Features of cryptococcosis among 652 HIV-seronegative individuals in France: a cross-sectional observational study (2005-2020)

OBJECTIVES

We aimed to describe features and outcomes of cryptococcosis among HIV-seronegative individuals in a large surveillance network for cryptococcosis in France.

METHODS

We included incident cases of cryptococcosis in HIV-seronegative individuals from 2005 to 2020. We compared patient characteristics, disease presentations, cryptococcal antigen results, and induction antifungal treatments according to underlying disease. We examined factors associated with 90-day mortality. Among patients with disseminated infections, we investigated whether receipt of flucytosine and polyene combination was associated with lower mortality.

RESULTS

Among 652 individuals, 209 (32.1%) had malignancy, 130 (19.9%) were solid-organ transplant recipients, 204 (31.3%) had other immunocompromising conditions, and 109 (16.7%) had no reported underlying factor. The commonest presentations were disseminated infections (63.3%, 413/652) and isolated pulmonary infections (25.3%, 165/652). Solid-organ transplant patients were most likely to have disseminated infections and a positive serum cryptococcal antigen result. Patients with malignancy were older and less likely to receive a flucytosine-containing regimen for disseminated infections than others (58.7%, 78/133 vs. 73.2%, 194/265; p 0.029). The crude 90-day case-fatality ratio was 27.2% (95% CI, 23.5%-31.1%). Age ≥60 years (aOR: 2.75 [1.78-4.26]; p < 0.001), meningitis/fungaemia (aOR: 4.79 [1.80-12.7]; p 0.002), and malignancy (aOR: 2.4 [1.14-5.07]; p 0.02) were associated with higher 90-day mortality. Receipt of flucytosine and polyene combination was associated with lower 90-day mortality (aOR: 0.40 [0.23-0.71]; p 0.002) in multivariable analysis and inverse probability of treatment weighted analysis (aOR: 0.45 [0.25-0.80]; p 0.006).

DISCUSSION

HIV-seronegative individuals with cryptococcosis comprise a wide range of underlying conditions with different presentations and outcomes, requiring a tailored approach to diagnosis and management.

Knowledge, attitudes and practices of French university students towards COVID-19 prevention-are health students better?

During the COVID-19 outbreak in 2020, public health measures (PHM) were implemented to prevent the spread of SARS-CoV-2. At university, we wondered whether health students would be more likely to comply with these safety measures against infectious disease transmission compared to other students. Thus, we collected 1 426 university students' responses to an online anonymous survey to describe their knowledge, attitudes and practices (KAP) of COVID-19 prevention measures and to compare the opinions and practices of health students and science students at the same university of Rouen Normandy (France). A higher proportion of science students (84.6%) compared to health students (73.9%) reported knowledge of the university's COVID-19 protocol, p<0.001. However, the health students compared to science students reported a higher compliance with PHM at home (91.4% vs 88.0%) and at university (94.1% vs 91.1%). In a multiple regression analysis, after adjustment for age, sex and university department, factors associated with higher compliance with PHM were knowledge of the university's COVID-19 protocol and a high perceived efficacy of PHM. A SARS-CoV-2 PCR result was not predictive of compliance with PHM. The results of this online survey in French students show a high level of knowledge and practices of COVID-19 prevention Although their performances could still be improved by training, the good results of health students regarding knowledge, attitudes and practices are encouraging as these students could be an added backup force to fight against viral pandemics.

Invasive fungal diseases in patients with autoimmune diseases: a case series from the French RESSIF network

OBJECTIVES

We aimed to describe patients with autoimmune diseases (AID) developing invasive fungal disease (IFD) and identify factors associated with short-term mortality.

METHODS

We analysed cases of IFD associated with AID from the surveillance network of invasive fungal diseases (Réseau de surveillance des infections fongiques invasives, RESSIF) registry of the French national reference centre for invasive mycoses. We studied association of AID-specific treatments with 30-day mortality. We analysed total lymphocyte and CD4-T cell counts in patients with Pneumocystis jirovecii pneumonia (PCP).

RESULTS

From 2012 to 2018, 549 individuals with IFD and AID were included, mainly with PCP (n=227, 41.3%), fungemia (n=167, 30.4%) and invasive aspergillosis (n=84, 15.5%). Rheumatoid arthritis (RA) and anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitides (AAV) were the most frequent AID in PCP (n=55 and 25, respectively) and invasive aspergillosis (n=15 and 10, respectively), inflammatory bowel diseases (IBDs) were predominant in fungemia (n=36). At IFD diagnosis, 365 (66.5%) patients received glucocorticoids (GCs), 285 (51.9%) immunosuppressants, 42 (7.7%) tumor necrosis factor (TNF)-α blockers, 75 (13.7%) other biologics. Mortality at 30 days was 28.1% (143/508). Fungemia and high-dose GCs were independently associated with higher 30-day mortality. In PCP patients, lymphopenia <1500/mm3 was frequent (132/179, 73.7%) even if CD4+T cell count exceeded 200/mm3 in 56/78 patients (71.8%) (median 472.5/mm3, IQR 160-858).

CONCLUSION

IFD associated with AID occurs primarily in RA, AAV and IBD, especially when treated with GCs and immunosuppressants. Mortality is high, especially for patients on high-dose GCs. Lymphopenia may help identify risk of PCP, but normal CD4+T cell count does not rule out the risk. Further studies are needed to assess the individual risk factors for IFD.

Persistence and survival of Cryptosporidium parvum oocysts on lamb's lettuce leaves during plant growth and in washing conditions of minimally-processed salads

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.

Evaluation of the Bio-Evolution Microsporidia generic and typing real-time PCR assays for the diagnosis of intestinal microsporidiosis

Cases of intestinal microsporidiosis infection are underestimated and affect both immunocompromized and immunocompetent patients. Real-time PCR is superseding microscopic examination for its diagnosis in medical analysis laboratories. However, few manufacturers include microsporidia in their PCR panel for the diagnosis of infectious gastroenteritis. Here, we evaluated the performances of the real-time PCR assays microsporidia generic and microsporidia typing (Bio-Evolution, France) on the Rotor-Gene Q real-time PCR cycler (Qiagen, France). We included 45 negative and 44 positive stool samples for Enterocytozoon bieneusi (n = 34, with various genotypes), Encephalitozoon intestinalis (n = 4), Encephalitozoon hellem (n = 4), and Encephalitozoon cuniculi (n = 2). We also studied a four-year survey of an inter-laboratory quality control program including 9 centers that used this commercial assay. Sensitivity and specificity of the microsporidia generic assay were 86.4% and 93.3%, respectively. Encephalitozoon hellem and Encephalitozoon cuniculi were detected by the microsporidia generic PCR assay but not by the microsporidia typing PCR assay. These results were consistent with the results of the inter-laboratory quality control program. In conclusion, Bio-Evolution Real-time PCR assays are useful tools for intestinal microsporidiosis, but negative results for microsporidia typing assays require supplementary analyses to confirm E. hellem or E. cuniculi infections.

Cryptosporidiosis outbreaks linked to the public water supply in a military camp, France

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.

Cryptosporidiosis remains a neglected infectious disease, even in high-income countries. Most of the reported cases and outbreaks are related to drinking water and recreational water contaminated with Cryptosporidium spp. In Europe, the search for Cryptosporidium spp. and other parasites in stool or water samples is not routinely performed by laboratories, especially in the absence of dedicated national guidance on testing. In France, cryptosporidiosis is not a notifiable disease. In order to better assess the pathogens involved in foodborne and waterborne disease outbreaks a new outbreak investigation strategy was implemented in the French Armed Forces including: systematic stool sampling, routine syndromic multiplex PCR diagnoses, and pathogens genotyping. After several unexplained gastroenteritis outbreaks in a military camp in France, we identified the same C. hominis IbA10G2 isolate in the stools of patients and in the entire water distribution network. The highest levels of contamination were found in groundwater and in the water leaving the treatment plant. Our study demonstrates the value of syndromic diagnosis for gastroenteritis outbreaks investigation and highlights the importance of better assessing the microbiological risks associated with raw water.

Systemic efficacy on Cryptosporidium parvum infection of aminoxanide (RM-5061), a new amino-acid ester thiazolide prodrug of tizoxanide

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.

Detection of Infectious Cryptosporidium parvum Oocysts from Lamb's Lettuce: CC-qPCR's Intake

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.

Multicenter Evaluation of an ELISA for the Detection of Cryptosporidium spp. Antigen in Clinical Human Stool Samples

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.

Asymptomatic Cryptosporidium infections in ewes and lambs are a source of environmental contamination with zoonotic genotypes of Cryptosporidium parvum

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.

Evaluation of a modified method for the detection of Cryptosporidium oocysts on spinach leaves

Despite the infection risk associated with the consumption of contaminated food, techniques for recovering and detecting Cryptosporidium oocysts from fruit and vegetables are generally inadequate due to the variable recovery efficiencies and high reagent costs, such as those presented by ISO 18744:2016 "Microbiology of the food chain -Detection and enumeration of Cryptosporidium and Giardia in fresh leafy green vegetables and berry fruits". Although an improved method for recovering these parasites from Iceberg lettuce, which reported increased recovery efficiency as well as lower costs, has been published, it appears to have limitations for the recovery of Cryptosporidium from saponin-rich leaves such as spinach (Spinacia oleraceae), which have previously been implicated in Cryptosporidium parvum outbreaks. In this study, we refined the method to improve its use with these more challenging samples. The use of alkaline elution buffer (1 M glycine) of different pH values was evaluated for their effectiveness in removing C. parvum from spinach leaves. The refinement of Utaaker's method showed, from spinach leaves inoculated with 100 oocysts, an increased oocyst recovery rate with an overall mean recovery rate of 33.79% ± 2.82%. The emergence of parasitic foodborne illnesses and outbreaks associated with the consumption of fresh produce demonstrates the need for the development of an optimal recovery process for parasites from suspected foods. Results showed that refinement of existing protocols could improve the retrieval of Cryptosporidium oocysts from these more challenging leafy greens.

Survival and infectivity of Toxoplasma gondii and Cryptosporidium parvum oocysts bioaccumulated by Dreissena polymorpha

AIMS

The study was aimed to understand the depuration process of Cryptosporidium parvum and Toxoplasma gondii oocysts by zebra mussel (Dreissena polymorpha), to consider the use of the zebra mussel as a bioremediation tool.

MATERIALS AND METHODS

Two experiments were performed: (i) individual exposure of mussel to investigate oocyst transfers between bivalves and water and (ii) in vivo exposure to assess the ability of the zebra mussel to degrade oocysts.

RESULTS

(i) Our results highlighted a transfer of oocysts from the mussels to the water after 3 and 7 days of depuration; however, some oocysts were still bioaccumulated in mussel tissue. (ii) Between 7 days of exposure at 1000 or 10 000 oocysts/mussel/day and 7 days of depuration, the number of bioaccumulated oocysts did not vary but the number of infectious oocysts decreased.

CONCLUSION

Results show that D. polymorpha can release oocysts in water via (pseudo)faeces in depuration period. Oocysts remain bioaccumulated and infectious oocyst number decreases during the depuration period in zebra mussel tissues. Results suggest a degradation of bioaccumulated C. parvum and T. gondii oocysts.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study highlighted the potential use of D. polymorpha as a bioremediation tool to mitigate of protozoan contamination in water resources.

Update on Giardia: Highlights from the seventh International Giardia and Cryptosporidium Conference

Although Giardia duodenalis is recognized as one of the leading causes of parasitic human diarrhea in the world, knowledge of the mechanisms of infection is limited, as the pathophysiological consequences of infection remain incompletely elucidated. Similarly, the reason for and consequences of the very specific genome-organization in this parasite with 2 active nuclei is only partially known. Consistent with its tradition, the 7th International Giardia and Cryptosporidium Conference (IGCC 2019) was held from June 23 to 26, 2019, at the Faculty of Medicine and Pharmacy of the University of Rouen-Normandie, France, to discuss current research perspectives in the field. This renowned event brought together an international delegation of researchers to present and debate recent advances and identify the main research themes and knowledge gaps. The program for this interdisciplinary conference included all aspects of host-parasite relationships, from basic research to applications in human and veterinary medicine, as well as the environmental issues raised by water-borne parasites and their epidemiological consequences. With regard to Giardia and giardiasis, the main areas of research for which new findings and the most impressive communications were presented and discussed included: parasite ecology and epidemiology of giardiasis, Giardia-host interactions, and cell biology of Giardia, genomes and genomic evolution. The high-quality presentations discussed at the Conference noted breakthroughs and identified new opportunities that will inspire researchers and funding agencies to stimulate future research in a “one health” approach to improve basic knowledge and clinical and public health management of zoonotic giardiasis.

Corneal Pharmacokinetics of Voriconazole and Posaconazole following Intrastromal Injection and Posaconazole Eye Drops Instillation in Rats

Purpose/Aims: Infectious keratitis is a major cause of visual impairment and blindness worldwide. Common difficulties in treating fungal keratitis prompt new therapeutic possibilities. In this study, intrastromal voriconazole and posaconazole, and topical posaconazole were tested for their potential to obtain therapeutic cornea concentrations. Materials and Methods: Pharmacokinetics of triazole intracorneal/eye drop administration was studied in rats. Sixty-two rats were treated either by voriconazole or posaconazole. Twenty-nine and 33 rats received intrastromal injection of voriconazole solution (1 μl, 10 mg/ml) and posaconazole solution (1 μl, 18 mg/ml), respectively, administered under microscopic examination with a 32 gauge needle in the left cornea. Posaconazole (1.8% solution) eye drops were used. Cornea and plasma concentrations were determined using 2D HPLC separation and tandem MS, at 30 min, 3 h, 6 h, 24 h, 48 h, 72 h, and 144 h (6 days) post-intrastromal injection. The entire rat cornea was used for chromatography analyses. Results: In anesthetized rats, single intracorneal injection resulted, after 30 min, in respectively, >300 ng/mg and >260 ng/mg cornea concentrations, dropping to low levels within hours, while staying low in plasma. The effect of hourly posaconazole eye drops resulted in >10 ng/mg cornea concentration, which was maintained with instillations every 2 and then every 4 h. Conclusion: Our results show that there is little interest of intrastromal triazole administration due to the short duration of high cornea concentrations obtained after intracorneal injection. Posaconazole eye drops maintain therapeutic cornea concentrations in rats and could be used to treat severe infectious keratitis.

Cryptosporidiosis after treatment with fingolimod: a case report and pharmacovigilance review

Background

Cryptosporidium sp. are common intracellular parasites responsible of severe diarrhea in T-cell-immunocompromised patients. We report the first case of a woman who contracted cryptosporidiosis after treatment with fingolimod, a drug labeled for multiple sclerosis and responsible for marked lymphopenia.

Case presentation

A 60-year-old woman was admitted for abdominal pain diarrhea and fever. The patient suffered from multiple sclerosis and had been treated with fingolimod from august 2017 to september 2018 time of occurrence of the first digestive symptoms. Stool culture was negative but parasitological examination was positive for Cryptosporidium sp. Blood biological examination profound lymphopenia of 240/mm³ [17 CD4/mm³ (7%) and 32 CD8/mm³ (14%)]. Fingolimod was stopped, and the patient was put on nitazoxanide 500 mg bid for 7 days. The diarrhea resolved and no relapse was observed. Six other cases were found in the Pharmacovigilance database.

Conclusion

Physicians should be aware of this association and screen for Cryptosporidium in cases of diarrhea in patients treated with fingolimod. Patients should be aware of this risk and advise to take appropriate measures to avoid such contamination.

Update on Cryptosporidium spp.: highlights from the Seventh International Giardia and Cryptosporidium Conference

While cryptosporidiosis is recognized as being among the most common causes of human parasitic diarrhea in the world, there is currently limited knowledge on Cryptosporidium infection mechanisms, incomplete codification of diagnostic methods, and a need for additional therapeutic options. In response, the Seventh International Giardia and Cryptosporidium Conference (IGCC 2019) was hosted from 23 to 26 June 2019, at the Rouen Normandy University, France. This trusted event brought together an international delegation of researchers to synthesize recent advances and identify key research questions and knowledge gaps. The program of the interdisciplinary conference included all aspects of host-parasite relationships from basic research to applications to human and veterinary medicine, and environmental issues associated with waterborne parasites and their epidemiological consequences. In relation to Cryptosporidium and cryptosporidiosis, the primary research areas for which novel findings and the most impressive communications were presented and discussed included: Cryptosporidium in environmental waters, seafood, and fresh produce; Animal epidemiology; Human cryptosporidiosis and epidemiology; Genomes and genomic evolution encompassing: Comparative genomics of Cryptosporidium spp., Genomic insights into biology, Acquiring and utilizing genome sequences, Genetic manipulation; Host-parasite interaction (immunology, microbiome); and Diagnosis and treatment. High quality presentations discussed at the conference reflected decisive progress and identified new opportunities that will engage investigators and funding agencies to spur future research in a “one health” approach to improve basic knowledge and the clinical and public health management of zoonotic cryptosporidiosis.

Developing collaborative works for faster progress on fungal respiratory infections in cystic fibrosis

Cystic fibrosis (CF) is the major genetic inherited disease in Caucasian populations. The respiratory tract of CF patients displays a sticky viscous mucus, which allows for the entrapment of airborne bacteria and fungal spores and provides a suitable environment for growth of microorganisms, including numerous yeast and filamentous fungal species. As a consequence, respiratory infections are the major cause of morbidity and mortality in this clinical context. Although bacteria remain the most common agents of these infections, fungal respiratory infections have emerged as an important cause of disease. Therefore, the International Society for Human and Animal Mycology (ISHAM) has launched a working group on Fungal respiratory infections in Cystic Fibrosis (Fri-CF) in October 2006, which was subsequently approved by the European Confederation of Medical Mycology (ECMM). Meetings of this working group, comprising both clinicians and mycologists involved in the follow-up of CF patients, as well as basic scientists interested in the fungal species involved, provided the opportunity to initiate collaborative works aimed to improve our knowledge on these infections to assist clinicians in patient management. The current review highlights the outcomes of some of these collaborative works in clinical surveillance, pathogenesis and treatment, giving special emphasis to standardization of culture procedures, improvement of species identification methods including the development of nonculture-based diagnostic methods, microbiome studies and identification of new biological markers, and the description of genotyping studies aiming to differentiate transient carriage and chronic colonization of the airways. The review also reports on the breakthrough in sequencing the genomes of the main Scedosporium species as basis for a better understanding of the pathogenic mechanisms of these fungi, and discusses treatment options of infections caused by multidrug resistant microorganisms, such as Scedosporium and Lomentospora species and members of the Rasamsonia argillacea species complex.

Cryptosporidiosis Outbreak in Immunocompetent Children from a Remote Area of French Guiana

In September 2014, an increase in the number of Cryptosporidium spp. gastrointestinal tract infections was reported over a 6-month period among children living in a remote area along the Maroni River in French Guiana. Children presented gastroenteritis symptoms with Cryptosporidium-positive stools. Questionnaires were administered and stool examinations were controlled 3 months after the onset of symptoms. Data collection included demographics, food consumption, river behavior, symptoms, and outcome. Stool specimens were tested using microscopy and polymerase chain reaction. Samples from the water systems were examined for turbidity and culture for bacteria. Data from the reference laboratory were analyzed to calculate the median cryptosporidiosis incidence among immunocompetent patients from 2008 to 2015. Data on gastroenteritis cases reported by the Delocalized Center for Prevention and Care in the area were also collected. We report a cluster of 14 cases. All cases were children, aged between 4.5 and 38 months. Seven reported moderate to severe dehydration and required hospitalization. Speciation and microbiological typing revealed the cluster strain was Cryptosporidium hominis subtype IbA10G2 but C. hominis IbA9G2 and IbA15G1 strains were also identified. The median incidence in French Guiana was 5.8 cases per year before the outbreak. The first cases of the cluster appeared in the dry season. We describe the clinical features, epidemiology, and state of current investigations for the largest documented outbreak of cryptosporidiosis in French Guiana.

Assessing viability and infectivity of foodborne and waterborne stages (cysts/oocysts) of Giardia duodenalis, Cryptosporidium spp., and Toxoplasma gondii: a review of methods

Giardia duodenalis, Cryptosporidium spp. and Toxoplasma gondii are protozoan parasites that have been highlighted as emerging foodborne pathogens by the Food and Agriculture Organization of the United Nations and the World Health Organization. According to the European Food Safety Authority, 4786 foodborne and waterborne outbreaks were reported in Europe in 2016, of which 0.4% were attributed to parasites including Cryptosporidium, Giardia and Trichinella. Until 2016, no standardized methods were available to detect Giardia, Cryptosporidium and Toxoplasma (oo)cysts in food. Therefore, no regulation exists regarding these biohazards. Nevertheless, considering their low infective dose, ingestion of foodstuffs contaminated by low quantities of these three parasites can lead to human infection. To evaluate the risk of protozoan parasites in food, efforts must be made towards exposure assessment to estimate the contamination along the food chain, from raw products to consumers. This requires determining: (i) the occurrence of infective protozoan (oo)cysts in foods, and (ii) the efficacy of control measures to eliminate this contamination. In order to conduct such assessments, methods for identification of viable (i.e. live) and infective parasites are required. This review describes the methods currently available to evaluate infectivity and viability of G. duodenalis cysts, Cryptosporidium spp. and T. gondii oocysts, and their potential for application in exposure assessment to determine the presence of the infective protozoa and/or to characterize the efficacy of control measures. Advantages and limits of each method are highlighted and an analytical strategy is proposed to assess exposure to these protozoa.

Common occurrence of Cryptosporidium hominis in asymptomatic and symptomatic calves in France

BACKGROUND

Cryptosporidium spp. infections are the most frequent parasitic cause of diarrhea in humans and cattle. However, asymptomatic cases are less often documented than symptomatic cases or cases with experimentally infected animals. Cryptosporidium (C.) hominis infection accounts for the majority of pediatric cases in several countries, while C. parvum is a major cause of diarrhea in neonatal calves. In cattle Cryptosporidium spp. infection can be caused by C. parvum, C. bovis, C.andersoni and C. ryanae, and recently, reports of cattle cases of C. hominis cryptosporidiosis cases suggest that the presence of C. hominis in calves was previously underestimated.

METHODOLOGY/PRINCIPAL FINDINGS

From February to November 2015, Cryptosporidium spp. infected calves were detected in 29/44 randomly included farms from 5 geographic regions of France. C. hominis and C. parvum were found in 12/44 and 26/44 farms, respectively with higher C. hominis prevalence in the western region. In 9 farms, both C. parvum and C. hominis were detected. Eighty-six of 412 (73/342 asymptomatic and 13/70 symptomatic) one to nine-week-old calves shed C. hominis or C. parvum oocysts (15 and 71 calves, respectively), with no mixed infection detected. The predominant C. hominis IbA9G3 genotype was present in all regions, and more frequent in the western region. An incompletely characterized Ib, and the IbA13G3, IbA9G2 and IbA14G2 genotypes were present only in the western region. For C. parvum, the most frequent genotype was IIaA16G3R1 with no geographic clustering. Most C. hominis infected calves were asymptomatic, with some exceptions of IbA9G2 and IbA9G3 isolates, while C. parvum IIaA16G3R1 was associated with symptoms.

CONCLUSIONS/SIGNIFICANCE

Present results indicate for the first time that in several geographic regions of France, C. hominis was present in about one fifth of both asymptomatic and symptomatic infected calves, with isolated genotypes likely associated with human infection. Further investigations are aimed at documenting direct or indirect transmissions between livestock and humans.

Ruling out nosocomial transmission of Cryptosporidium in a renal transplantation unit: case report

Background

Cryptosporidium spp. is a ubiquitous parasite affecting humans as well as domestic and wild vertebrates, causing diarrhea in both immunocompetent and immunocompromised hosts worldwide. Its transmission occurs primarily by the fecal-oral route. In humans, C. parvum and C. hominis are the most prevalent species, whereas immunocompetent and immunocompromised individuals can also be infected by other zoonotic species. Renal transplant patients are prone to develop cryptosporidiosis, which can induce severe and life-threatening diarrhea.

Case presentation

We report here a series of nearly concomitant cases of acute symptomatic cryptosporidiosis in three renal transplant patients attending the Strasbourg University Hospital Nephrology Unit. The clinical presentation was persistent diarrhea and acute renal failure. The diagnosis was confirmed by microscopic stool examination using a modified Ziehl-Neelsen staining method and species identification by molecular tools. All patients were treated with nitazoxanide and recovered from diarrhea after 14 days of therapy.

Conclusion

Genotypic species identification was not consistent with an epidemic context, thus underlining the need for genotyping to monitor at risk patients.

Prevalence and Risk Factors for Intestinal Protozoan Infections with Cryptosporidium, Giardia, Blastocystis and Dientamoeba among Schoolchildren in Tripoli, Lebanon

BACKGROUND

Intestinal protozoan infections are confirmed as major causes of diarrhea, particularly in children, and represent a significant, but often neglected, threat to public health. No recent data were available in Lebanon concerning the molecular epidemiology of protozoan infections in children, a vulnerable population at high risk of infection.

METHODOLOGY AND PRINCIPAL FINDINGS

In order to improve our understanding of the epidemiology of intestinal pathogenic protozoa, a cross-sectional study was conducted in a general pediatric population including both symptomatic and asymptomatic subjects. After obtaining informed consent from the parents or legal guardians, stool samples were collected in January 2013 from 249 children in 2 schools in Tripoli, Lebanon. Information obtained from a standard questionnaire included demographic characteristics, current symptoms, socioeconomic status, source of drinking water, and personal hygiene habits. After fecal examination by both microscopy and molecular tools, the overall prevalence of parasitic infections was recorded as 85%. Blastocystis spp. presented the highest infection rate (63%), followed by Dientamoeba fragilis (60.6%), Giardia duodenalis (28.5%) and Cryptosporidium spp. (10.4%). PCR was also performed to identify species and genotypes of Cryptosporidium, subtypes of Blastocystis, and assemblages of Giardia. Statistical analysis using a logistic regression model showed that contact with family members presenting gastrointestinal disorders was the primary risk factor for transmission of these protozoa.

CONCLUSIONS

This is the first study performed in Lebanon reporting the prevalence and the clinical and molecular epidemiological data associated with intestinal protozoan infections among schoolchildren in Tripoli. A high prevalence of protozoan parasites was found, with Blastocystis spp. being the most predominant protozoans. Although only 50% of children reported digestive symptoms, asymptomatic infection was observed, and these children may act as unidentified carriers. This survey provides necessary information for designing prevention and control strategies to reduce the burden of these protozoan infections, especially in children.

Pilot-Scale Pulsed UV Light Irradiation of Experimentally Infected Raspberries Suppresses Cryptosporidium parvum Infectivity in Immunocompetent Suckling Mice

Cryptosporidium spp., a significant cause of foodborne infection, have been shown to be resistant to most chemical food disinfectant agents and infective for weeks in irrigation waters and stored fresh vegetal produce. Pulsed UV light (PL) has the potential to inactivate Cryptosporidium spp. on surfaces of raw or minimally processed foods or both. The present study aimed to evaluate the efficacy of PL on viability and in vivo infectivity of Cryptosporidium parvum oocysts present on raspberries, a known source of transmission to humans of oocyst-forming apicomplexan pathogens. The skin of each of 20 raspberries was experimentally inoculated with five 10-μl spots of an oocyst suspension containing 6 × 10(7) oocysts per ml (Nouzilly isolate). Raspberries were irradiated by PL flashes (4 J/cm(2) of total fluence). This dose did not affect colorimetric or organoleptic characteristics of fruits. After immunomagnetic separation from raspberries, oocysts were bleached and administered orally to neonatal suckling mice. Seven days after infection, mice were euthanized, and the number of oocysts in the entire small intestine was individually assessed by immunofluorescence flow cytometry. Three of 12 and 12 of 12 inoculated mice that received 10 and 100 oocysts isolated from nonirradiated raspberries, respectively, were found infected. Four of 12 and 2 of 12 inoculated mice that received 10(3) and 10(4) oocysts from irradiated raspberries, respectively, were found infected. Oocyst counts were lower in animals inoculated with 10(3) and 10(4) oocysts from irradiated raspberries (92 ± 144 and 38 ± 82, respectively) than in animals infected with 100 oocysts from nonirradiated raspberries (35,785 ± 66,221, P = 0.008). PL irradiation achieved oocyst reductions of 2 and 3 log for an inoculum of 10(3) and 10(4) oocysts, respectively. The present pilot-scale evaluation suggests that PL is an effective mode of decontamination for raspberries and prompts further applicability studies in industrial contexts.

Assessment of microscopic and molecular tools for the diagnosis and follow-up of cryptosporidiosis in patients at risk

Cryptosporidiosis is an important though underreported public health concern. Molecular tools might be helpful in improving its diagnosis. In this study, ZR Fecal DNA MiniPrep™ Kit (ZR) and NucliSens® easyMAG® (EM) were compared using four Cryptosporidium-seeded feces and 29 Cryptosporidium-positive stools. Thereafter, ZR was selected for prospective evaluation of Cryptosporidium detection by 18S rDNA and LAXER quantitative PCR (qPCR) in 69 stools from 56 patients after Cryptosporidium detection by glycerin, modified Ziehl-Neelsen (ZN) and auramine-phenol (AP) stainings. The combination of any of the two extraction methods with 18S qPCR yielded adequate detection of Cryptosporidium in seeded stools, but the ZR kit showed the best performance. All 29 Cryptosporidium-positive samples were positive with 18S qPCR, after both ZR and EM extraction. However, false-negative results were found with LAXER qPCR or nested PCR. Cryptosporidiosis was diagnosed in 7/56 patients. All the microscopic methods enabled the initial diagnosis, but Cryptosporidium was detected in 12, 13, and 14 samples from these seven patients after glycerin, ZN, and AP staining respectively. Among these samples, 14 and 12 were positive with 18S and LAXER qPCR respectively. In two patients, Cryptosporidium DNA loads were found to be correlated with clinical evolution. Although little known, glycerin is a sensitive method for the initial detection of Cryptosporidium. When combined with 18S qPCR, ZR extraction, which had not been evaluated so far for Cryptosporidium, was an accurate tool for detecting Cryptosporidium and estimating the oocyst shedding in the course of infection.

Semi-automated repetitive sequence-based PCR amplification for species of the Scedosporium apiospermum complex

PURPOSE

The Scedosporium apiospermum species complex usually ranks second among the filamentous fungi colonizing the airways of patients with cystic fibrosis (CF), but little is known about the molecular epidemiology of the airway colonization.

METHODS

Polymerase chain reaction (PCR) amplification of repetitive sequences (rep-PCR) was applied to the retrospective analysis of a panel of isolates already studied by random amplification of polymorphic DNA (RAPD) and comprising 63 isolates recovered from sputa from 9 CF patients. Results were compared to those obtained previously by RAPD, and herein by beta-tubulin (TUB) gene sequencing and Multilocus Sequence Typing (MLST).

RESULTS

Within the panel of isolates studied,S. apiospermum sensu stricto and Scedosporium boydii, as expected, were the predominant species with 21 and 36 isolates, respectively. Four isolates from one patient were identified as Scedosporium aurantiacum, whereas two isolates belonged to the Pseudallescheria ellipsoidea subgroup of S. boydii rep-PCR analysis of these isolates clearly differentiated the three species and P. ellipsoidea isolates, whatever the rep-PCR kit used, and also permitted strain differentiation. When using the mold primer kit, results from rep-PCR were in close agreement with those obtained by MLST. For both S. apiospermum and S. boydii, 8 genotypes were differentiated by rep-PCR and MLST compared to 10 by RAPD. All S. aurantiacum isolates shared the same RAPD genotype and exhibited the same rep-PCR profile and sequence type.

CONCLUSIONS

These results illustrate the efficacy of rep-PCR for both species identification within the S. apiospermum complex and genotyping for the two major species of this complex.Abstract presentation: Part of this work was presented during the 18th Congress of the International Society for Human and Animal Mycology, Berlin (Germany), June 2012.S. Giraud, C. Godon, A. Rougeron, J.P. Bouchara and L. Favennec are members of the ECMM/ISHAM working group on Fungal respiratory infections in Cystic Fibrosis(Fri-CF).

Rasamsonia argillacea species complex: taxonomy, pathogenesis and clinical relevance

Since 2010, colonizations/infections by Rasamsonia argillacea species complex, previously known as Geosmithia argillacea, have been regularly reported in literature. We reviewed all available cases focusing on pathogenesis and clinical relevance. The number of cases may be underestimated, as these fungi are frequently misidentified as Penicillium or Paecilomyces species. Major underlying conditions that predispose for infections by the R. argillacea species complex include cystic fibrosis (CF) and chronic granulomatous disease (CGD). While the pathogenic role of the colonization of CF lungs is still under debate, these molds are the causative agent of pneumonia and/or invasive infections in CGD patients. Given their thermotolerance and their resistance to various antifungals, especially the azole drugs, a special attention should be paid to the chronic colonization of the airways by these fungi in CF and CGD patients.

Protozoa interaction with aquatic invertebrate: interest for watercourses biomonitoring

Toxoplasma gondii, Cryptosporidium parvum, and Giardia duodenalis are human waterborne protozoa. These worldwide parasites had been detected in various watercourses as recreational, surface, drinking, river, and seawater. As of today, water protozoa detection was based on large water filtration and on sample concentration. Another tool like aquatic invertebrate parasitism could be used for sanitary and environmental biomonitoring. In fact, organisms like filter feeders could already filtrate and concentrate protozoa directly in their tissues in proportion to ambient concentration. So molluscan shellfish can be used as a bioindicator of protozoa contamination level in a site since they were sedentary. Nevertheless, only a few researches had focused on nonspecific parasitism like protozoa infection on aquatic invertebrates. Objectives of this review are twofold: Firstly, an overview of protozoa in worldwide water was presented. Secondly, current knowledge of protozoa parasitism on aquatic invertebrates was detailed and the lack of data of their biological impact was pointed out.

Clinical and microbiological efficacy of micafungin on Geosmithia argillacea infection in a cystic fibrosis patient

Cystic fibrosis (CF) patients are at high risk of colonization of the airways by a number of fungi, including the emerging opportunistic fungus Geosmithia argillacea. We report the eradication of respiratory G. argillacea associated with clinical resolution of severe symptoms by high-dose and prolonged micafungin therapy in a young CF patient.

Effects of octreotide on jejunal hypersensitivity triggered by Cryptosporidium parvum intestinal infection in an immunocompetent suckling rat model

BACKGROUND

Similar to other bacterial or protozoan infections, human cryptosporidiosis may trigger postinfectious irritable bowel syndrome (IBS)-like symptoms, a condition in which enhanced visceral perception of pain during intestinal distension plays a pivotal role. In an immunocompetent suckling rat model which mimicks features of postinfectious IBS, Cryptosporidium parvum infection induces long-lasting jejunal hypersensitivity to distension in association with intestinal activated mast cell accumulation. The aim of the present study was to explore in this model whether octreotide, a somatostatin agonist analog, could prevent the development of jejunal hypersensitivity and intestinal mast cell/nerve fiber accumulation.

METHODS

Five-day-old Sprague-Dawley rats were infected with C. parvum and treated 10 days later with octreotide (50 g kg(-1) day(-1), i.p.) for 7 days.

KEY RESULTS

Compared with untreated infected rats, octreotide treatment of infected rats resulted in increased weight gain [day 23 postinfection (PI)], decreased food intake (day 16 PI), and a reduction in jejunal villus alterations (day 14 PI), CD3(+) IEL (day 37 PI) and mast cell (days 37 and 50 PI) accumulations, nerve fiber densities (day 50 PI), and hypersensitivity to distension (day 120 PI). In uninfected rats, the effects of octreotide treatment were limited to higher weight gain (days 16 and 23 PI) and decreased food intake (day 23 PI) compared with uninfected-untreated rats.

CONCLUSIONS & INFERENCES

Data confirms the relevance of the present rat model to postinfectious IBS studies and prompt further investigation of somatostatin-dependent regulatory interactions in cryptosporidiosis.

Intensive exploitation of a karst aquifer leads to Cryptosporidium water supply contamination

Groundwater from karst aquifers is an important source of drinking water worldwide. Outbreaks of cryptosporidiosis linked to surface water and treated public water are regularly reported. Cryptosporidium oocysts are resistant to conventional drinking water disinfectants and are a major concern for the water industry. Here, we examined conditions associated with oocyst transport along a karstic hydrosystem, and the impact of intensive exploitation on Cryptosporidium oocyst contamination of the water supply. We studied a well-characterized karstic hydrosystem composed of a sinkhole, a spring and a wellbore. Thirty-six surface water and groundwater samples were analyzed for suspended particulate matter, turbidity, electrical conductivity, and Cryptosporidium and Giardia (oo)cyst concentrations. (Oo)cysts were identified and counted by means of solid-phase cytometry (ChemScan RDI(®)), a highly sensitive method. Cryptosporidium oocysts were detected in 78% of both surface water and groundwater samples, while Giardia cysts were found in respectively 22% and 8% of surface water and groundwater samples. Mean Cryptosporidium oocyst concentrations were 29, 13 and 4/100 L at the sinkhole, spring and wellbore, respectively. Cryptosporidium oocysts were transported from the sinkhole to the spring and the wellbore, with respective release rates of 45% and 14%, suggesting that oocysts are subject to storage and remobilization in karst conduits. Principal components analysis showed that Cryptosporidium oocyst concentrations depended on variations in hydrological forcing factors. All water samples collected during intensive exploitation contained oocysts. Control of Cryptosporidium oocyst contamination during intensive exploitation is therefore necessary to ensure drinking water quality.

Ultra low κ PECVD Porogen Approach: Matrix Precursors Comparison and Porogen Removal Treatment Study

The introduction of new dielectrics into silicon chip interconnection technology is necessary to increase electrical performance. Sub-65nm technologies need κ values below 2.5 and the main way to reduce the dielectric constant is to introduce porosity. This work reports results concerning a two steps PECVD porogen approach to perform Ultra Low κ (κ <2.5). The first step is an hybrid material deposition: i.e. an a-SiOC:H matrix containing organic sacrificial inclusions (porogen phase). In the second step, the porogen is removed by a suitable curing to generate porosity. Two siloxane precursors (decamethylcyclopentasiloxane and diethoxymethylsilane) were evaluated as matrix precursors. Their influences, as well as O2 addition in plasma gas feed, in terms of cross-linking and incorporation were evaluated by FTIR analysis. Thermal anneal and UV treatment (thermally assisted) were evaluated as a curing second step. It allows to better understand this critical step which combines porogen removal and material cross-linking. By optimizing deposition and curing parameters, κ value lower than 2.4 were obtained.

Geosmithia argillacea: an emerging pathogen in patients with cystic fibrosis

We report eight cases of airway colonization by Geosmithia argillacea in patients with cystic fibrosis. This filamentous fungus, resembling members of the genera Penicillium and Paecilomyces, was identified by molecular analysis. All patients carried a mutation on each CFTR (cystic fibrosis transmembrane conductance regulator) allele, with at least one copy of the F508del mutation. The first isolation of this fungus occurred from F508del-homozygous patients at a younger age than in F508del-heterozygous patients. Before recovery of G. argillacea, all patients were treated with itraconazole; two of them had also received voriconazole for an Aspergillus fumigatus infection. However, antifungal susceptibility patterns showed high MICs of voriconazole for all isolates, and high MICs of amphotericin B and itraconazole for the majority of them, but mostly low minimum effective concentrations (MECs) of caspofungin. The appearance and persistence of G. argillacea in the airways were not associated with exacerbation of the disease. However, the clinical implications of G. argillacea, particularly in immunocompromised patients, remain a concern, particularly given recent observations suggesting that this fungus may also cause disseminated infections.

Evaluation of water treatment plant UV reactor efficiency against Cryptosporidium parvum oocyst infectivity in immunocompetent suckling mice

AIM

To assess the efficiency of a medium-pressure UV reactor under full-scale water treatment plant (WTP) conditions on the infectivity of Cryptosporidium parvum oocysts in an Naval Medical Research Institute (NMRI) suckling mice infectivity model.

METHODS AND RESULTS

Six/seven-day-old mice were administered orally 2-10x10(4)Cryptosporidium parvum oocysts. Compared with nonirradiated oocysts, 40 mJ cm(-2) UV irradiation of ingested oocysts resulted 7 days later in a 3.4-4.0 log10 reduction in the counts of small intestine oocysts, using a fluorescent flow cytometry assay.

CONCLUSION

Present data extend to industrial conditions previous observations of the efficiency of UV irradiation against Cryptosporidium parvum oocyst in vivo development.

SIGNIFICANCE AND IMPACT OF THE STUDY

Present results suggest that in WTP conditions, a medium-pressure UV reactor is efficient in reducing the infectivity of Cryptosporidium parvum oocysts, one of the most resistant micro-organisms present in environmental waters.

In vitro efficacy of nitro- and halogeno-thiazolide/thiadiazolide derivatives against Sarcocystis neurona

Sarcocystis neurona is an obligate intracellular parasite that causes equine protozoal myeloencephalitis (EPM). The aim of this work was to document inhibitory activities of nitazoxanide (NTZ, [2-acetolyloxy-N-(5-nitro 2-thiazolyl) benzamide]) and new thiazolides/thiadiazolides on S. neurona in vitro development, and investigate their structure-activity relationships. S. neurona was grown in bovine turbinate cell cultures. At concentrations varying from 1.0 to 5.0mg/L, nitazoxanide and 21 of 32 second generation thiazolide/thiadiazolide agents exerted a > or =95% maximum inhibition on S. neurona development. Most active agents were either NO(2) or halogen substituted in position 5 of their thiazole moiety. In contrast, other 5-substitutions such as hydrogen, methyl, SO(2)CH(3), and CH(3) negatively impacted activity. Compared with derivatives with an acetylated benzene moiety, deacetylated compounds which most probably represent primary metabolites exhibited similar inhibitory activities. Present data provide the first evidence of in vitro inhibitory activities of nitazoxanide and new thiazolides/thiadiazolides on S. neurona development. Active halogeno-thiazolide/thiadiazolides may provide a valuable nitro-free alternative to nitazoxanide for EPM treatment depending on further evaluation of their in vivo activities.