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1.
Curr Issues Mol Biol ; 46(5): 3810-3821, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38785505

RESUMO

French Guiana, located in the Guiana Shield, is a natural reservoir for many zoonotic pathogens that are of considerable medical or veterinary importance. Until now, there has been limited data available on the description of parasites circulating in this area, especially on protozoan belonging to the phylum Apicomplexa; conversely, the neighbouring countries describe a high parasitic prevalence in animals and humans. Epidemiological surveillance is necessary, as new potentially virulent strains may emerge from these forest ecosystems, such as Amazonian toxoplasmosis. However, there is no standard tool for detecting protozoa in wildlife. In this study, we developed Meat-Borne-Parasite, a high-throughput meta-barcoding workflow for detecting Apicomplexa based on the Oxford Nanopore Technologies sequencing platform using the 18S gene of 14 Apicomplexa positive samples collected in French Guiana. Sequencing reads were then analysed with MetONTIIME pipeline. Thanks to a scoring rule, we were able to classify 10 samples out of 14 as Apicomplexa positive and reveal the presence of co-carriages. The same samples were also sequenced with the Illumina platform for validation purposes. For samples identified as Apicomplexa positive by both platforms, a strong positive correlation at up to the genus level was reported. Overall, the presented workflow represents a reliable method for Apicomplexa detection, which may pave the way for more comprehensive biomonitoring of zoonotic pathogens.

2.
PLoS Negl Trop Dis ; 16(10): e0010745, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36206322

RESUMO

BACKGROUND: In France, leishmaniasis is endemic in the Mediterranean region, in French Guiana and to a lesser extent, in the French West Indies. This study wanted to provide an updated picture of leishmaniasis epidemiology in metropolitan France and in its overseas territories. METHODOLOGY/PRINCIPAL FINDINGS: Leishmaniasis cases were collected by passive notification to the French National Reference Centre for Leishmaniases (NRCL) in Montpellier from 1998 to 2020 and at the associated Centre in Cayenne (French Guiana) from 2003 to 2020. In metropolitan France, 517 autochthonous leishmaniasis cases, mostly visceral forms due to Leishmania infantum (79%), and 1725 imported cases (French Guiana excluded), mainly cutaneous leishmaniasis from Maghreb, were recorded. A slight decrease of autochthonous cases was observed during the survey period, from 0.48 cases/100,000 inhabitants per year in 1999 (highest value) to 0.1 cases/100,000 inhabitants per year in 2017 (lowest value). Conversely, imported cases increased over time (from 59.7 in the 2000s to 94.5 in the 2010s). In French Guiana, 4126 cutaneous and mucocutaneous leishmaniasis cases were reported from 2003 to 2020. The mean incidence was 103.3 cases per 100,000 inhabitants/year but varied in function of the year (from 198 in 2004 to 54 in 2006). In Guadeloupe and Martinique (French West Indies), only sporadic cases were reported. CONCLUSIONS/SIGNIFICANCE: Because of concerns about disease expansion and outbreaks in other Southern Europe countries, and leishmaniasis monitoring by the NRCL should be continued and associated with a more active surveillance.


Assuntos
Leishmania infantum , Leishmaniose Cutânea , Leishmaniose Mucocutânea , Humanos , França/epidemiologia , Índias Ocidentais
3.
PLoS One ; 16(9): e0257169, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34516569

RESUMO

A prospective study was conducted among different intra and extra-hospital populations of French Guiana to evaluate the performance of saliva testing compared to nasopharyngeal swabs. Persons aged 3 years and older with mild symptoms suggestive of COVID-19 and asymptomatic persons with a testing indication were prospectively enrolled. Nasopharyngeal and salivary samples were stored at 4°C before analysis. Both samples were analyzed with the same Real-time PCR amplification of E gene, N gene, and RdRp gene. Between July 22th and October 28th, 1159 persons were included, of which 1028 were analyzed. When only considering as positives those with 2 target genes with Ct values <35, the sensitivity of RT-PCR on saliva samples was 100% relative to nasopharyngeal samples. Specificity positive and negative predictive values were above 90%. Across a variety of cultures and socioeconomic conditions, saliva tests were generally much preferred to nasopharyngeal tests and persons seemed largely confident that they could self-sample. For positive patients defined as those with the amplification of 2 specific target genes with Ct values below 35, the sensitivity and specificity of RT-PCR on saliva samples was similar to nasopharyngeal samples despite the broad range of challenging circumstances in a tropical environment.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , Saliva/virologia , Adolescente , Adulto , Idoso , Teste de Ácido Nucleico para COVID-19/normas , Criança , Pré-Escolar , Feminino , Guiana Francesa , Hospitais/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Aceitação pelo Paciente de Cuidados de Saúde , Sensibilidade e Especificidade , Clima Tropical
4.
Am J Trop Med Hyg ; 104(6): 2091-2096, 2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33939643

RESUMO

Cutaneous leishmaniasis (CL) is firmly established in South America. We aimed to assess the detection of IgG antibodies against 14 and/or 16 kDa antigens by immunoblot (IB) for CL serological diagnosis in French Guiana, an area where many endemic pathogens could interfere with it. This study was performed retrospectively on sera from 141 patients at the Cayenne tertiary hospital: 30 were patients with confirmed CL, 71 were diagnosed with various other endemic pathogens, 11 were diagnosed with an autoimmune disease, and 29 controls had no history of CL. Antibodies bound to the 14 and/or 16 kDa antigens in 27 of the 30 CL patients' sera and in 39 of the 111 non-CL patients' sera (26 from the infectious diseases group, four from the autoimmune diseases group, and nine from the dermatology department). The method tested showed a high sensitivity (90%) and a low specificity (66%), and a diagnosis odds ratio of 17.5 (95% CI [4.6-78.0]). This IB may be helpful to exclude the diagnosis of CL, prompting physicians to look for another diagnosis in the case of a negative IB.


Assuntos
Anticorpos Antiprotozoários/sangue , Immunoblotting/métodos , Immunoblotting/normas , Imunoglobulina G/sangue , Leishmania/imunologia , Leishmaniose Cutânea/diagnóstico , Adolescente , Adulto , Antígenos de Protozoários/imunologia , Doenças Endêmicas , Feminino , Guiana Francesa , Humanos , Leishmania/classificação , Leishmaniose Cutânea/sangue , Leishmaniose Cutânea/imunologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Centros de Atenção Terciária/estatística & dados numéricos , Adulto Jovem
5.
J Clin Microbiol ; 59(2)2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33148706

RESUMO

Recent studies have highlighted the interest in noninvasive sampling procedures coupled with real-time PCR methods for the detection of Leishmania species in South America. In French Guiana, the sampling method still relied on skin biopsies. Noninvasive protocols should be tested on a large annual cohort to improve routine laboratory diagnosis of cutaneous leishmaniasis. Therefore, we evaluated the performance of a new Leishmania detection and species identification protocol involving cotton swabs and SYBR green-based real-time PCR of the Hsp70 gene, coupled with Sanger sequencing. Between May 2017 and May 2018, 145 patients with ulcerated lesions compatible with cutaneous leishmaniasis were included in the study at the Cayenne Hospital and its remote health centers. Each patient underwent scrapings for a smear, skin biopsies for parasite culture and PCR-restriction fragment length polymorphism (RFLP) (RNA polymerase II), and sampling with a cotton swab for SYBR green-based PCR. The most accurate diagnostic test was the SYBR green-based PCR on swab samples, showing 98% sensitivity. The mean PCR cycle threshold (CT ) was 24.4 (minimum CT , 17; maximum CT , 36) and was <35 in 97.6% of samples. All samples positive by SYBR green-based real-time PCR were successfully identified at the species level by DNA sequencing. This new method should be considered for routine diagnosis of cutaneous leishmaniasis in South America and especially for remote areas, since noninvasive collection tools are easier to use and require fewer precautions for transportation.


Assuntos
Leishmaniose Cutânea , DNA de Protozoário/genética , Guiana Francesa , Humanos , Leishmaniose Cutânea/diagnóstico , Polimorfismo de Fragmento de Restrição , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade , América do Sul
6.
PLoS Negl Trop Dis ; 14(8): e0008380, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32797078

RESUMO

In French Guiana, five species are associated with Cutaneous Leishmaniasis (CL). Though infections with Leishmania guyanensis, L. (V.) braziliensis and L. (L.) amazonensis have been extensively described, there are few available clinical and genetic data on L. (V.) lainsoni and L. (V.) naiffi. We determined the clinical and epidemiological features of all cases of CL due to L. (V.) naiffi and L. (V.) lainsoni diagnosed in French Guiana between 2003 and 2019. Phylogenetic analysis was performed by sequencing a portion of HSP70 and cyt b genes. Five cases of L. naiffi and 25 cases of L. lainsoni were reported. Patients infected by L. (V.) lainsoni were usually infected on gold camps, mostly along the Maroni river (60%), while L. naiffi was observed in French patients infected on the coast (100%). A high number of pediatric cases (n = 5; 20%) was observed for L. (V.) lainsoni. A mild clinical course was observed for all cases of L. (V.) naiffi. HSP70 and cyt b partial nucleotide sequence analysis revealed different geographical clusters within L. (V.) naiffi and L. (V.) lainsoni but no association were found between phylogenetic and clinical features. Our data suggest distinct socio-epidemiological features for these two Leishmania species. Patients seem to get infected with L. (V.) naiffi during leisure activities in anthropized coastal areas, while L. (V.) lainsoni shares common features with L. (V.) guyanensis and braziliensis and seems to be acquired during professional activities in primary forest regions. Phylogenetic analysis has provided information on the intraspecific genetic variability of L. (V.) naiffi and L. (V.) lainsoni and how these genotypes are distributed at the geographic level.


Assuntos
Leishmania/classificação , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Citocromos b/genética , Feminino , Guiana Francesa/epidemiologia , Proteínas de Choque Térmico HSP70/genética , Humanos , Lactente , Leishmania/genética , Leishmania/patogenicidade , Leishmaniose Cutânea/patologia , Atividades de Lazer , Masculino , Pessoa de Meia-Idade , Mineração , Doenças Negligenciadas , Filogenia , Estudos Retrospectivos , Análise de Sequência de DNA
7.
Parasite ; 26: 60, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31549631

RESUMO

BACKGROUND: Toxoplasma gondii is an obligate intracellular protozoan parasite of warm-blooded vertebrates. Most infections in immunocompetent patients are asymptomatic. However, since 2000s, strains with particular genetic profiles that differ from the known clonal type (type I, II, III), have been described. In French Guiana, these strains are highly pathogenic in immunocompetent patients. They have defined a new clinical entity called Amazonian Toxoplasmosis. The present study aims to further improve our knowledge on the pathogenicity of these Amazonian T. gondii strains in comparison with three reference strains using Swiss strain mice. With these data, we tried to establish a predictive virulence score to classify these strains, but also to correlate this virulence with the severity of the disease in infected patients. RESULTS: All the virulence indicators revealed that the Amazonian strains isolated in French Guiana presented a high virulence profile, but lower than the highly virulent type I reference RH strain. The findings reveal differences in virulence between human and animal strains, but also between anthropized and wild strains. CONCLUSION: In addition to being a clinically relevant animal model of Amazonian Toxoplasmosis, this model could also provide a solid experimental basis for future studies aiming to investigate the underlying mechanisms of Amazonian Toxoplasmosis disease.


TITLE: Virulence des souches atypiques de Toxoplasma gondii isolées en Guyane française chez un modèle murin. ABSTRACT: Contexte. Toxoplasma gondii est un parasite protozoaire intracellulaire obligatoire des vertébrés à sang chaud. La plupart des infections chez les patients immunocompétents sont asymptomatiques. Cependant, depuis les années 2000, des souches avec des profils génétiques particuliers qui diffèrent du type clonal connu (type I, II, III) ont été décrites. En Guyane française, ces souches sont hautement pathogènes chez les patients immunocompétents. Elles ont défini une nouvelle entité clinique appelée Toxoplasmose Amazonienne. La présente étude vise à approfondir nos connaissances sur le pouvoir pathogène de ces souches amazoniennes de T. gondii par rapport à 3 souches de référence en utilisant des souris de souche Swiss. Avec ces données, nous avons tenté d'établir un score de virulence prédictif pour classer ces souches mais également de corréler cette virulence avec la gravité de la maladie chez les patients infectés. Résultats. Tous les indicateurs de virulence ont révélé que les souches amazoniennes isolées en Guyane française présentaient une virulence élevée mais plus faible que la souche de référence RH très virulente de type I. Les résultats ont mis en évidence les différences de virulence entre les souches humaines et animales mais aussi entre les souches anthropisées et les souches sauvages. Conclusion. En plus d'être un modèle animal cliniquement pertinent de la toxoplasmose amazonienne, ce modèle pourrait également fournir une base expérimentale solide à de futurs travaux qui chercheront à approfondir les mécanismes sous-jacents de la toxoplasmose amazonienne.


Assuntos
Toxoplasma/genética , Toxoplasma/patogenicidade , Toxoplasmose Animal/parasitologia , Animais , Modelos Animais de Doenças , Guiana Francesa , Variação Genética , Genótipo , Humanos , Camundongos , Repetições de Microssatélites , Filogenia , Organismos Livres de Patógenos Específicos , Toxoplasma/isolamento & purificação , Virulência
8.
Int J Dermatol ; 58(11): 1323-1328, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31524286

RESUMO

BACKGROUND: American cutaneous leishmaniasis (ACL) is endemic in French Guiana. Its epidemiology is evolving, notably because of immigration, anthropization of natural areas, and new microbiological methods. Our first objective was to update epidemiological data. Our second objective was to look for risk factors of ACL. METHODS: This multicentric study was conducted from October 2017 to June 2018 in French Guiana. Patients with suspicion of mucocutaneous leishmaniasis were included in case of positive smear, culture, or PCR-RFLP on skin biopsy. RESULTS: One hundred and twenty-three patients met the inclusion criteria. Among those patients, 59.3% were Brazilian, mostly gold miners. Most of them (58%) were between 16 and 40 years old, and 69% were male. A large proportion of patients lived in traditional wooden houses (51%). Patients living in coastal towns were usually infected during trips to the primary forest (60%) and had a shorter time to diagnosis than workers of the hinterland. Among environmental risk factors, the presence of a water spring (40%) and dogs around houses (40%) were frequently reported. Leishmania guyanensis represented 80% of cases, followed by Leishmania braziliensis (6%), Leishmania naiffi (2%), and Leishmania amazonensis (1%). CONCLUSIONS: Gold mining and trips to the primary forest represent high-risk situations for ACL in French Guiana, where the population of infected patients is dominated by Brazilian immigrants. Possible environmental risk factors such as the presence of dogs, water sources, and traditional wooden houses require further investigation.


Assuntos
Doenças Endêmicas , Leishmaniose Cutânea/epidemiologia , Pele/parasitologia , Adolescente , Adulto , Idoso , Biópsia , Exposição Ambiental/efeitos adversos , Feminino , Florestas , Guiana Francesa/epidemiologia , Ouro , Humanos , Leishmania braziliensis/isolamento & purificação , Leishmania guyanensis/isolamento & purificação , Leishmania mexicana/isolamento & purificação , Leishmaniose Cutânea/parasitologia , Masculino , Pessoa de Meia-Idade , Mineração/estatística & dados numéricos , Fatores de Risco , Adulto Jovem
9.
Am J Trop Med Hyg ; 101(4): 848-850, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31436152

RESUMO

Strongyloides stercoralis and human T-lymphotropic virus 1 (HTLV-1) coinfections have been extensively reported in the literature, but the diagnosis and treatment of strongyloidiasis remains a challenge, particularly in HTLV-1 carriers. Our objectives were to evaluate the efficacy of a new PCR method for the detection of S. stercoralis in HTLV-1-positive patients. Stools were collected over a 1-year period across the endemic region of French Guiana, including remote forest areas. Two systems of real-time PCR were then used comparatively, with small subunit and specific repeat as respective targets, and compared with the results of microscopic examinations. One-hundred and twelve stool samples were included. Twenty-seven patients (24.1%) presented a positive HTLV-1 serology. The overall prevalence of strongyloidiasis among the 112 patients was 30% with small-subunit PCR and 11.6% with microscopic examinations. In the seropositive population, all tested stools were negative, whereas 51.2% were positive using small-subunit PCR. Thus, PCR allowed a much-improved sensitivity, particularly in HTLV-1 carriers. Among the two systems investigated, small subunit yielded better results than specific repeat PCR, with prevalence rates in HTLV-1 carriers of 51.2% and 22.2%, respectively. Therefore, PCR should be considered as a useful tool for the diagnosis of strongyloidiasis, particularly in HTLV-1 carriers who often present a light parasitic load due to erratic administration of anthelmintic drugs.


Assuntos
Coinfecção , Infecções por HTLV-I/complicações , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Strongyloides stercoralis/isolamento & purificação , Estrongiloidíase/diagnóstico , Animais , Anti-Helmínticos/uso terapêutico , Sondas de DNA/genética , Fezes/parasitologia , Guiana Francesa/epidemiologia , Infecções por HTLV-I/epidemiologia , Infecções por HTLV-I/virologia , Humanos , Prevalência , Sensibilidade e Especificidade , Strongyloides stercoralis/genética , Estrongiloidíase/complicações , Estrongiloidíase/epidemiologia , Estrongiloidíase/parasitologia
10.
Trop Med Health ; 45: 5, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28265182

RESUMO

BACKGROUND: The development of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique for species identification among patients presenting leishmaniasis allowed to better determine the main circulating species in French Guiana. METHODS: A descriptive study of the Leishmania species was identified, and their spatiotemporal distribution was conducted using patient records between 2006 and 2013, with 1017 new cases of leishmaniasis diagnosed. Identification was realized by PCR-RFLP on 745 cases. RESULTS: The average proportions for different species were 86.2% for Leishmania (Vianna) guyanensis; 9.7% for Leishmania (Vianna) braziliensis; 2.8% for Leishmania (Leishmania) amazonensis; and 1.3% for Leishmania (Vianna) lainsoni, and no case of Leishmania (Vianna) naiffi was identified. Over this period, the proportion of cases due to L. (V.) braziliensis seemed to increase from 8.9% in 2006 to 13.0% in 2013 notably near the gold mining zones. CONCLUSIONS: The use of molecular tools has transformed the view of the local epidemiology of cutaneous leishmaniasis in French Guiana.

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