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Global changes in climate are contributing to modified Phlebotomine sand fly presence and activity, and the distribution of the pathogens they transmit (e.g., Leishmania and Phlebovirus), and are leading to their possible extension toward northern France. To predict the evolution of these pathogens and control their spread, it is essential to identify and characterize the presence and abundance of potential vectors. However, there are no recent publications describing sand fly species distribution in France. Consequently, we carried out a systematic review to provide distribution and abundance maps over time, along with a simplified dichotomous key for species in France. The review adhered to PRISMA guidelines, resulting in 172 relevant capture reports from 168 studies out of the 2646 documents retrieved, of which 552 were read and 228 analyzed. Seven species were recorded and categorized into three groups based on their abundance: low abundance species, abundant but little-studied species, and abundant vector species. Sand flies are certainly present throughout France but there is a greater diversity of species in the Mediterranean region. Phlebotomus perniciosus and Ph. ariasi are the most abundant and widely distributed species, playing a role as vectors of Leishmania. Sergentomyia minuta, though very abundant, remains under-studied, highlighting the need for further research. Phlebotomus papatasi, Ph. perfiliewi, Ph. sergenti, and Ph. mascittii are present in low numbers and are less documented, limiting understanding of their potential role as vectors. This work provides the necessary basis for comparison of field data generated in the future.

Toxoplasmosis is a zoonosis that infects humans and other warm-blooded animals worldwide; prevalence and clinical severity vary by geographic area (1). After primary infection, the parasite persists lifelong within dormant [...]

Molecular biology has been gaining more importance in parasitology. Recently, a commercial multiplex PCR assay detecting helminths was marketed: the Allplex™ GI-Helminth(I) Assay. It targets Ancylostoma spp., Ascaris spp., Enterobius vermicularis, Hymenolepis spp., Necator americanus, Strongyloides spp., Taenia spp. and Trichuris trichiura, but also the two most common microsporidia genera in human health, i.e. Enterocytozoon spp. and Encephalitozoon spp. This study aimed to evaluate and compare the Allplex™ GI-Helminth(I) Assay to classical diagnostic methods, based on a cohort of 110 stool samples positive for helminths (microscopy) or for microsporidia (PCR). Samples were stored at −80 °C until analysis by the Allplex™ GI-Helminth(I) Assay. False-negatives were re-tested with bead-beating pretreatment. Without mechanical lysis, concordance and agreement between microscopy and Allplex™ GI-Helminth(I) Assay ranged from 91% to 100% and from 0.15 to 1.00, respectively depending on the target. Concordance was perfect for Taenia spp. (n = 5) and microsporidia (n = 10). False-negative results were observed in 54% (6/13), 34% (4/11) and 20% (7/35) of cases, for hookworms, E. vermicularis and Strongyloides spp. detection, respectively. For these targets, pretreatment improved the results, but only slightly. Trichuris trichiura detection was critically low without pretreatment, as only 9% (1/11) of the samples were positive, but detection reached 91% (10/11) with bead-beating pretreatment. Mechanical lysis was also needed for Ascaris spp. and Hymenolepis spp. to reduce false-negative results from 1/8 to 1/21, respectively, to none for both. Overall, with an optimized extraction process, the Allplex™ GI-Helminth(I) Assay allows the detection of numerous parasites with roughly equivalent performance to that of microscopy, except for hookworms.

Chronic infection with Toxoplasma gondii is attested by the detection of specific anti-Toxoplasma IgG. A wide panel of serologic methods is currently marketed, and the most suitable method should be chosen according to the laboratory resources and the screened population. This systematic review of evaluation studies aimed at establishing an overview of the performances, i.e. sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of marketed anti-Toxoplasma IgG assays, and discussing their technical characteristics to guide further choice for routine diagnostic use. According to PRISMA guidelines, the search performed in PubMed and Web of Science databases recovered 826 studies, of which 17 were ultimately included. Twenty commercial anti-Toxoplasma IgG assays were evaluated, in comparison with an accepted reference method. Most of them were enzyme-immunoassays (EIAs, n = 12), followed by agglutination tests (n = 4), immunochromatographic tests (n = 3), and a Western-Blot assay (WB, n = 1). The mean sensitivity of IgG assays ranged from 89.7% to 100% for standard titers and from 13.4% to 99.2% for low IgG titers. A few studies pointed out the ability of some methods, especially WB to detect IgG early after primary infection. The specificity of IgG assays was generally high, ranging from 91.3% to 100%; and higher than 99% for most EIA assays. The PPV was not a discriminant indicator among methods, whereas significant disparities (87.5%–100%) were reported among NPVs, a key-parameter assessing the ability to definitively rule out a Toxoplasma infection in patients at-risk for opportunistic infections.

Strongyloides stercoralis serology is a sensitive method for strongyloidiasis diagnosis, but it is prone to cross-reactions with other helminthiases. This four-year retrospective study aimed at estimating the performance of the Bordier IVD® Strongyloides ratti ELISA assay in a non-endemic country (France). The study included all patients tested for strongyloidiasis in our center between 2015 and 2019, by both serology and stool examination. Cases were defined using an algorithm considering serological results, microscopic examination of stools, and other biological, clinical or epidemiological data. The study included 805 stools from 341 patients (70% migrants, 20% travelers, 10% without travel to a highly endemic area). Thirty patients (8.8%) had positive serology, 9 had microscopically proven strongyloidiasis, and 11 and 10 were classified as probable and possible strongyloidiasis, respectively. Performances of microscopy and serology were compared, considering proven and probable strongyloidiasis as true infections. The sensitivity, specificity, positive predictive value and negative predictive value of serology were 100%, 97%, 67% and 100%, respectively, and those of microscopic examination of stools were 45% (p

Pneumocystis pneumonia (PCP) is the most frequent fungal opportunistic infection defining AIDS in HIV-infected patients, and is of growing importance in HIV-negative patients. In this latter category of patients, the diagnosis mainly relies on real-time polymerase chain reaction (qPCR) detection of Pneumocystis jirovecii (Pj) on respiratory samples. The PneumoGenius® kit (PathoNostics) allows the simultaneous detection of Pj mitochondrial large subunit (mtLSU) and dihydropteroate synthase (DHPS) polymorphisms, which could be of interest to anticipate therapeutic failure. This study aimed at evaluating its clinical performance on 251 respiratory specimens (239 patients), (i) for P. jirovecii detection in clinical samples, and (ii) for DHPS polymorphisms detection in circulating strains. Patients were classified according to modified European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG) criteria, as having proven PCP (n = 62), probable PCP (n = 87), Pneumocystis colonization (n = 37), and no PCP (n = 53). Compared with in-house qPCR, the sensitivity of PneumoGenius® assay for P. jirovecii detection reached 91.9% (182/198), the specificity was excellent (100%, 53/53) and the global concordance was 93.6% (235/253). A total of four diagnoses of proven/probable PCP were missed by the PneumoGenius® assay, reaching a 97.5% sensitivity (157/161) in this sub-group. The 12 other 'false–negative' results were obtained in patients diagnosed as colonized using the in-house PCR. DHPS genotyping was successful for 147/182 samples with PneumoGenius® and revealed dhps mutation in 8 samples, which were all confirmed by sequencing. In conclusion, PneumoGenius® assay missed the detection of low-burden PCP. This lower sensitivity for PCP diagnosis can be balanced by a higher specificity (P. jirovecii colonization less frequently detected) and the efficient detection of DHPS hot spot mutations. Lay Summary: The diagnosis of Pneumocystis pneumonia (PCP) relies on DNA detection of P. jirovecii in respiratory samples. In this study, we show that the commercial assay PneumoGenius® has a lower sensitivity than our in-house qPCR for PCP diagnosis, but provides accurate results for DHPS genotyping. [ABSTRACT FROM AUTHOR]