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Featured researches published by Arnaud Fontanet.


The Lancet | 2016

Guillain-Barré Syndrome outbreak associated with Zika virus infection in French Polynesia: a case-control study

Van-Mai Cao-Lormeau; Alexandre Blake; Sandrine Mons; Stéphane Lastère; Claudine Roche; Jessica Vanhomwegen; Timothée Dub; Laure Baudouin; Anita Teissier; Philippe Larre; Anne-Laure Vial; Christophe Decam; Valérie Choumet; Susan K. Halstead; Hugh J. Willison; L. Musset; Jean-Claude Manuguerra; Philippe Desprès; Emmanuel Fournier; Henri-Pierre Mallet; Didier Musso; Arnaud Fontanet; Jean Neil; Frédéric Ghawché

BACKGROUND Between October, 2013, and April, 2014, French Polynesia experienced the largest Zika virus outbreak ever described at that time. During the same period, an increase in Guillain-Barré syndrome was reported, suggesting a possible association between Zika virus and Guillain-Barré syndrome. We aimed to assess the role of Zika virus and dengue virus infection in developing Guillain-Barré syndrome. METHODS In this case-control study, cases were patients with Guillain-Barré syndrome diagnosed at the Centre Hospitalier de Polynésie Française (Papeete, Tahiti, French Polynesia) during the outbreak period. Controls were age-matched, sex-matched, and residence-matched patients who presented at the hospital with a non-febrile illness (control group 1; n=98) and age-matched patients with acute Zika virus disease and no neurological symptoms (control group 2; n=70). Virological investigations included RT-PCR for Zika virus, and both microsphere immunofluorescent and seroneutralisation assays for Zika virus and dengue virus. Anti-glycolipid reactivity was studied in patients with Guillain-Barré syndrome using both ELISA and combinatorial microarrays. FINDINGS 42 patients were diagnosed with Guillain-Barré syndrome during the study period. 41 (98%) patients with Guillain-Barré syndrome had anti-Zika virus IgM or IgG, and all (100%) had neutralising antibodies against Zika virus compared with 54 (56%) of 98 in control group 1 (p<0.0001). 39 (93%) patients with Guillain-Barré syndrome had Zika virus IgM and 37 (88%) had experienced a transient illness in a median of 6 days (IQR 4-10) before the onset of neurological symptoms, suggesting recent Zika virus infection. Patients with Guillain-Barré syndrome had electrophysiological findings compatible with acute motor axonal neuropathy (AMAN) type, and had rapid evolution of disease (median duration of the installation and plateau phases was 6 [IQR 4-9] and 4 days [3-10], respectively). 12 (29%) patients required respiratory assistance. No patients died. Anti-glycolipid antibody activity was found in 13 (31%) patients, and notably against GA1 in eight (19%) patients, by ELISA and 19 (46%) of 41 by glycoarray at admission. The typical AMAN-associated anti-ganglioside antibodies were rarely present. Past dengue virus history did not differ significantly between patients with Guillain-Barré syndrome and those in the two control groups (95%, 89%, and 83%, respectively). INTERPRETATION This is the first study providing evidence for Zika virus infection causing Guillain-Barré syndrome. Because Zika virus is spreading rapidly across the Americas, at risk countries need to prepare for adequate intensive care beds capacity to manage patients with Guillain-Barré syndrome. FUNDING Labex Integrative Biology of Emerging Infectious Diseases, EU 7th framework program PREDEMICS. and Wellcome Trust.


The Lancet | 2016

Association between Zika virus and microcephaly in French Polynesia, 2013–15: a retrospective study

Simon Cauchemez; Marianne Besnard; Priscillia Bompard; Timothée Dub; Prisca Guillemette-Artur; Dominique Eyrolle-Guignot; Henrik Salje; Maria D. Van Kerkhove; Véronique Abadie; Catherine Garel; Arnaud Fontanet; Henri-Pierre Mallet

BACKGROUND The emergence of Zika virus in the Americas has coincided with increased reports of babies born with microcephaly. On Feb 1, 2016, WHO declared the suspected link between Zika virus and microcephaly to be a Public Health Emergency of International Concern. This association, however, has not been precisely quantified. METHODS We retrospectively analysed data from a Zika virus outbreak in French Polynesia, which was the largest documented outbreak before that in the Americas. We used serological and surveillance data to estimate the probability of infection with Zika virus for each week of the epidemic and searched medical records to identify all cases of microcephaly from September, 2013, to July, 2015. Simple models were used to assess periods of risk in pregnancy when Zika virus might increase the risk of microcephaly and estimate the associated risk. FINDINGS The Zika virus outbreak began in October, 2013, and ended in April, 2014, and 66% (95% CI 62-70) of the general population were infected. Of the eight microcephaly cases identified during the 23-month study period, seven (88%) occurred in the 4-month period March 1 to July 10, 2014. The timing of these cases was best explained by a period of risk in the first trimester of pregnancy. In this model, the baseline prevalence of microcephaly was two cases (95% CI 0-8) per 10,000 neonates, and the risk of microcephaly associated with Zika virus infection was 95 cases (34-191) per 10,000 women infected in the first trimester. We could not rule out an increased risk of microcephaly from infection in other trimesters, but models that excluded the first trimester were not supported by the data. INTERPRETATION Our findings provide a quantitative estimate of the risk of microcephaly in fetuses and neonates whose mothers are infected with Zika virus. FUNDING Labex-IBEID, NIH-MIDAS, AXA Research fund, EU-PREDEMICS.


AIDS | 2005

Incidence and risk factors of immune reconstitution inflammatory syndrome complicating HIV-associated cryptococcosis in France.

Olivier Lortholary; Arnaud Fontanet; Nathalie Memain; Antoine Martin; Karine Sitbon; Françoise Dromer

Background:Immune reconstitution inflammatory syndrome (IRIS) in association with cryptococcosis has been anecdotically reported following administration of highly active antiretroviral therapy (HAART). Objective:To analyse the incidence and risk factors for IRIS-associated cryptococcosis among HIV-infected patients. Design:Retrospective multicentre study between 1996 and 2000 through the French Cryptococcosis Database. Methods:Subsequent occurrence of IRIS examined in 120 HIV-infected adult patients treated with HAART and experiencing a first episode of culture-confirmed cryptococcosis. Results:Ten patients developed IRIS during the study period, giving an incidence of 10/239, or 4.2/100 person-years [95% confidence interval (CI), 2.2–7.8]. IRIS consisted of acute symptoms consistent with inflammation occurring within a median of 8 months (range, 2–37) after the diagnosis of cryptococcosis in the context of negative cultures and immunological and/or virological response to HAART. Radiology and histopathology detected features compatible with inflammation. Symptom severity required transfer into intensive care units for three patients and use of anti-inflammatory drugs for four. Three patients with evolutive IRIS died. Compared with patients without IRIS for whom complete clinical and microbiological information were available at baseline, previously unknown HIV infection [odds ratio (OR), 4.8; 95% CI, 1.0–21.7], CD4 cell count < 7 × 106 cells/l (OR, 4.0; 95% CI, 0.9–17.2), fungaemia (OR, 6.1; 95% CI, 1.1–35.2) and HAART initiation within 2 months of cryptococcosis diagnosis (OR, 5.50; 95% CI, 1.0–29.6) were independently associated with the risk of subsequent IRIS. Conclusions:IRIS-related cryptococcosis was observed more frequently in severely immunocompromised patients with disseminated infection and HAART initiation soon after the diagnosis.


The Lancet | 2013

Clinical features and viral diagnosis of two cases of infection with Middle East Respiratory Syndrome coronavirus: a report of nosocomial transmission

Benoit Guery; Julien Poissy; Loubna El Mansouf; Caroline Séjourné; Nicolas Ettahar; Xavier Lemaire; Fanny Vuotto; Sylvie Behillil; Vincent Enouf; Valérie Caro; A. Mailles; Didier Che; Jean-Claude Manuguerra; Daniel Mathieu; Arnaud Fontanet; Sylvie van der Werf

Summary Background Human infection with a novel coronavirus named Middle East Respiratory Syndrome coronavirus (MERS-CoV) was first identified in Saudi Arabia and the Middle East in September, 2012, with 44 laboratory-confirmed cases as of May 23, 2013. We report detailed clinical and virological data for two related cases of MERS-CoV disease, after nosocomial transmission of the virus from one patient to another in a French hospital. Methods Patient 1 visited Dubai in April, 2013; patient 2 lives in France and did not travel abroad. Both patients had underlying immunosuppressive disorders. We tested specimens from the upper (nasopharyngeal swabs) or the lower (bronchoalveolar lavage, sputum) respiratory tract and whole blood, plasma, and serum specimens for MERS-CoV by real-time RT-PCR targeting the upE and Orf1A genes of MERS-CoV. Findings Initial clinical presentation included fever, chills, and myalgia in both patients, and for patient 1, diarrhoea. Respiratory symptoms rapidly became predominant with acute respiratory failure leading to mechanical ventilation and extracorporeal membrane oxygenation (ECMO). Both patients developed acute renal failure. MERS-CoV was detected in lower respiratory tract specimens with high viral load (eg, cycle threshold [Ct] values of 22·9 for upE and 24 for Orf1a for a bronchoalveolar lavage sample from patient 1; Ct values of 22·5 for upE and 23·9 for Orf1a for an induced sputum sample from patient 2), whereas nasopharyngeal specimens were weakly positive or inconclusive. The two patients shared the same room for 3 days. The incubation period was estimated at 9–12 days for the second case. No secondary transmission was documented in hospital staff despite the absence of specific protective measures before the diagnosis of MERS-CoV was suspected. Patient 1 died on May 28, due to refractory multiple organ failure. Interpretation Patients with respiratory symptoms returning from the Middle East or exposed to a confirmed case should be isolated and investigated for MERS-CoV with lower respiratory tract sample analysis and an assumed incubation period of 12 days. Immunosuppression should also be taken into account as a risk factor. Funding French Institute for Public Health Surveillance, ANR grant Labex Integrative Biology of Emerging Infectious Diseases, and the European Communitys Seventh Framework Programme projects EMPERIE and PREDEMICS.


The Lancet | 2013

Interhuman transmissibility of Middle East respiratory syndrome coronavirus: estimation of pandemic risk.

Romulus Breban; Julien Riou; Arnaud Fontanet

Summary Background The new Middle East respiratory syndrome coronavirus (MERS-CoV) infection shares many clinical, epidemiological, and virological similarities with that of severe acute respiratory syndrome (SARS)-CoV. We aimed to estimate virus transmissibility and the epidemic potential of MERS-CoV, and to compare the results with similar findings obtained for prepandemic SARS. Methods We retrieved data for MERS-CoV clusters from the WHO summary and subsequent reports, and published descriptions of cases, and took into account 55 of the 64 laboratory-confirmed cases of MERS-CoV reported as of June 21, 2013, excluding cases notified in the previous 2 weeks. To assess the interhuman transmissibility of MERS-CoV, we used Bayesian analysis to estimate the basic reproduction number (R0) and compared it to that of prepandemic SARS. We considered two scenarios, depending on the interpretation of the MERS-CoV cluster-size data. Results With our most pessimistic scenario (scenario 2), we estimated MERS-CoV R0 to be 0·69 (95% CI 0·50–0·92); by contrast, the R0 for prepandemic SARS-CoV was 0·80 (0·54–1·13). Our optimistic scenario (scenario 1) yielded a MERS-CoV R0 of 0·60 (0·42–0·80). Because of recent implementation of effective contact tracing and isolation procedures, further MERS-CoV transmission data might no longer describe an entire cluster, but only secondary infections directly caused by the index patient. Hence, we calculated that, under scenario 2, eight or more secondary infections caused by the next index patient would translate into a 5% or higher chance that the revised MERS-CoV R0 would exceed 1—ie, that MERS-CoV might have pandemic potential. Interpretation Our analysis suggests that MERS-CoV does not yet have pandemic potential. We recommend enhanced surveillance, active contact tracing, and vigorous searches for the MERS-CoV animal hosts and transmission routes to human beings. Funding Agence Nationale de la Recherche (Labex Integrative Biology of Emerging Infectious Diseases), and the European Communitys Seventh Framework Programme project PREDEMICS.


Antimicrobial Agents and Chemotherapy | 2011

Recent Exposure to Caspofungin or Fluconazole Influences the Epidemiology of Candidemia: a Prospective Multicenter Study Involving 2,441 Patients

Olivier Lortholary; Marie Desnos-Ollivier; Karine Sitbon; Arnaud Fontanet; Stéphane Bretagne; Françoise Dromer

ABSTRACT A prospective multicenter surveillance program on yeast bloodstream infections was implemented in the Paris, France, area without restrictions on ward of hospitalization (intensive care unit, hematology, and surgery) or age (adults and children). The present analysis concerns 2,618 isolates collected over 7 years from 2,441 patients. Centralized species identification and antifungal susceptibility testing using the EUCAST methodology were performed. Almost 10% (232/2,441) of the patients had recently (≤30 days) been treated with antifungal drugs. We analyzed the effect of recent exposure to fluconazole (n = 159) or caspofungin (n = 61) on the proportions of the five major Candida species. For both drugs, preexposure was associated with a decreased prevalence of Candida albicans in favor of less drug-susceptible species (C. glabrata and C. krusei for the former and C. parapsilosis and, to a lesser extent, C. glabrata and C. krusei for the latter; P = 0.001). In the multivariate analysis, the risk of being infected with an isolate with decreased susceptibility to fluconazole was independently associated with an age of ≥15 years (odds ratio [OR] = 2.45; 95% confidence interval [CI] = 1.39 to 4.31; P = 0.002) and with recent exposure to fluconazole (OR = 2.17; 95% CI = 1.51 to 3.13; P < 0.001), while the risk of being infected with an isolate with decreased susceptibility to caspofungin was independently associated with an age <15 years (OR = 2.53; 95% CI = 1.43 to 4.48; P = 0.001) and with recent exposure to caspofungin (OR = 4.79; 95% CI = 2.47 to 9.28; P < 0.001). These findings could influence future recommendations for the management of candidemia.


AIDS | 2004

Epidemiology of HIV-associated cryptococcosis in France (1985-2001): comparison of the pre- and post-HAART eras.

Françoise Dromer; Simone Mathoulin-Pélissier; Arnaud Fontanet; Olivier Ronin; B. Dupont; Olivier Lortholary

Objective: To analyse the epidemiological evolution of cryptococcosis in France after the introduction of highly active antiretroviral therapy (HAART). Design: Retrospective study of cryptococcosis cases recorded at the National Reference Center for Mycoses in France since 1985. Methods: Using the national surveillance data, we reviewed 1644 cases of HIV-associated cryptococcosis diagnosed in France (population, 59 million) between 1985 and 2001 and compared them to 335 cases recorded in HIV-negative patients. Results: The total number of cryptococcosis cases evolved in parallel to that recorded for HIV-infected patients. Changes occurring after HAART introduction were analysed. A negative binomial regression model established a 46% decrease of the incidence of cryptococcosis during the post-HAART era (1997–2001, n = 292) compared to the pre-HAART era (1985–1996, n = 1352). According to multivariate analysis, African origin, older age, heterosexual HIV contamination, no previous AIDS-defining illness, and no previous HIV infection diagnosis were variables independently associated with an increased risk of cryptococcosis during the post-HAART era. During the same period, the characteristics of the HIV-negative population did not change. Conclusions: Our analysis of the national surveillance identified demographic factors associated with an increased risk of cryptococcosis in the post-HAART era suggesting that failure to consult and considering oneself not at risk were determinant in the current epidemiology of HIV-related cryptococcosis in France.


Journal of Clinical Investigation | 2011

Evidence for an antagonist form of the chemokine CXCL10 in patients chronically infected with HCV

Armanda Casrouge; Jérémie Decalf; Mina Ahloulay; Cyril Lababidi; H. Mansour; Anaïs Vallet-Pichard; Vincent Mallet; Estelle Mottez; James Mapes; Arnaud Fontanet; Stanislas Pol; Matthew L. Albert

Chronic infection with hepatitis C virus (HCV) is a major public health problem, with nearly 170 million infected individuals worldwide. Current treatment for chronic infection is a combination of pegylated IFN-α2 and ribavirin (RBV); however, this treatment is effective in fewer than 50% of patients infected with HCV genotype 1 or 4. Recent studies identified the chemokine CXCL10 (also known as IP-10) as an important negative prognostic biomarker. Given that CXCL10 mediates chemoattraction of activated lymphocytes, it is counterintuitive that this chemokine correlates with therapeutic nonresponsiveness. Herein, we offer new insight into this paradox and provide evidence that CXCL10 in the plasma of patients chronically infected with HCV exists in an antagonist form, due to in situ amino-terminal truncation of the protein. We further demonstrated that dipeptidyl peptidase IV (DPP4; also known as CD26), possibly in combination with other proteases, mediates the generation of the antagonist form(s) of CXCL10. These data offer what we believe to be the first evidence for CXCL10 antagonism in human disease and identify a possible factor contributing to the inability of patients to clear HCV.


Journal of Viral Hepatitis | 2012

HCV burden of infection in Egypt: results from a nationwide survey.

J. Guerra; M. Garenne; Mostafa K. Mohamed; Arnaud Fontanet

Summary.  Egypt is the country with the largest hepatitis C virus (HCV) epidemic in the world. In 2008, a Demographic Health Survey (DHS) was carried out in Egypt, providing for the first time a unique opportunity for HCV antibody testing on a nationwide representative sample of individuals. Consenting individuals answered a questionnaire on socio‐demographic characteristics and iatrogenic exposures, before providing a blood sample for HCV antibody testing by enzyme‐linked immunosorbent assay. Factors independently associated with HCV infection were examined through multivariate logistic regression models. Of 12 780 eligible subjects aged 15–59 years, 11 126 (87.1%) agreed to participate and provided a blood sample. HCV antibody prevalence nationwide was 14.7% (95% CI 13.9–15.5%) in this age group. HCV antibody prevalence gradually increased with age, reaching, in the 50–59 years age group, 46.3% and 30.8% in males and females, respectively. It was higher in males compared to females (17.4% versus 12.2%, respectively, P < 0.001), and in rural compared to urban areas (18.3% versus 10.3%, respectively, P < 0.001). In multivariate analysis, age, male sex, poverty, past history of intravenous anti‐schistosomiasis treatment, blood transfusion, and living outside of the Frontier Governorates were all significantly associated with an increased risk of HCV infection. In addition, in urban areas, lack of education and being circumcised for females were associated with an increased risk of HCV infection. This study confirmed on a nationwide representative sample the very high HCV antibody prevalence in Egypt. It stresses the urgent need for strengthening prevention efforts, and bringing down the costs of antiviral drugs for countries like Egypt, where the people in the most precarious situations are also those most likely to be infected by the virus.


Journal of Acquired Immune Deficiency Syndromes | 2007

Prevalence, determinants of positivity, and clinical utility of cryptococcal antigenemia in Cambodian HIV-infected patients.

Romain Micol; Olivier Lortholary; Borann Sar; Didier Laureillard; Chanchhaya Ngeth; Jean-Philippe Dousset; Hak Chanroeun; Laurent Ferradini; Philippe J Guerin; Fran oise Dromer; Arnaud Fontanet

Objectives:To determine the prevalence, determinants of positivity, and clinical utility of serum cryptococcal polysaccharide (CPS) antigen testing among HIV-infected patients in 2004 in Cambodia, an area highly endemic for cryptococcosis. Methods:All HIV-infected patients with a CD4+ count <200 cells/mm3 attending 1 of 2 Phnom Penh hospitals for the first time were systematically screened for serum CPS. Patients with positive test results were further investigated to identify those with cryptococcal meningitis (CM), pulmonary cryptococcosis, or isolated positive cryptococcal antigenemia (IPCA). Results:The median (interquartile range [IQR]) CD4+ count of 327 enrolled patients was 24 (IQR: 8 to 65) cells/mm3. The prevalence of cryptococcal infection was 59 (18.0%) of 327 cases, of which 41 were CM and 10 were IPCA. In the absence of serum CPS detection, 17 (28.8%) of 59 cryptococcal infections would have been missed on the day of consultation. In patients with no specific symptoms of meningoencephalitis, the prevalence of positive serum CPS detection was 32 (10.8%) of 295 cases. Countryside residence (adjusted odds ratio [AOR] = 3.6), headache (AOR = 3.2), body mass index <15.4 kg/m2 (AOR = 3.4), CD4+ count <50 cells/mm3 (AOR = 4.0), and male gender (marginally, AOR = 2.1) were all independently associated with a positive test result. Conclusion:Serum CPS screening among AIDS patients with a CD4+ count <100 cells/mm3 is useful in areas highly endemic for cryptococcosis, allowing early diagnosis and treatment of this opportunistic infection.

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Matthew L. Albert

French Institute of Health and Medical Research

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Stanislas Pol

Paris Descartes University

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