Novel UL23 and UL30 substitutions in HSV1 and HSV2 viruses related to polymorphism or drug resistance.

Data on herpes simplex virus (HSV) polymorphism as well as acyclovir (ACV) and foscarnet (FOS) resistance mutations are not exhaustive and may hinder accurate diagnosis by next-generation sequencing (NGS). Here, we report novel UL23 and UL30 substitutions for HSV1 and HSV2 identified in immunocompromised patients treated for hematological malignancies during the last 6 years of HSV resistance surveillance at the University Hospital of Lyon. For HSV1, 35 novel UL23 substitutions and 52 novel UL30 substitutions were identified. For HSV2, 2 novel UL23 substitutions and 12 novel UL30 substitutions were identified. These results allow to complete the database of HSV1 and HSV2 substitutions, related either to polymorphism or to ACV and FOS resistance.

Increased detection of Mycoplasma pneumoniae infection in children, Lyon, France, 2010 to 2011.

Recent reports from several northern European countries indicate an increase in detection of Mycoplasma pneumoniae infection in the past two years, notably in children aged 5­15 years. Analysis of our laboratory database showed a similar pattern, with a higher proportion of respiratory samples positive for M. pneumonia by real-time PCR in paediatric patients aged 5­15 years. Our data indicate that in 2010 and 2011, France experienced the first epidemic peak of M. pneumonia infection since 2005.

A report on the large measles outbreak in Lyon, France, 2010 to 2011.

In 2010 and 2011, the city of Lyon, located in the Rhône-Alpes region (France), has experienced one of the highest incidences of measles in Europe. We describe a measles outbreak in the Lyon area, where cases were diagnosed at Lyon University hospitals (LUH) between 2010 and mid-2011. Data were collected from the mandatory notification system of the regional public health agency, and from the virology department of the LUH. All patients and healthcare workers who had contracted measles were included. Overall, 407 cases were diagnosed, with children of less than one year of age accounting for the highest proportion (n=129, 32%), followed by individuals between 17 and 29 years-old (n=126, 31%). Of the total cases, 72 (18%) had complications. The proportions of patients and healthcare workers who were not immune to measles were higher among those aged up to 30 years. Consequently, women of childbearing age constituted a specific population at high risk to contract measles and during this outbreak, 13 cases of measles, seven under 30 years-old, were identified among pregnant women. This study highlights the importance of being vaccinated with two doses of measles vaccine, the only measure which could prevent and allow elimination of the disease.

[Parvovirus B19 infections in adults]. / Infection de l'adulte à Parvovirus.

Acute Parvovirus B19 (PVB19) infection is responsible for erythema infectiosum in children and non-specific polyarthralgias in immunocompetent adults associated with skin lesions and rarer manifestations (hepatic, neurological, cardiac or nephrological). In immunocompromised patients, cytopenias are more frequent and in some cases, viremia persists and is responsible for PVB19 chronic infection. PVB19 is responsible for pure red cell aplasia during chronic hemolytic diseases. Acute PVB19 infection is a differential diagnosis of some autoimmune diseases and has been suspected to be a trigger for some autoimmune diseases because of its ability to promote the emergence of autoimmune markers. Mechanisms of molecular mimicry, induction of apoptosis and activation of enzymes have been demonstrated, explaining in part the production of autoantibodies during infection. However, the demonstration of a causal relationship in the triggering of autoimmune disease remains to be done. This review provides a synthesis of the PVB19 infection clinical data in adults with a particular focus on these links with autoimmunity.

Phylogenetic evidence for a recent spread of two populations of human enterovirus 71 in European countries.

Human enterovirus 71 (EV-71) is a cause of seasonal epidemics of hand, foot and mouth disease, and of less common but severe neurological manifestations. Uncertainty persists regarding the circulation of virus populations in several geographical areas and the timescale of their dissemination. We determined EV-71 sequences at loci 1D (VP1 capsid protein) and 3CD (non-structural proteins) in 86 strains recovered in Austria, France and Germany and performed an evolutionary genetic study of extant virus populations. Phylogenetic analyses positioned 78 of the 86 sequences within two clades among subgenogroups C1 and C2. A minor sequence cluster was assigned to subgenogroup C4. Analyses incorporating the available sequences estimated the substitution rate in genogroup C at 3.66 x 10(-3) and 4.46 x 10(-3) substitutions per site year(-1) for loci 1D and 3CD, respectively, assuming a relaxed molecular-clock model for sequence evolution. Most of the 'European' strains belonged to clades C1b and C2b, which originated in 1994 [95 % confidence interval (CI), 1992.7-1995.8] and 2002 (95 % CI, 2001.6-2003.8), respectively. Estimates of divergence times for locus 3CD were consistent with those measured for locus 1D. Intertwining between clades representing EV-71 subgenogroups and clades corresponding to other enterovirus types (notably early coxsackievirus A prototype strains) in the 3CD phylogeny is highly indicative of ancestral recombination events. Incongruent phylogenetic patterns estimated for loci 1D and 3CD show that a single tree cannot model the epidemic history of circulating EV-71 populations. The evolutionary timescale of genogroup C estimated for both loci was measured only in decades, indicating recent dissemination.

[Epidemiology and burden of rotavirus diarrhea in day care centers in Lyon, France]. / Epidémiologie et impact de la gastroentérite aiguë à rotavirus dans les crèches municipales de la ville de Lyon - saison 2004-2005.

Rotavirus is the main cause of severe, dehydrating diarrhoea in infants and young children. In industrialized countries, pediatric rotavirus gastroenteritis (PRGE) is responsible for high morbidity, particularly among children under 3 years of age attending day care centers (DCCs). The objectives of this study were to estimate the incidence, management and cost of PRGE in DCCs. We also described the nature of group A rotavirus genotypes. This study also compared the performance of different diagnostic techniques. The study was conducted from November 2004 to May 2005. Children aged less than 36 months, attending a participating DCC at least 4 times a week were included in the study. For any episode of acute gastroenteritis (AGE), defined as the occurrence of 3 or more watery or looser than normal stools and/or forceful vomiting within a 24 h period, a fecal specimen was tested by Elisa test IDEIA Rotavirus (Dako) and the immunochromatographic test VIKIA Rota-Adeno (BioMérieux). Sequencing by RT-PCR was performed to identify the rotavirus genotype. Among the 41 DCCs contacted, 18 (43.9%) agreed to participate. Out of 966 children, 547 attended a participating DCC at least 4 times a week and met the inclusion criteria. A total of 302 were included in the study. The clinical diagnosis of AGE was confirmed and validated, by the Elisa test, in 63 fecal specimens, of which 29 (46%) were positive for rotavirus antigen, with a predominance of P[8]G9 (86%). Our results showed good sensitivity and specificity for the VIKIA and Elisa methods when compared to RT-PCR. Among the PRGE cases, 36% were male and the median age was 12.2 months. The first rotavirus case was observed in December 2004 with a peak in January 2005. The incidence of PRGE cases was 2.2 [1.4-3.0] per 100 child-months in children aged less than 36 months of age, increasing to 3.4 per 100 child-months among children aged less than 24 months. Vomiting (P<0.0005) and behavior modification (P<0.001) were significantly more frequent for PRGE cases. A total of 85.7% PRGE cases sought medical attention. In 58.3% of these cases, at least one parent had to miss work for a mean duration of 2.1 days. The total cost of rotavirus cases seeking medical attention (with or without prescribed medication, days off work for parents or additional diaper consumption) was estimated at 275.54 euros/case. The PRGE incidence rate is similar to that estimated in European studies conducted in DDC. These findings confirm that rotavirus transmission occurs not only in DCCs but within the family. This is the first study to give an estimate of the incidence and the cost of rotavirus infection in DCCs in France.

Specific binding of [3H]GBR 12783 to the dopamine neuronal carrier included in polarized membranes.

We have compared the properties of the binding to the neuronal dopamine carrier located either in polarized membranes of synaptosomes or in non polarized, classical membranes. Non-polarized membranes were prepared by sonication of the partially purified synaptosomal fraction obtained from rat striatum which was used as the source of polarized membranes. Binding experiments were carried out at 37 degrees C in Krebs Ringer related media. [3H]GBR 12783 (1-[2-(diphenylmethoxy)ethyl]4-(3-phenyl-2-[1- 3H]propenyl)piperazine) specifically bound with a nanomolar affinity to a homogeneous population of site (maximal binding site concentration: 8-10 pmol/mg protein). Pure uptake inhibitors, but not substrates, competed for the [3H]GBR 12783 binding site located in polarized membranes of synaptosomes at concentrations effective against dopamine neuronal transport. Except for [3H]GBR 12783, the replacement of Cl- by isethionate- did not result in significant change in the ability of pure uptake inhibitors to compete for the specific binding site. A reduction in the Na+ concentration from 135 to 10 mM induced a significant decrease in the inhibitory potency of GBR 12783, mazindol, nomifensine and methylphenidate. This decrease was likely to result from the presence of K+, Mg2+ and Ca2+, whose inhibitory effects were modified and/or increased by decreasing the Na+ concentration. These data indicate that the membrane polarity is not clearly involved in the binding of pure uptake inhibitors to the dopamine neuronal carrier; furthermore they underline the critical role of Na+ and K+ transmembrane gradients in both the recognition of the carrier by dopamine and its inward transport.

Complex ionic control of [3H]GBR 12783 binding to the dopamine neuronal carrier.

At 20 degrees C, [3H]GBR 12783, {1-[2-(diphenylmethoxy)ethyl]4-(3-phenyl-2-([1-3H]propenyl)-pip era zine} dissociated from the dopamine neuronal carrier present in rat striatal membranes with a t1/2 value of 27 min. At this temperature, KCI, CaCl2 and MgCl2 increased the binding dissociation, revealing that they recognize a binding site which is not mutually exclusive with that of [3H]GBR 12783. The comparison of the ability of KCl to increase the binding dissociation (by 160% at 30 mM KCl) with its potency as a binding inhibitor (Ki-2.6 +/- 0.3 mM) suggests an involvement of two recognition sites for K+ in binding inhibition, a not mutually exclusive site and another, mutually exclusive, site. Divalent cations mainly inhibited the binding via a mutually exclusive site since 3 mM Ca2+ and 10 mM Mg2+ increased the binding dissociation by 90% at 20 degrees C whereas their Ki values were 0.049 +/- 0.006 and 0.141 +/- 0.035 mM, respectively. Involvement of this mutually exclusive site was also supported by the persistence of the binding inhibition elicited by Ca2+ and Mg2+ at 0 degree C, a temperature at which they reduced the binding dissociation. At 20 degrees C, 100 mM NaCl did not modify [3H]GBR 12783 binding but it antagonized the binding dissociation elicited by inhibitory cations. Ca2+ reduced the off-rate of [3H]GBR 12783 binding at 0 degree C and in the presence of 100 mM Na+. Finally, [3H]GBR 12783-binding dissociation was increased by high 'cytosolic' K+ while 'synaptic' concentrations of Na+, K+, Ca2+, Mg2+ and Cl- were ineffective. A reduction of H2PO4-/HCO3- from 10 to 5 mM and a substitution of 5 mM H2PO4-/HCO3- by 5 mM Cl- increased the binding dissociation, suggesting that an anion-binding site could also regulate the binding.

Thermodynamics of the binding of BTCP (GK 13) and related derivatives on the dopamine neuronal carrier.

We have studied the thermodynamic properties of the binding of a coherent series of uptake inhibitors derived from BTCP (GK 13 = N-[1-(2-benzo(b)thiophenyl)cyclohexyl]piperidine) to the dopamine neuronal carrier labelled with [3H]GBR 12783 (1-[2-(diphenylmethoxy)ethyl]4-(3-phenyl-2-propenyl)-piperazine). GK 13 (30 nM) and its 2-naphthyl derivative GK 189 (15 nM) competitively inhibited the specific binding of [3H]GBR 12783 to sites present in rat striatal membranes. Hill numbers calculated for the inhibition of the specific binding of [3H]GBR 12783 by BTCP derivatives were close to 1 (range 0.79-1.18). Increasing the temperature from 0 degrees to 30 degrees C induced a decrease in the affinity of [3H]GBR 12783 and GK derivatives which was generally less pronounced than that obtained when temperature was raised from 30 degrees C to 37 degrees C. Increasing the incubation temperature led to a decrease in both enthalpy (delta H degrees) and entropy (delta S degrees). We observed at 37 degrees C a large negative enthalpy change (range -48, -79 kJ/mol) and a negative, binding unfavorable, change in entropy. This indicates that the GK derivatives binding is enthalpy-driven. Furthermore, data obtained in the present study show that changes in thermodynamic parameters are not a function of the inhibitor's affinity for the dopamine neuronal carrier and this suggests that bonds involved in the inhibitor-carrier interaction are more likely related to the carrier configuration than to the chemical structure of the inhibitor.

High burden of BK virus-associated hemorrhagic cystitis in patients undergoing allogeneic hematopoietic stem cell transplantation.

BK virus (BKV) reactivation has been increasingly associated with the occurrence of late-onset hemorrhagic cystitis (HC) after allogeneic hematopoietic SCT (allo-HSCT) resulting in morbidity and sometimes mortality. We investigated the incidence, risk factors and outcome of BKV-HC in 323 consecutive adult patients undergoing allo-HSCT over a 5-year period. BK viremia values for HC staging were evaluated, as well as the medico-economic impact of the complication. Forty-three patients developed BKV-HC. In univariate analysis, young age (P=0.028), unrelated donor (P=0.0178), stem cell source (P=0.0001), HLA mismatching (P=0.0022) and BU in conditioning regimen (P=0.01) were associated with a higher risk of developing BKV-HC. In multivariate analysis, patients receiving cord blood units (CBUs) (P=0.0005) and peripheral blood stem cells (P=0.011) represented high-risk subgroups for developing BKV-HC. BK viremia was directly correlated to HC severity (P=0.011) with a 3 to 6-log peak being likely associated with grades 3 or 4 HC. No correlation was found between BKV-HC and acute graft versus host disease or mortality rate. Patients with BKV-HC required a significantly longer duration of hospitalization (P<0.0001), more RBC (P=0.0003) and platelet transfusions (P<0.0001). Over the 5-year study period, the financial cost of the complication was evaluated at \[euro]2 376 076 ($3 088 899). Strategies to prevent the occurrence of late-onset BKV-HC after allo-HSCT are urgently needed, especially in CBU and peripheral blood stem cell recipients. BK viremia correlates with the severity of the disease. Prospective studies are required to test prophylactic approaches.

[Cytomegalovirus research using polymerase chain reaction in Posner-Schlossman syndrome]. / Intérêt de la recherche du cytomégalovirus par polymerase chain reaction dans le syndrome de Posner-Schlossman.

PURPOSE: To investigate the possible association between cytomegalovirus (CMV) infection and Posner-Schlossman syndrome using PCR. To evaluate the clinical effect of valganciclovir treatment. PATIENTS AND METHODS: Patients with anterior uveitis associated with suspected Posner-Schlossman syndrome had their aqueous humor prospectively analyzed for viral deoxyribonucleic acid by HXFL4 gene detection using quantitative real-time PCR. RESULTS: Seven patients (two females and five males from 15 to 56 years old) with clinical signs of Posner-Schlossman syndrome (anterior nongranulomatous hypertensive uveitis with anterior chamber cells, central keratic precipitates, anisocoria, without iris atrophy) were tested. Examinations of the aqueous humor by polymerase chain reaction demonstrated CMV-DNA in five patients and were negative for other herpes viruses in all patients. Two patients were treated with oral antiviral therapy (valganciclovir). Relapses occurred in all cases after cessation of therapy. DISCUSSION: Aqueous humor analysis by PCR is useful in differentiating between CMV and other herpes viruses and in making a positive etiological diagnosis in anterior hypertensive uveitis. Valganciclovir may be effective in treating CMV anterior uveitis, but its exact role should be determined in larger studies with a longer follow-up. CONCLUSION: Cytomegalovirus detection in aqueous humor using polymerase chain reaction is useful in the management of patients with Posner-Schlossman syndrome.

Pediatric neurological complications associated with the A(H1N1)pdm09 influenza infection.

BACKGROUND: Influenza-related neurological complications (INC) have been reported during seasonal flu in children. OBJECTIVES: To investigate the types, outcomes and incidence of INC occurring during the 2009 A(H1N1) pandemic, a retrospective analyze was conducted in the single French pediatric hospital of Lyon from October 2009 to February 2010. STUDY DESIGN: All children presenting with fever, influenza-like illness, respiratory distress or neurological symptoms were tested for influenza A(H1N1)pdm09 infection from respiratory specimens using real time RT-PCR. RESULTS: INC occurred in 14 A(H1N1)pdm09 positive children (7.7% of A(H1N1)pdm09 positive children admitted to hospital) with a median age of 5.1 years. Admission to the intensive care unit (ICU) was required for nine children (64.3%). Half of the children with INC had comorbidity and three had coinfection, both characteristics mainly found in children requiring the ICU. All children received oral oseltamivir treatment. Febrile seizures were observed in eight children, half of them having a chronic comorbidity (2 epilepsy, 1 nonketotic hyperglycinemia, 1 anoxic encephalopathy). Other INC, less commonly reported, included 2 cases of encephalitis, 1 encephalopathy, 1 basilar artery thrombosis, 1 myasthenic crisis and 1 coma. Eleven of the 14 children (78.6%) recovered, one had a minor disability, one child developed a locked-in syndrome and one died from complications of an acute necrotizing encephalopathy. DISCUSSION: INC can be observed even in children with no underlying disorder. It may lead to dramatic issue in a significant number of cases.

Rhinoviruses delayed the circulation of the pandemic influenza A (H1N1) 2009 virus in France.

In contrast to the experience in other European countries, the onset of the A(H1N1)2009 influenza virus epidemic was unexpectedly slow in France during the first part of autumn 2009. Our objective was to test the hypothesis that intense circulation of rhinoviruses might have reduced the probability of infection by A(H1N1)2009 virus at the beginning of autumn 2009. Systematic analysis for the detection of A(H1N1)2009 (H1N1) and human rhinovirus (HRV) was performed by RT-PCR from week 36 to week 48 on respiratory samples sent to the diagnostic laboratory by the paediatric hospital (n = 2121). Retrospective analysis of the obtained data, using 2 x 2 contingency tables with Fisher's exact test, revealed evidence of an inverse relationship between HRV and H1N1 detection. Between weeks 36 and 48 of 2009, both HRV and H1N1 were detected but in different time frames. HRV dispersed widely during early September, peaking at the end of the month, whereas the H1N1 epidemic began during mid-October and was still active at the end of this survey. During the co-circulation period of these two respiratory viruses (weeks 43-46), HRV detection appeared to reduce the likelihood of H1N1 detection in the same sample (OR = 0.08-0.24 p <0.0001). These results support the hypothesis that HRV infections can reduce the probability of A(H1N1) infection. This viral interference between respiratory viruses could have affected the spread of the H1N1 viruses and delayed the influenza pandemic at the beginning of autumn in France.

[Comparison of three dosimetric techniques for lung tumor irradiation]. / Analyse des contraintes dosimétriques obtenues par trois techniques d'irradiation de tumeurs pulmonaires.

PURPOSE: Comparison of three dosimetric techniques of lung tumor delineation to integrate tumor motion during breathing. PATIENTS AND METHODS: Nineteen patients with T1-3N0M0 malignant lung tumor were treated with definitive chemoradiotherapy (14 cases) or pre-surgery chemoradiation. Doses were, respectively, 66 and 46Gy. CT-scan for delineation was performed during three phases of breathing: free breathing and deep breath-hold inspiration and expiration. GTV (gross tumor volume) was delineated on the three sequences. The classic technique included GTV from the free-breathing sequence plus a CTV (clinical target volume) margin of 5 to 8mm plus a PTV (planning target volume) margin of 7 to 10mm (including ITV [internal target volume] margin and set-up margin). The gating-like technique included GTV from the deep breath-hold inspiration sequence plus a CTV margin of 5 to 8mm plus a PTV margin of 2mm. The three-volume technique, included GTV as a result of the fusion of GTVs from the three sequences plus a CTV margin of 5 to 8mm plus a PTV margin of 2mm. Dosimetry was calculated for the three PTVs, if possible, with the same fields number and position. Dose constraints and rules were imposed to accept dosimetries: firstly spinal cord maximal dose less than 45Gy, followed by V95 % for PTV greater than or equal to 95 %, and V20 GY(Gy) for lung less than or equal to 30 %, V30 GY(Gy) for lung less than or equal to 20 %. RESULTS: GTVs were not statistically different between the three methods of delineation. PTVs were significantly lower with the gating-like technique. V95% of the PTV were not different between the three techniques. With the classic-, the gating-like- and the 3-volume techniques, dosimetry was considered as acceptable, respectively in 15, 18 and 15 cases. Comparisons of constraint values showed that the gating-like method gave the best results. In the case of pre-operative management, the gating-like method allowed the best results even for the V95% values. However, in the absence of gating device or without the possibility to use it, the 3-volume method allowed to take into account more precisely the organ motion than the classical technique. CONCLUSION: The 3-volume method can be done. It is a good method to take into account the organ motions. However, the gating-like method gives the best results leading to propose its use even for pre-operative patients with upper tumors.

Pandemic A(H1N1)2009 influenza virus detection by real time RT-PCR: is viral quantification useful?

The emergence of the influenza A(H1N1) 2009 virus prompted the development of sensitive RT-PCR detection methods. Most are real time RT-PCRs which can provide viral quantification. In this manuscript, we describe a universal influenza A RT-PCR targeting the matrix (M) gene, combined with an RNaseP RT-PCR. These PCRs allow the detection of all influenza A virus subtypes, including A(H1N1)2009, together with a real-time assessment of the quality of the specimens tested. These PCR procedures were evaluated on 209 samples collected from paediatric patients. Viral loads determined through Ct values were corrected according to the RNaseP Ct value. The mean viral load in the collected samples was estimated to be 6.84 log RNA copies/mL. For poor quality samples (RNaseP Ct > 27), corrections resulted in +3 to +8 Ct values for the M gene RT-PCR. Corrected influenza Ct values were lower in late samples. No correlation was established between viral loads and clinical severity or duration of disease.This study shows that real time RT-PCR targeting the matrix gene is a reliable tool for quantification of type A influenza virus but emphasises the need for sample quality control assessment through cellular gene quantification for reliable estimation of the viral load. This method would be useful for disease management when repeated specimens are collected from an infected individual.

[Sensitivity and specificity of the VIKIA Rota-Adeno immuno-chromatographic test (bioMérieux) and the ELISA IDEIA Rotavirus kit (Dako) compared to genotyping]. / Sensibilité et spécificité du test immuno-chromatographique VIKIA Rota-Adéno (bioMérieux) et du kit Elisa IDEIA Rotavirus (Dako) par rapport aux techniques de génotypage.

The performances of two diagnostic tests for rotavirus infection in stool samples were evaluated during a prospective study in children of less than 36 months in child-care centers of Lyon from November 2004 to May 2005. The VIKIA Rota-Adeno immuno-chromatographic test (bioMérieux) and the ELISA IDEIA Rotavirus kit (Dako) were compared with a referral method, the genotyping. Fifty-seven stool samples were collected and analyzed by RT-PCR. The virus genome was detected in 29 samples. The most frequent genotypic combinations were G9P[8] with a prevalence of 75.9%. Sensitivity and specificity of the VIKIA Rota-Adeno test and the ELISA IDEIA Rotavirus kit were strictly comparable and very good: 96.6% (83.0; 99.9) and 96.4% (81.6; 99.9), respectively. The immuno-chromatographic technique were in concordance with the ELISA tests in 93.6% of cases. Thus, the VIKIA Rota-Adeno test is a good alternative for the occasional analysis of stool samples in ambulatory practice.

Cold oxygen plasma technology efficiency against different airborne respiratory viruses.

BACKGROUND: Respiratory infections caused by viruses are major causes of upper and lower respiratory tract infections. They account for an important mortality and morbidity worldwide. Amongst these viruses, influenza viruses and paramyxoviruses are major pathogens. Their transmission is mainly airborne, by direct transmission through droplets from infected cases. OBJECTIVES: In the context of an influenza pandemic, as well as for the reduction of nosocomial infections, systems that can reduce or control virus transmission will reduce the burden of this disease. It may also be part of the strategy for pandemic mitigation. STUDY DESIGN: A new system based on physical decontamination of surface and air has been developed. This process generates cold oxygen plasma (COP) by subjecting air to high-energy deep-UV light. To test its efficiency, we have developed an experimental device to assess for the decontamination of nebulized respiratory viruses. High titer suspensions of influenza virus type A, human parainfluenza virus type 3 and RSV have been tested. RESULTS: Different experimental conditions have been evaluated against these viruses. The use of COP with an internal device allowed the best results against all viruses tested. We recorded a reduction of 6.5, 3.8 and 4 log(10) TCID50/mL of the titre of the hPIV-3, RSV and influenza virus A (H5N2) suspensions. CONCLUSIONS: The COP technology is an efficient and innovative strategy to control airborne virus dissemination. It could successfully control nosocomial diffusion of respiratory viruses in hospital setting, and could be useful for the reduction of influenza transmission in the various consultation settings implemented for the management of cases during a pandemic.