60 genotyping. During this period, data from 750 online reports were available. Cryptosporidiosis occurred predominantly in young children (<5 years old) and in young adults, especially during late summer. Most patients were immunocompetent (60%), and deaths were reported only in immunocompromised patients. Cryptosporidium parvum was largely predominant (72% of cases) over C. hominis (24%) and some other uncommon species. C. parvum GP60 subtypes IIa and IId were the most represented, which suggests frequent zoonotic transmission. For C. hominis, subtypes IbA10G2 and IaA22R2 were predominant.

20.
Microorganisms ; 8(9)2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32971858

RESUMO

BACKGROUND: Nowadays, many commercial kits allow the detection of Cryptosporidium sp. in stool samples after deoxyribonucleic acid (DNA) extraction. Protocols of stool pretreatment have been proposed to optimize oocysts' DNA extraction. Among them, mechanical grinding was reported to improve the performance of Cryptosporidium oocysts' DNA extraction. METHODS: A multicenter comparative study was conducted within the framework of the French National Reference Center-Expert Laboratory for Cryptosporidiosis. Six extraction systems (i.e., manual or automated) associated with various mechanical pretreatment protocols, were compared for the Cryptosporidium parvum oocyst' DNA extraction, before amplification using the same real-time PCR method targeting. RESULTS: The sensitivity of real-time PCR assay was unequally impacted by the pretreatment/extraction protocol. We observed significant differences for the lowest concentrations of C. parvum oocysts (i.e., 0-94.4% and 33.3-100% respectively for 10 and 50 oocysts/mL). All in all, the protocol using Quick DNA Fecal/Soil Microbe-Miniprep® manual kit showed the best performances. In addition, optimal performances of mechanical pretreatment were obtained by combining a grinding duration of 60 s with a speed of 4 m/s using Fastprep24® with Lysing Matrix E®. CONCLUSIONS: Sample pretreatment, as well as the extraction method, needs to be properly adapted to improve the diagnostic performances of the C. parvum DNA amplification methods.

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