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Yanne Michel,
Kenda Saloum,
Claire Tournier,
Béatrice Quinet,
Ludovic Lassel,
Alice Pérignon,
Emmanuel Grimprel,
Ricardo Carbajal, Astrid Vabret,
François Freymuth,
Antoine Garbarg-Chenon,
Aurélie Schnuriger
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ABSTRACT: During the 2011 measles outbreak in Paris (France), patients with clinical suspicion of measles were tested for virological confirmation of measles virus (MV) infection. To assess the practical value of molecular diagnosis in an epidemic setting, 171 oral fluid samples and 235 serum samples collected from 270 patients were tested prospectively for MV-RNA using a novel one-step real-time RT-PCR assay including an internal control. Serum samples were also tested for MV-specific IgG and IgM antibodies. MV infection was confirmed by detection of MV-RNA and/or MV-IgM for 229 of the 270 patients. The results for the 102 cases with both serum and oral fluid samples available were used to compare the techniques. The detection rate of MV-RNA by RT-PCR was 98% (100/102) for oral fluid and 95% (97/102) for serum samples. The detection rate of MV-IgM was 85% (87/102). Negative MV-IgM results were observed mostly for serum samples collected early after the onset of the rash. A MV-RNA standard of known concentration obtained by in vitro transcription was used to quantify MV-RNA in samples. MV-RNA copy numbers were significantly higher in oral fluid than in serum samples, but did not correlate with time of sampling (within 1 week after the onset of the rash), patient age, or vaccination status. During the early stage of infection, the MV-RNA viral load in serum was lower in patients positive than in those negative for MV-IgG. In conclusion, the one-step real-time RT-PCR assay is a simple and sensitive tool suitable for MV diagnosis within hours. J. Med. Virol. © 2013 Wiley Periodicals, Inc.
Journal of Medical Virology 01/2013; · 2.82 Impact Factor
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ABSTRACT: Human coronaviruses are associated with upper respiratory tract infections that occasionally spread to the lungs and other organs. Although airway epithelial cells represent an important target for infection, the respiratory epithelium is also composed of an elaborate network of dendritic cells (DCs) that are essential sentinels of the immune system, sensing pathogens and presenting foreign antigens to T lymphocytes. In this report, we show that in vitro infection by human coronavirus 229E (HCoV-229E) induces massive cytopathic effects in DCs, including the formation of large syncytia and cell death within only few hours. In contrast, monocytes are much more resistant to infection and cytopathic effects despite similar expression levels of CD13, the membrane receptor for HCoV-229E. While the differentiation of monocytes into DCs in the presence of granulocyte-macrophage colony-stimulating factor and interleukin-4 requires 5 days, only 24 h are sufficient for these cytokines to sensitize monocytes to cell death and cytopathic effects when infected by HCoV-229E. Cell death induced by HCoV-229E is independent of TRAIL, FasL, tumor necrosis factor alpha, and caspase activity, indicating that viral replication is directly responsible for the observed cytopathic effects. The consequence of DC death at the early stage of HCoV-229E infection may have an impact on the early control of viral dissemination and on the establishment of long-lasting immune memory, since people can be reinfected multiple times by HCoV-229E.
Journal of Virology 05/2012; 86(14):7577-87. · 5.40 Impact Factor
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ABSTRACT: Viral respiratory infections are common in infants and can be severe. The new pandemic influenza virus H1N1v2009 was feared to cause particularly severe outcomes.
This study aimed at evaluating the impact of H1N1v2009 on the viral epidemiology, the clinical presentation and the severity of respiratory infections in infants.
This prospective epidemiologic study included all infants <2 years of age, both inpatients and outpatients, presenting with respiratory symptoms, from November 2009 through April 2010, at the pediatric emergency department of the University Hospital of Caen, France. A nasal swab was taken for viral detection and analyzed by immunofluorescence and, if negative, polymerase chain reaction. Severe respiratory infection was defined by a score of respiratory severity.
One thousand twenty-one infectious episodes with a respiratory sample met inclusion criteria. Eight hundred thirty-four samples (81.7%) were positive. The viruses with the highest incidence were the respiratory syncytial virus (34.2%), the rhinoviruses (23.9%), the coronaviruses (9.3%) and H1N1v2009 (7.7%). Of all infections, 28.6% were severe and more frequent in infants with risk factors. H1N1v2009 infections had a low risk of severe respiratory disease (odds ratios = 0.15) and hospitalization (odds ratios = 0.40) compared with the other viruses. Respiratory syncytial virus infections had a high risk of respiratory severity (odds ratios = 7.85) and were responsible for 71.4% of admissions to the intensive care unit.
Despite the modest impact of H1N1v2009 observed in this study, further surveillance is needed to detect virological factors that may increase its severity.
The Pediatric Infectious Disease Journal 04/2012; 31(8):827-31. · 3.58 Impact Factor
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ABSTRACT: During the summer of 2007, an outbreak of equine viral arteritis (EVA) occurred in Normandy (France). After investigation, a link was suggested between an EAV carrier stallion (A) and the index premise of the outbreak. The full-length nucleotide sequence analysis of a study reference strain (F27) isolated from the lung of a foal revealed a 12,710 nucleotides EAV genome with unique molecular hallmarks in the 5'UTR leader sequence and the ORF1a sequence encoding the non-structural protein 2. The evolution of the viral population in the persistently infected Stallion A was then studied by cloning ORFs 3 and 5 of the EAV genome from four sequential semen samples which were collected between 2000 and 2007. Molecular analysis of the clones confirmed the likely implication of Stallion A in the origin of this outbreak through the yearly emergence of new variants genetically similar to the F27 strain.
Virology 12/2011; 423(2):165-74. · 3.35 Impact Factor
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Fabien Miszczak,
Kathleen M Shuck,
Zhengchun Lu,
Yun Young Go,
Jianqiang Zhang,
Stephen Sells, Astrid Vabret,
Stéphane Pronost,
Guillaume Fortier,
Peter J Timoney,
Udeni B R Balasuriya
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ABSTRACT: This study showed that under specifically defined conditions with respect to nucleic acid extraction method and testing reagents, a previously described real-time reverse transcription-PCR (rRT-PCR) assay (T1 assay) provides sensitivity equal to or higher than that of virus isolation for the detection of equine arteritis virus in semen.
Journal of clinical microbiology 08/2011; 49(10):3694-6. · 4.16 Impact Factor
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Solesne Papillard-Marechal,
Vincent Enouf,
Aurélie Schnuriger, Astrid Vabret,
Edouard Macheras,
Marie-Anne Rameix-Welti,
Bernard Page,
François Freymuth,
Sylvie van der Werf,
Antoine Garbarg-Chenon,
Bertrand Chevallier,
Jean-Louis Gaillard,
Elyanne Gault
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ABSTRACT: Rapid and specific diagnosis of influenza A/B and respiratory syncytial virus (RSV) viruses is needed for optimal management of patients with acute respiratory infections. In this study, a one-step triplex real-time RT-PCR assay was developed for rapid diagnosis of influenza A/B and RSV infections to optimize diagnosis efficiency of acute respiratory infections. Cell-culture supernatants and clinical samples were used to evaluate specificity and sensitivity of the assay. The assay was used routinely during two winter epidemics for testing respiratory specimens from 2,417 patients. The limit of detection in cell-culture supernatant was 1-10 plaque forming units/input (influenza A/B) and 2 × 10(-2) 50% tissue culture infectious dose/input (RSV). In clinical samples, the assay was as sensitive as commercial molecular assays for the detection of each influenza A/B and RSV (Flu-A/B and RSV-A/B r-gene™) individually, and far more sensitive than antigen detection. During the winter 2008-2009, the assay identified 145 RSV, 42 influenza A, and one mixed RSV-influenza A infections among 298 patients. The next winter, the assay was used in two independent hospital laboratory settings. 776 patients were tested in one hospital and 1,343 in the other, resulting in 184 and 501 RSV, 133 and 150 influenza A, and 1 and 11 mixed RSV-influenza A infections, respectively, being detected. This new user-friendly assay allows rapid (within hours), effective molecular diagnosis of single or mixed infections involving influenza A (including seasonal A H1N1 and H3N2, and A(H1N1) 2009), influenza B, and RSV(A/B). The assay is very valuable for managing patients during winter epidemics when influenza and respiratory syncytial viruses co-circulate.
Journal of Medical Virology 04/2011; 83(4):695-701. · 2.82 Impact Factor
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ABSTRACT: Human metapneumovirus (hMPV) is responsible for respiratory tract disease, particularly in the young and elderly population. An epidemiological and phylogenic study was performed on children admitted to hospital with an acute lower respiratory tract infection (LRI). Data were obtained and analyzed over three consecutive winters, from 2002-2003 to 2004-2005. Each year during the winter period, from November to March, 2,415 nasal swabs were tested by a direct immunofluorescence assay (DFA) for influenza viruses A and B, respiratory syncytial virus, parainfluenza viruses, and adenoviruses. Rhinoviruses, enteroviruses, and coronaviruses OC43 and 229E were detected by RT-PCR. A RT-PCR designed for the M gene was performed on negative samples for hMPV detection and phylogenic analyses. For the three consecutive winters, hMPV represented 10%, 22.6%, and 8.8% of virus-negative samples, respectively. In most cases, clinical symptoms indicated a LRI with a final diagnosis of bronchiolitis. During the winter of 2003-2004, all viral clusters (A1, A2, B1, and B2) that circulated in France shifted progressively from the A group to the B group. This study determined the prevalence of hMPV in Normandy, its clinical impact and permitted the analysis of the molecular evolution during the successive outbreaks.
Journal of Medical Virology 03/2011; 83(3):517-24. · 2.82 Impact Factor
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Krzysztof Pyrc,
Amy C Sims,
Ronald Dijkman,
Maarten Jebbink,
Casey Long,
Damon Deming,
Eric Donaldson, Astrid Vabret,
Ralph Baric,
Lia van der Hoek,
Raymond Pickles
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ABSTRACT: Culturing newly identified human lung pathogens from clinical sample isolates can represent a daunting task, with problems ranging from low levels of pathogens to the presence of growth suppressive factors in the specimens, compounded by the lack of a suitable tissue culture system. However, it is critical to develop suitable in vitro platforms to isolate and characterize the replication kinetics and pathogenesis of recently identified human pathogens. HCoV-HKU1, a human coronavirus identified in a clinical sample from a patient with severe pneumonia, has been a major challenge for successful propagation on all immortalized cells tested to date. To determine if HCoV-HKU1 could replicate in in vitro models of human ciliated airway epithelial cell cultures (HAE) that recapitulate the morphology, biochemistry, and physiology of the human airway epithelium, the apical surfaces of HAE were inoculated with a clinical sample of HCoV-HKU1 (Cean1 strain). High virus yields were found for several days postinoculation and electron micrograph, Northern blot, and immunofluorescence data confirmed that HCoV-HKU1 replicated efficiently within ciliated cells, demonstrating that this cell type is infected by all human coronaviruses identified to date. Antiserum directed against human leukocyte antigen C (HLA-C) failed to attenuate HCoV-HKU1 infection and replication in HAE, suggesting that HLA-C is not required for HCoV-HKU1 infection of the human ciliated airway epithelium. We propose that the HAE model provides a ready platform for molecular studies and characterization of HCoV-HKU1 and in general serves as a robust technology for the recovery, amplification, adaptation, and characterization of novel coronaviruses and other respiratory viruses from clinical material.
Journal of Virology 11/2010; 84(21):11255-63. · 5.40 Impact Factor
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ABSTRACT: Acute respiratory infections are a major cause of mortality and morbidity worldwide. Using multiplex PCR/RT-PCR methods for the detection of 18 respiratory viruses, the circulation of those viruses during 3 consecutive dry seasons in Cambodia was described. Among 234 patients who presented with influenza-like illness, 35.5% were positive for at least one virus. Rhinoviruses (43.4%), parainfluenza (31.3%) viruses and coronaviruses (21.7%) were the most frequently detected viruses. Influenza A virus, parainfluenza virus 4 and SARS-coronavirus were not detected during the study period. Ninety apparently healthy individuals were included as controls and 10% of these samples tested positive for one or more respiratory viruses. No significant differences were observed in frequency and in virus copy numbers for rhinovirus detection between symptomatic and asymptomatic groups. This study raises questions about the significance of the detection of some respiratory viruses, especially using highly sensitive methods, given their presence in apparently healthy individuals. The link between the presence of the virus and the origin of the illness is therefore unclear.
Journal of Medical Virology 10/2010; 82(10):1762-72. · 2.82 Impact Factor
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ABSTRACT: Human parvovirus B19 (PVB19) infection is occasionally associated with acute myocarditis. Three cases of children with PVB19 virus-associated myocarditis occurred in a very short period and the same geographical region.
To elucidate if virological factors could be responsible for determining the course of infection, a molecular epidemiologic investigation was performed.
The diagnosis of myocarditis was established by histology or echocardiography. In the three cases, the PVB19 DNA was detected in different samples. Eight different regions were amplified by PCR using a high fidelity Taq polymerase and sequenced on both strands. Phylogenetic analyses were performed. First, the genotypes of the PVB19 strains were determined, then the intra-patient viral variability was analysed by sequencing PVB19 detected in different specimens sampled from the same patient at the same moment.
Nearly complete sequences of the PVB19 virus (4265nt) were obtained from different samples in the three patients. The phylogenetic analyses showed that PVB19 strains identified clustered with genotype 1a PVB19 strains referenced in GenBank. When compared to the referenced strain NC_000883, the number of substitutions (transitions and transversions) were as follows: 58 for Caen.FRA/19.09, 74 for Caen.FRA/21.09 and 60 for Caen.FRA/24.09. The strains isolated from the same patient showed 100% of similarity.
Viral myocarditis is a frequently unrecognized cause of post-inflammatory cardiomyopathy. The detailed molecular analyses do not give rise to virological markers associated with myocarditis in these children.
Journal of clinical virology: the official publication of the Pan American Society for Clinical Virology 10/2010; 50(1):61-4. · 3.12 Impact Factor
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ABSTRACT: The disease burden caused by recently identified respiratory viruses like HCoV-NL63 is unknown.
We determined the burden of disease due to HCoV-NL63 infections using the population-based PRI.DE cohort of children under the age of 3 with lower respiratory tract infections (LRTIs).
In total 1756 respiratory samples, from hospitalized children or children who visited the outpatient clinic, were tested for HCoV-NL63. Sampling covered a period of 2 years and the frequency of infection in different years was compared to other Western European studies that tested for this virus in 2 or more consecutive years.
Sixty-nine samples were HCoV-NL63 positive, 35 were with high loads, and of these 25 were single HCoV-NL63 infections. Based on the number of children with high HCoV-NL63 infection and no additional infection, the overall annual incidence in outpatients was 7 per 1000 children per year (95% confidence interval (CI) 3-13 per 1000 children per year), which can be extrapolated to an absolute number of 16,929 visits to the physician due to an HCoV-NL63 infection in Germany per year. The estimated hospitalization rate is 22 per 100,000 children (95% CI: 7-49 per 100,000 children per year). This number reflects 522 HCoV-NL63 children in Germany per year. A large year-to-year difference in HCoV-NL63 infection frequency was observed. Combining these data with those of other studies in Western Europe revealed that HCoV-NL63 infections follow a 2-year inter-epidemic period with peaks of infection in the winters of 2000/2001, 2002/2003 and 2004/2005 (p<0.0001).
HCoV-NL63 infection in children below 3 years of age often requires a visit to the physician in an outpatient clinic, especially during peak-years, but hospitalizations are relatively infrequent.
Journal of clinical virology: the official publication of the Pan American Society for Clinical Virology 03/2010; 48(2):104-8. · 3.12 Impact Factor
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ABSTRACT: Serum procalcitonin (PCT) is considered useful in predicting the likeliness of developing bacterial infections in emergency setting. In this study, we describe PCT levels overtime and their relationship with bacterial infection in chronic obstructive pulmonary disease (COPD) critically ill patients with pneumonia.
We conducted a prospective cohort study in an ICU of a University Hospital. All consecutive COPD patients admitted for pneumonia between September 2005 and September 2006 were included. Respiratory samples were tested for the presence of bacteria and viruses. Procalcitonin was sequentially assessed and patients classified according to the probability of the presence of a bacterial infection.
Thirty four patients were included. The PCT levels were assessed in 32/34 patients, median values were: 0.493 microg/L [IQR, 0.131 to 1.471] at the time of admission, 0.724 microg/L [IQR, 0.167 to 2.646] at six hours, and 0.557 microg/L [IQR, 0.123 to 3.4] at 24 hours. The highest PCT (PCTmax) levels were less than 0.1 microg/L in 3/32 (9%) patients and greater than 0.25 microg/L in 22/32 (69%) patients, suggesting low and high probability of bacterial infection, respectively. Fifteen bacteria and five viruses were detected in 15/34 (44%) patients. Bacteria were not detected in patients with PCTmax levels < 0.1 microg/L. In contrast, bacteria were detected in 4/7 (57%) patients estimated unlikely to have a bacterial infection by PCT levels (PCTmax > 0.1 and < 0.25 microg/L).
Based on these results we suggest that a PCT level cut off > 0.1 microg/L may be more appropriate than 0.25 microg/L (previously proposed for non severe lower respiratory tract infection) to predict the probability of a bacterial infection in severe COPD patients with pneumonia. Further studies testing procalcitonin-based antibiotic strategies are needed in COPD patients with severe pneumonia.
BMC Infectious Diseases 09/2009; 9:157. · 3.12 Impact Factor
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Grégory Caignard,
Anastassia V Komarova,
Mehdi Bouraï,
Thomas Mourez,
Yves Jacob,
Louis M Jones,
Flore Rozenberg, Astrid Vabret,
François Freymuth,
Frédéric Tangy,
Pierre-Olivier Vidalain
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ABSTRACT: A number of paramyxoviruses are responsible for acute respiratory infections in children, elderly and immuno-compromised individuals, resulting in airway inflammation and exacerbation of chronic diseases like asthma. To understand the molecular pathogenesis of these infections, we searched for cellular targets of the virulence protein C of human parainfluenza virus type 3 (hPIV3-C). We found that hPIV3-C interacts directly through its C-terminal domain with STAT1 and GRB2, whereas C proteins from measles or Nipah viruses failed to do so. Binding to STAT1 explains the previously reported capacity of hPIV3-C to block type I interferon signaling, but the interaction with GRB2 was unexpected. This adaptor protein bridges Epidermal Growth Factor (EGF) receptor to MAPK/ERK pathway, a signaling cascade recently found to be involved in airway inflammatory response. We report that either hPIV3 infection or transient expression of hPIV3-C both increase cellular response to EGF, as assessed by Elk1 transactivation and phosphorylation levels of ERK1/2, 40S ribosomal subunit protein S6 and translation initiation factor 4E (eIF4E). Furthermore, inhibition of MAPK/ERK pathway with U0126 prevented viral protein expression in infected cells. Altogether, our data provide molecular basis to explain the role of hPIV3-C as a virulence factor and determinant of pathogenesis and demonstrate that Paramyxoviridae have evolved a single virulence factor to block type I interferon signaling and to boost simultaneous cellular response to growth factors.
PLoS Pathogens 09/2009; 5(9):e1000587. · 9.13 Impact Factor
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ABSTRACT: A method was developed for the detection and quantitation of HAdV (human adenovirus) and HBoV (human bocavirus) based on a duplex real-time PCR, the AB PCR, using a Smartcycler instrument. A control real-time PCR was carried out on albumin DNA to standardise the non-homogenous respiratory samples. No cross-reactivity was observed with viruses or bacteria that could be found in the respiratory tract. The diagnosis rate using the AB PCR on clinical samples was 10.7%: 3.4% for HBoV detection, 6.9% for HAdV detection and 0.3% double detection HBoV-HAdV. The clinical and epidemiological characteristics of the HAdV- and HBoV-infected patients were evaluated. In the HAdV-positive group and the HBoV-positive group the samples were classified according to the severity of the disease. The HAdV viral load did not appear to be linked to the severity of the disease. Conversely, the difference between the two HBoV groups, severe and non-severe, was significant statistically when the comparison was based on the viral load (P=0.006) or after adjustment of the viral load to the number of cells in the samples (P=0.02).
Journal of virological methods 09/2009; 162(1-2):119-25. · 2.13 Impact Factor
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Wei Wang,
Peijun Ren,
Jun Sheng,
Sek Mardy,
Huajie Yan,
Jing Zhang,
Lili Hou, Astrid Vabret,
Philippe Buchy,
Francois Freymuth,
Vincent Deubel
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ABSTRACT: A 4-tube multiplex RT-PCR (mRT-PCR), which showed higher sensitivity over conventional methods, was previously developed for the diagnosis of 14 viral pathogens of the respiratory tract. Herein the mRT-PCR was compared to the commercial Luminex mPCR-microsphere flow cytometry assay (Resplex II) which allows the detection of 12 different viruses. Eleven different viruses were identified in 91 nasopharyngeal swabs of children with acute respiratory infection, influenza A (IAV) and B, respiratory syncytial virus (RSV), human rhinovirus (hRhV), human echovirus, parainfluenza viruses (PIV) 1, 2, 3 and 4, human metapneumovirus (hMPV), and human coronavirus NL63. The results of the two techniques showed 53 and 40 positive patients by the Resplex II assay and mRT-PCR, respectively, with a concordance in 35 positive and 33 negative patients (74.7%). Individual RT-PCR tests were performed to control viruses not simultaneously detected by the two multiplex assays. The major virus misdiagnosed by mRT-PCR was IAV whereas the major viruses misdiagnosed by Resplex II were PIV1, 3 and 4. The mRT-PCR remains a simple, rapid, and specific assay for the specific detection of respiratory viruses, and can be easily implemented with standards in clinical laboratories at a low cost.
Journal of virological methods 08/2009; 162(1-2):40-5. · 2.13 Impact Factor
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ABSTRACT: The objectives of this study are to assess the frequency of human bocavirus (HBoV) infection in hospitalised children and to study the clinical symptoms associated with the detection of HBoV.
Two groups of hospitalised children were included in this study: group 1 consisted of 1946 children hospitalised from 1st September 2004 to 30th May 2005, and group 2 consisted of 448 children hospitalised from 1st November 2003 to 30th March 2004. The respiratory specimens were tested by polymerase chain reaction.
In the first group, HBoV was detected by polymerise chain reaction in 11/828 (1.3%) of nasal specimens that tested negative for other respiratory viruses. One child tested positive for HBoV in both a nasal aspirate and stool sample. In the second group, nasal specimens were tested for all respiratory viruses, including HBoV. The presence of HBoV infection was detected in seven children (1.6%). Detection of a mixed viral population was observed in four of these children. The main symptoms in children infected with HBoV were rhinitis (50%), cough (45%), dyspnoea (28%), wheezing (28%), fever (23%) and diarrhoea (22%). The final clinical diagnoses were bronchiolitis (seven children), rhinopharyngitis (five children), the exacerbation of asthma (two children) and pneumonia (one child). Moreover, four children have associated gastroenteritis.
These results contribute to the interest in the HBoV detection in children. HBoV detection in hospitalised children with or without any other respiratory virus detection was essentially associated with lower respiratory tract infection and in a lower score with upper respiratory tract infection and gastroenteritis.
Journal of Paediatrics and Child Health 03/2009; 45(3):149-53. · 1.28 Impact Factor
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Christophe Marguet,
Marc Lubrano,
Marie Gueudin,
Pascal Le Roux,
Antoine Deschildre,
Chantal Forget,
Laure Couderc,
Daniel Siret,
Marie-Dominique Donnou,
Michael Bubenheim, Astrid Vabret,
François Freymuth
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ABSTRACT: RT amplification reaction has revealed that various single viruses or viral co-infections caused acute bronchiolitis in infants, and RV appeared to have a growing involvement in early respiratory diseases. Because remaining controversial, the objective was to determine prospectively the respective role of RSV, RV, hMPV and co-infections on the severity of acute bronchiolitis in very young infants.
209 infants (median age: 2.4 months) were enrolled in a prospective study of infants <1 year old, hospitalized for a first episode of bronchiolitis during the winter epidemic season and with no high risk for severe disease. The severity was assessed by recording SaO(2)% at admission, a daily clinical score (scale 0-18), the duration of oxygen supplementation and the length of hospitalization. Viruses were identified in 94.7% by RT amplification reaction: RSV only (45.8%), RV only (7.2%), hMPV only (3.8%), dual RSV/RV (14.3%), and other virus only (2%) or coinfections (9%). RV compared respectively with RSV and dual RSV/RV infection caused a significant less severe disease with a lower clinical score (5[3.2-6] vs. 6[4-8], p = 0.01 and 5.5[5-7], p = 0.04), a shorter time in oxygen supplementation (0[0-1] days vs. 2[0-3] days, p = 0.02 and 2[0-3] days, p = 0.03) and a shorter hospital stay (3[3-4.7] days vs.6 [5-8] days, p = 0.001 and 5[4-6] days, p = 0.04). Conversely, RSV infants had also longer duration of hospitalization in comparison with RSV/RV (p = 0.01) and hMPV (p = 0.04). The multivariate analyses showed that the type of virus carried was independently associated with the duration of hospitalization.
This study underlined the role of RV in early respiratory diseases, as frequently carried by young infants with a first acute bronchiolitis. RSV caused the more severe disease and conversely RV the lesser severity. No additional effect of dual RSV/RV infection was observed on the severity.
PLoS ONE 02/2009; 4(2):e4596. · 4.09 Impact Factor
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ABSTRACT: Antibiotics are recommended for severe acute exacerbation of chronic obstructive pulmonary disease (AECOPD) admitted to intensive care units (ICU). Serum procalcitonin (PCT) could be a useful tool for selecting patients with a lower probability of developing bacterial infection, but its measurement has not been investigated in this population.
We conducted a single center prospective cohort study in consecutive COPD patients admitted to the ICU for AECOPD between September 2005 and September 2006. Sputum samples or tracheal aspirates were tested for the presence of bacteria and viruses. PCT levels were measured at the time of admittance, six hours, and 24 hours using a sensitive immunoassay.
Thirty nine AECOPD patients were included, 31 of which (79%) required a ventilator support at admission. The median [25%-75% interquartile range] PCT level, assessed in 35/39 patients, was: 0.096 microg/L [IQR, 0.065 to 0.178] at the time of admission, 0.113 microg/L [IQR, 0.074 to 0.548] at six hours, and 0.137 microg/L [IQR, 0.088 to 0.252] at 24 hours. The highest PCT (PCTmax) levels were less than 0.1 microg/L in 14/35 (40%) patients and more than 0.25 microg/L in 10/35 (29%) patients, suggesting low and high probability of bacterial infection, respectively. Five species of bacteria and nine species of viruses were detected in 12/39 (31%) patients. Among the four patients positive for Pseudomonas aeruginosa, one had a PCTmax less than 0.25 microg/L and three had a PCTmax less than 0.1 microg/L. The one patient positive for Haemophilus influenzae had a PCTmax more than 0.25 microg/L. The presence or absence of viruses did not influence PCT at time of admission (0.068 vs 0.098 microg/L respectively, P = 0.80).
The likelihood of bacterial infection is low among COPD patients admitted to ICU for AECOPD (40% with PCT < 0.1 microg/L) suggesting a possible inappropriate use of antibiotics. Further studies are necessary to assess the impact of a procalcitonin-based therapeutic strategy in critically ill COPD patients.
BMC Infectious Diseases 10/2008; 8:145. · 3.12 Impact Factor
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Journal of Clinical Virology 06/2008; 42(1):70-1. · 3.97 Impact Factor
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ABSTRACT: This study has two objectives: to study the clinical symptoms associated with the detection of the four human coronaviruses (HCoVs), 229E, OC43, NL63 and HKU1 types, in the respiratory specimens sampled from hospitalised children in France between September 2004 and May 2005; and to develop a multiplex reverse transcription polymerase chain reaction (RT-PCR) assay allowing for the simultaneous detection of the four HCoVs.
1002 respiratory specimens were tested for HCoVs. The clinical and epidemiological data were compared on the basis of the type HCoV infection.
A hundred coronaviruses, 33 NL63, 2229E, 27 OC43 and 38 HKU1, were detected in 97 (9.8%) of 1002 samples negative in routine tests. The clinical and epidemiological characteristics of the study children were compared in three groups, 24 OC43-, 27 NL63- and 34 HKU1-infected children. HCoVs were identified mainly in children with upper and lower respiratory tract infections (50.5% vs. 29.4%). The significant difference in clinical presentation between the three coronavirus groups was the very low association between lower respiratory tract illness and HKU1 detection.
HCoV detection in hospitalised children without any other respiratory virus detection was associated with upper and a significant rate of lower respiratory tract illness. The four types of HCoVs were detected, and new types NL63 and HKU1 represented a substantial portion of detection. The multiplex RT-PCR enabled a sensitive one-time detection and the characterisation of all of the known HCoV types with the exception severe acute respiratory syndrome-coronavirus.
Journal of Paediatrics and Child Health 05/2008; 44(4):176-81. · 1.28 Impact Factor
