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1.
Vaccines (Basel) ; 12(6)2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38932394

ABSTRACT

Enhancing our comprehension of mRNA vaccines may facilitate the future design of novel vaccines aimed at augmenting immune protection while minimising reactogenic responses. Before this design is carried out, it is important to determine whether adaptive immunity correlates with the reactogenicity profile of vaccines. We studied a large cohort that was vaccinated with mRNA vaccines to answer this question. This was an observational study with real-world data. Reactogenicity data were obtained from the VigilVacCOVID study. Immunogenicity (humoral and cellular) data were retrieved from health records. One main population (n = 215) and two subpopulations were defined (subpopulation 1, n = 3563; subpopulation 2, n = 597). Sensitivity analyses were performed with subpopulations 1 and 2 to explore the consistency of results. We analysed the association of the intensity and types of adverse reactions with the development and quantity of elicited antibody titres. As an exploratory analysis in subpopulation 1, we assessed the association between reactogenicity and cellular immunogenicity. A higher incidence of fever, malaise, and myalgia including severe cases was significantly associated with the development and quantity of positive antibody titres. No significant findings were observed with cellular immunity. We observed a positive association between immunogenicity and reactogenicity. These findings can be relevant for the future development of our understanding of how mRNA vaccines function.

2.
J Infect Dis ; 226(9): 1528-1536, 2022 11 01.
Article in English | MEDLINE | ID: mdl-35993155

ABSTRACT

BACKGROUND: This study describes the genotypic and phenotypic characterization of novel human cytomegalovirus (HCMV) genetic variants of a cohort of 94 clinically resistant HCMV patients. METHODS AND RESULTS: Antiviral-resistant mutations were detected in the UL97, UL54, and UL56 target genes of 25 of 94 (26.6%) patients. The genotype-phenotype correlation study resolved the status of 5 uncharacterized UL54 deoxyribonucleic acid polymerase (G441S, A543V, F460S, R512C, A928T) and 2 UL56 terminase (F345L, P800L) mutations found in clinical isolates. A928T conferred high, triple resistance to ganciclovir, foscarnet, and cidofovir, and A543V had 10-fold reduced susceptibility to cidofovir. Viral growth assays showed G441S, A543V, F345L, and P800L impaired viral growth capacities compared with wild-type AD169 HCMV. Three-dimensional modeling predicted A543V and A928T phenotypes but not R512C, reinforcing the need for individual characterization of mutations by recombinant phenotyping. CONCLUSIONS: Extending mutation databases is crucial to optimize treatments and to improve the assessment of patients with resistant/refractory HCMV infection.


Subject(s)
Cytomegalovirus Infections , DNA-Directed DNA Polymerase , Humans , Cidofovir/therapeutic use , DNA-Directed DNA Polymerase/genetics , Viral Proteins/genetics , Drug Resistance, Viral/genetics , Ganciclovir/therapeutic use , Cytomegalovirus/genetics , Antiviral Agents/therapeutic use , Phenotype , Mutation
3.
Microbiol Spectr ; 10(2): e0019122, 2022 04 27.
Article in English | MEDLINE | ID: mdl-35343771

ABSTRACT

De novo mutations in the UL56 terminase subunit and its associated phenotypes were studied in the context of cytomegalovirus (CMV) transplant recipients clinically resistant to DNA-polymerase inhibitors, naive to letermovir. R246C was the only UL56 variant detected by standard and deep sequencing, located within the letermovir-resistance-associated region (residues 230-370). R246C emerged in 2/80 transplant recipients (1 hematopoietic and 1 heart) since first cytomegalovirus replication and responded transiently to various alternative antiviral treatments in vivo. Recombinant phenotyping showed R246C conferred an advanced viral fitness and was sensitive to ganciclovir, cidofovir, foscarnet, maribavir, and letermovir. These results demonstrate a low rate (2.5%) of natural occurring polymorphisms within the letermovir-resistant-associated region before its administration. Identification of high replicative capacity variants in patients not responding to treatment or experiencing relapses could be helpful to guide further therapy and dosing of antiviral molecules. IMPORTANCE We provide comprehensive data on the clinical correlates of both CMV genotypic follow-up by standard and deep sequencing and the clinical outcomes, as well as recombinant phenotypic results of this novel mutation. Our study emphasizes that the clinical follow-up in combination with genotypic and phenotypic studies is essential for the assessment and optimization of patients experiencing HCMV relapses or not responding to antiviral therapy. This information may be important for other researchers and clinicians working in the field to improve the care of transplant patients since drug-resistant CMV infections are an important emerging problem even with the new antiviral development.


Subject(s)
Cytomegalovirus Infections , Cytomegalovirus , Acetates , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Cytomegalovirus/genetics , Cytomegalovirus Infections/drug therapy , Drug Resistance, Viral/genetics , Humans , Mutation , Quinazolines , Recurrence , Transplant Recipients
4.
Infect Dis Ther ; 11(1): 587-593, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34762246

ABSTRACT

The immense impact of the COVID-19 pandemic on health systems has motivated the scientific community to search for clinical prognostic factors for SARS-CoV-2 infection. Low cycle threshold values (Ct) of diagnostic real-time RT-PCR assays in hospitalized patients have been associated with a poor prognosis in several studies, whereas other studies did not find this association. We explored whether SARS-CoV-2 Ct values at diagnosis were associated with a poor outcome (admission to hospital and death) in 604 community patients diagnosed at primary health centers. Although lower Ct values were found in patients who died of COVID-19, the Ct value was not significantly associated with a worse outcome in a multivariate analysis, while age remained an independent prognostic factor. We did not find evidence to support the role of Ct values as a prognostic factor of COVID-19 in community cases.

5.
J Infect Dis ; 224(8): 1325-1332, 2021 Oct 28.
Article in English | MEDLINE | ID: mdl-34329473

ABSTRACT

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse-transcription polymerase chain reaction (RT-PCR) provides a highly variable cycle threshold (Ct) value that cannot distinguish viral infectivity. Subgenomic ribonucleic acid (sgRNA) has been used to monitor active replication. Given the importance of long RT-PCR positivity and the need for work reincorporation and discontinuing isolation, we studied the functionality of normalized viral loads (NVLs) for patient monitoring and sgRNA for viral infectivity detection. METHODS: The NVLs measured through the Nucleocapsid and RNA-dependent-RNA-polymerase genes and sgRNA RT-PCRs were performed in 2 consecutive swabs from 84 healthcare workers. RESULTS: The NVLs provided similar and accurate quantities of both genes of SARS-CoV-2 at 2 different timepoints of infection, overcoming Ct-value and swab collection variability. Among SARS-CoV-2-positive samples, 51.19% were sgRNA-positive in the 1st RT-PCR and 5.95% in the 2nd RT-PCR. All sgRNA-positive samples had >4 log10 RNA copies/1000 cells, whereas samples with ≤1 log10 NVLs were sgRNA-negative. Although NVLs were positive until 29 days after symptom onset, 84.1% of sgRNA-positive samples were from the first 7 days, which correlated with viral culture viability. Multivariate analyses showed that sgRNA, NVLs, and days of symptoms were significantly associated (P < .001). CONCLUSIONS: The NVLs and sgRNA are 2 rapid accessible techniques that could be easily implemented in routine hospital practice providing a useful proxy for viral infectivity and coronavirus disease 2019 patient follow-up.


Subject(s)
COVID-19/diagnosis , SARS-CoV-2/isolation & purification , Viral Load/standards , Adult , Aftercare/standards , COVID-19/therapy , COVID-19/transmission , COVID-19/virology , COVID-19 Nucleic Acid Testing/statistics & numerical data , Clinical Decision-Making/methods , Epidemiological Monitoring , Female , Health Personnel/statistics & numerical data , Humans , Male , Middle Aged , Nasopharynx/pathology , Nasopharynx/virology , RNA, Viral/isolation & purification , SARS-CoV-2/genetics , SARS-CoV-2/pathogenicity
6.
Med. clín (Ed. impr.) ; 154(11): 433-439, jun. 2020. tab
Article in Spanish | IBECS | ID: ibc-195535

ABSTRACT

INTRODUCCIÓN: El citomegalovirus (CMV) es el patógeno oportunista más importante asociado al trasplante. El objetivo de este trabajo fue la caracterización de mutaciones de resistencia de CMV en pacientes receptores de trasplante alogénico de progenitores hematopoyéticos (alo-TPH) y el estudio de factores asociados. MÉTODOS: Se llevó a cabo un estudio retrospectivo de una cohorte de pacientes receptores de alo-TPH con reactivaciones postrasplante de CMV con cargas virales (CV) estables o en aumento, a pesar de un adecuado tratamiento antiviral al menos durante 2semanas. Se realizó el estudio de mutaciones de resistencia de los genes UL97 y UL54 mediante secuenciación Sanger. RESULTADOS: La infección refractaria de CMV de nuestro grupo de pacientes alo-TPH se correspondió con una tasa de infección por virus resistente del 21,43% (3 de 14 pacientes). Todos los pacientes con mutaciones de resistencia presentaron múltiples episodios de reactivación (p-valor 0,01). Las mutaciones encontradas fueron A594V y H520Q en el gen UL97 que confieren resistencia de alto grado a ganciclovir (GCV). Uno de los 3 casos con resistencia antiviral, se documentó con una CV baja (< 1.000 copias/ml) y tras corto tratamiento acumulado de GCV (41 días). CONCLUSIÓN: La mayor parte de los fracasos en el tratamiento del CMV se debió posiblemente a resistencia clínica; la falta de respuesta satisfactoria al tratamiento antiviral no siempre se acompaña de resistencia virológica. No obstante, la aparición de resistencias puede ocurrir de forma temprana tras el inicio del tratamiento anticipado y con CV por debajo de 1.000 copias/ml. El número de episodios de reactivación fue mayor entre los pacientes que se demostró resistencia virológica frente a los que no


INTRODUCTION: Cytomegalovirus (CMV) is the most important opportunistic pathogen associated with transplant. The objective of this study was the characterization of CMV resistance mutations in allogeneic haematopoietic cell transplant recipients (allo-TPH) and the study of associated factors. METHODS: A retrospective study of a cohort of allo-TPH recipients with post-transplant CMV reactivations with stable or increasing viral loads (CV), despite adequate antiviral treatment for at least 2weeks. The study of resistance mutations of the UL97 and UL54 genes was carried out by Sanger sequencing. RESULTS: Refractory CMV infection in our group of allo-TPH patients corresponded with a 21.43% rate of resistant virus infection (3 of 14 patients). All patients with resistance mutations had multiple reactivation episodes (P-value .01). The mutations found were A594V and H520Q in the UL97 gene that confers high-grade resistance to ganciclovir (GCV). One of the 3 cases with antiviral resistance was documented with a low VL (< 1000 copies/ml) and short accumulated GCV treatment (41 days). CONCLUSION: Most of the failures in the treatment of CMV were possibly due to clinical resistance; the lack of satisfactory response to antiviral treatment is not always accompanied by virological resistance. However, the appearance of resistances can occur early after the start of the treatment and with VL below 1000 copies / ml. The number of episodes of reactivation was higher among patients with virological resistance than those who did not


Subject(s)
Humans , Male , Female , Young Adult , Adult , Middle Aged , Cytomegalovirus Infections/drug therapy , Antiviral Agents/administration & dosage , Drug Resistance, Viral , Transplantation, Homologous/methods , Cytomegalovirus/drug effects , Hematopoietic Stem Cell Transplantation , Cytomegalovirus Infections/virology , Cytomegalovirus/genetics , Retrospective Studies , Acyclovir/administration & dosage , Cytomegalovirus Infections/etiology , Valacyclovir/administration & dosage
7.
Med Clin (Barc) ; 154(11): 433-439, 2020 06 12.
Article in English, Spanish | MEDLINE | ID: mdl-31785805

ABSTRACT

INTRODUCTION: Cytomegalovirus (CMV) is the most important opportunistic pathogen associated with transplant. The objective of this study was the characterization of CMV resistance mutations in allogeneic haematopoietic cell transplant recipients (allo-TPH) and the study of associated factors. METHODS: A retrospective study of a cohort of allo-TPH recipients with post-transplant CMV reactivations with stable or increasing viral loads (CV), despite adequate antiviral treatment for at least 2weeks. The study of resistance mutations of the UL97 and UL54 genes was carried out by Sanger sequencing. RESULTS: Refractory CMV infection in our group of allo-TPH patients corresponded with a 21.43% rate of resistant virus infection (3 of 14 patients). All patients with resistance mutations had multiple reactivation episodes (P-value .01). The mutations found were A594V and H520Q in the UL97 gene that confers high-grade resistance to ganciclovir (GCV). One of the 3 cases with antiviral resistance was documented with a low VL (< 1000 copies/ml) and short accumulated GCV treatment (41 days). CONCLUSION: Most of the failures in the treatment of CMV were possibly due to clinical resistance; the lack of satisfactory response to antiviral treatment is not always accompanied by virological resistance. However, the appearance of resistances can occur early after the start of the treatment and with VL below 1000 copies / ml. The number of episodes of reactivation was higher among patients with virological resistance than those who did not.


Subject(s)
Cytomegalovirus , Hematopoietic Stem Cell Transplantation , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Cytomegalovirus/genetics , Drug Resistance, Viral/genetics , Ganciclovir/therapeutic use , Humans , Mutation , Retrospective Studies , Transplant Recipients
8.
Int J Infect Dis ; 88: 73-79, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31401201

ABSTRACT

BACKGROUND: Severe cases of primary HIV infection have been described in patients presenting with neurological involvement, AIDS defining events or other life-threatening events. These severe forms have not been fully studied. OBJECTIVES: To determine the prevalence and characteristics of severe PHI in a hospital-based cohort of primary HIV infection, and the response to the early initiation of antiretroviral therapy (ART) at 12 months. METHODS: Every patient with PHI attending Hospital Clínic of Barcelona (1997-2015) was evaluated. Severe PHI was defined using clinical, analytical and immunological criteria. Chi-squared test was used for categorical variables and Student's t-test for quantitative variables. RESULTS: 33% of 224 PHI patients (95% CI: 26.84%-39.16%) had a severe PHI. These patients had more symptoms, abnormal analytical parameters and hospital admissions. The severe PHI group had a significantly higher viral load although no differences were observed at 12 months in terms of viral suppression or CD4 count recovery. None died during PHI. CONCLUSIONS: Up to one third of patients in our cohort presented with a severe PHI, which was associated with higher hospitalization rates and higher plasma HIV RNA viral load. However, severe forms were not associated to a worse clinical, immunological or virological outcome at 12 months.


Subject(s)
HIV Infections/drug therapy , Adult , Anti-HIV Agents/therapeutic use , CD4 Lymphocyte Count , Female , HIV Infections/epidemiology , HIV Infections/immunology , HIV Infections/virology , HIV-1/isolation & purification , HIV-1/physiology , Hospitals/statistics & numerical data , Humans , Male , Middle Aged , Prospective Studies , Spain/epidemiology , Viral Load
9.
PLoS One ; 14(7): e0219701, 2019.
Article in English | MEDLINE | ID: mdl-31318908

ABSTRACT

OBJETIVES: The aim of this study was to identify CMV drug resistance mutations (DRM) in solid organ transplant (SOT) recipients with suspected resistance comparing next-generation sequencing (NGS) with Sanger sequencing and assessing risk factors and the clinical impact of resistance. METHODS: Using Sanger sequencing as the reference method, we prospectively assessed the ability of NGS to detect CMV DRM in the UL97 and UL54 genes in a nationwide observational study from September 2013 to August 2016. RESULTS: Among 44 patients recruited, 14 DRM were detected by Sanger in 12 patients (27%) and 20 DRM were detected by NGS, in 16 (36%). NGS confirmed all the DRM detected by Sanger. The additional six mutations detected by NGS were present in <20% of the sequenced population, being located in the UL97 gene and conferring high-level resistance to ganciclovir. The presence of DRM by NGS was associated with lung transplantation (p = 0.050), the administration of prophylaxis (p = 0.039), a higher mean time between transplantation and suspicion of resistance (p = 0.038) and longer antiviral treatment duration before suspicion (p = 0.024). However, the latter was the only factor independently associated with the presence of DRM by NGS in the multivariate analysis (OR 2.24, 95% CI 1.03 to 4.87). CONCLUSIONS: NGS showed a higher yield than Sanger sequencing for detecting CMV resistance mutations in SOT recipients. The presence of DRM detected by NGS was independently associated with longer antiviral treatment.


Subject(s)
Cytomegalovirus/genetics , Cytomegalovirus/isolation & purification , Drug Resistance, Viral/genetics , High-Throughput Nucleotide Sequencing/methods , Mutation/genetics , Transplant Recipients , Female , Genes, Viral , Humans , Male , Middle Aged
10.
AIDS ; 33(10): 1613-1617, 2019 08 01.
Article in English | MEDLINE | ID: mdl-31090546

ABSTRACT

OBJECTIVES: Integrase strand-transfer inhibitor (InSTI)-based regimens are the preferred combinations for naïve HIV-infected individuals. Polymorphic substitutions that reduce InSTIs activity have been described, with E157Q being one of the most frequently found. This study aimed to evaluate the prevalence of E157Q substitution in newly diagnosed acute/recent HIV cases and the presence of transmission clusters. DESIGN: Prospective cohort study in patients with acute/recent HIV infection. METHODS: Genotypic drug resistance tests were performed in all consecutive patients prospectively enrolled with a documented infection of less than 6 months from May 2015 to May 2017. Sequences were obtained by ultra-deep sequencing. Phylogenetic inferences were performed using maximum likelihood trees constructed with Mega 6.06. Bootstrap values of 75% or greater were defined for cluster assignment. Follow-up was, at least, 1 year. RESULTS: In six out of 67 consecutive patients (8.95%, 95% confidence interval 4.17-18.19) with acute/recent HIV infection, strains carrying the E157Q InSTI substitution were detected. All cases were MSM patients infected with subtype B strains. No other resistance substitutions were detected in these cases. Median viral load was 5.33 (interquartile range: 4.54-5.71) log10 copies/ml and, in all cases, the mutational viral load was high (>95%). Three cases were included in transmission clusters. Three cases responded to dolutegravir-based regimens; nonnucleoside reverse transcriptase inhibitor-based regimens were used for the other case(s). CONCLUSION: E157Q substitution, reducing raltegravir and elvitegravir activity, was frequently found in acute/recent HIV cases. All cases were infected with subtype B, and some were included in clusters. Cases treated with dolutegravir-based regimens had good virological response.


Subject(s)
Drug Resistance, Viral , HIV Infections/virology , HIV Integrase Inhibitors/pharmacology , HIV Integrase/genetics , HIV/drug effects , HIV/enzymology , Mutation, Missense , Adult , Amino Acid Substitution , Disease Transmission, Infectious , Female , Gene Frequency , Genotype , Genotyping Techniques , HIV Infections/transmission , High-Throughput Nucleotide Sequencing , Humans , Male , Molecular Epidemiology , Phylogeny , Prevalence , Prospective Studies , Quinolones/pharmacology , Raltegravir Potassium/pharmacology , Sexual and Gender Minorities , Viral Load
11.
PLoS One ; 13(7): e0199975, 2018.
Article in English | MEDLINE | ID: mdl-30011283

ABSTRACT

In recent decades, vaccination has substantially reduced the number of measles cases to levels close to the elimination stage. However, major measles outbreaks occurred in Europe during 2010-2012, after the introduction of the D4-Enfield lineage. We have performed a molecular characterization of 75 measles virus genotype D4 strains from patients infected in Spain between 2004 and 2012 by sequencing the N-450 region and the M-F non-coding region (M-F NCR) in order to identify genetic features of these viruses. The analysis of the N-450 region confirmed that all samples obtained since 2008 belonged to variants or sets of identical sequences of the D4-Enfield lineage, including a new one named MVs/Madrid.ESP/46.10/. Analysis of the M-F NCR showed insertions and deletions associated with previously described, uncommon non-standard genome length measles viruses. This genetic feature was identified in the D4-Enfield lineage viruses, but not in the other D4 viruses that were circulating in Spain before 2008, suggesting that these non-standard length M-F NCR sequences are characteristic of the D4-Enfield lineage. The results of the phylogenetic analysis of Spanish M-F NCRs suggest higher resolution in discriminating strains than did the N-450 analysis. In addition, the results of the analysis of the M-F NCR on the MVs/Madrid.ESP/46.10/ sub-lineage seem to support the potential utility of this region as a tool for epidemiological surveillance complementary to the N-450 region, as previously suggested. Further investigation on this question, as well as the surveillance of new potentially emerging strains with non-standard length M-F NCR are strongly recommended as part of future strategies for measles elimination.


Subject(s)
Disease Outbreaks , Genotype , Measles virus/genetics , Measles virus/physiology , Measles/epidemiology , Humans , Measles virus/classification , Phylogeny , Spain/epidemiology
12.
J Antimicrob Chemother ; 72(3): 829-836, 2017 03 01.
Article in English | MEDLINE | ID: mdl-27999018

ABSTRACT

Background: Initiating ART during acute/recent HIV-1 infection reduces viral reservoir formation. It has been proposed that, during this phase, the size of the viral reservoir could be further reduced by the association of immunomodulatory therapy with ART. Contradictory results have emerged, however, from two trials evaluating the impact on immune recovery and the viral reservoir of adding cyclosporine A to ART during primary HIV-1 infection. Patients and methods: Twenty patients with acute/recent HIV-1 infection were randomized to receive ART alone (tenofovir, emtricitabine and lopinavir/ritonavir) or associated with 8 weeks of cyclosporine A (0.3-0.6 mg/kg twice daily). The impact on viral load, immune response and integrated and non-integrated DNA viral reservoir at 0, 8 and 36 weeks of treatment was evaluated. Results: The estimated median time from HIV-1 infection to ART onset was 63 days (IQR 53; 79.5) with 90% of patients at Fiebig V stage. No significant differences were observed in viral load decay, CD4 T cell recovery, immune response markers or the evolution of integrated DNA at week 8 (end of cyclosporine A) and week 36 between groups. However, non-integrated DNA significantly increased in the cyclosporine A arm between weeks 0 and 36. Cyclosporine A was well tolerated. Conclusions: Adding cyclosporine A to ART during acute/recent infection did not improve immune recovery. However, unintegrated DNA increased in the cyclosporine A group, suggesting an anti-integration effect, a point warranting further research (ClinicalTrials.gov Identifier: NCT00979706).


Subject(s)
Anti-HIV Agents/administration & dosage , Antiretroviral Therapy, Highly Active , Cyclosporine/administration & dosage , HIV Infections/drug therapy , HIV-1/drug effects , Acute Disease , Adult , Anti-HIV Agents/adverse effects , Anti-HIV Agents/therapeutic use , Cyclosporine/adverse effects , Cyclosporine/therapeutic use , Drug Therapy, Combination , Female , HIV Infections/virology , HIV Protease Inhibitors/administration & dosage , HIV Protease Inhibitors/adverse effects , HIV Protease Inhibitors/therapeutic use , Humans , Lopinavir/administration & dosage , Lopinavir/therapeutic use , Male , Middle Aged , Pilot Projects , Ritonavir/administration & dosage , Ritonavir/therapeutic use , Young Adult
13.
BMC Infect Dis ; 15: 44, 2015 Feb 06.
Article in English | MEDLINE | ID: mdl-25656393

ABSTRACT

BACKGROUND: Influenza virus infections are responsible for significant morbidity and mortality in both pediatric and adult populations worldwide. Rapid and accurate diagnosis of influenza is necessary for appropriate patient management during the influenza season and for optimal utilization of anti-influenza therapy. We prospectively tested the accuracy of a simple and rapid diagnostic method. METHODS: Ninety-eight samples (nasal and pharyngeal swabs) from patients with upper respiratory tract infection symptoms who presented to primary healthcare centres in Barcelona (Spain) were prospectively analyzed. The samples were collected as part of influenza surveillance program. Samples that had enough volume to make the new test after aliquoting the amount needed to perform routine tests were included. None of the samples were pre-selected as a result of their status in relation to influenza virus. Samples were analyzed by in-house real-time PCR and Alere i Influenza A & B (Alere i), which uses isothermal amplification of nucleic acids for the qualitative detection of influenza A and B in nasal swabs transported in viral transport media. The two techniques were compared by positive percent agreement (PPA) and negative percent agreement (NPA). Statistical analysis was performed with Stata. RESULTS: Of the 98 samples analysed 90 were concordant; 46 (46.9%) were positive and 44 (44.9%) were negative. Five samples showed invalid results with the Alere i test and could be not re-tested due to insufficient sample volume and were not included in the final statistical analysis. In the 93 remaining samples, the Alere i test showed 97% of accuracy having correctly classified 90 samples. We obtained discordant results in 3 samples (3%). The PPA was 93.8% for influenza A and 94.1% for influenza B, and NPA was 100% for influenza A and influenza B virus. In addition, the Alere i was very rapid (15 minutes or less) and extremely easy to use. CONCLUSIONS: The Alere i test provided a good correlation compared to the real-time PCR test for the diagnosis of influenza. Since this method can be performed in minutes, it allows immediate, accurate clinical decisions to prescribe appropriate antiviral treatment or isolation of patients.


Subject(s)
Influenza A virus/isolation & purification , Influenza B virus/isolation & purification , Influenza, Human/diagnosis , Nucleic Acid Amplification Techniques/methods , Adult , Child , Humans , Influenza A virus/genetics , Influenza B virus/genetics , Influenza, Human/epidemiology , Influenza, Human/virology , Nose/virology , Pharynx/virology , RNA, Viral/genetics , RNA, Viral/isolation & purification , Real-Time Polymerase Chain Reaction , Sensitivity and Specificity , Spain/epidemiology , Time Factors
14.
J Gen Virol ; 90(Pt 11): 2739-2745, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19625457

ABSTRACT

The linear haemagglutinin noose epitope (HNE; aa 379-410) is a protective B-cell epitope and considered to be highly conserved in both the vaccine and the wild-type measles virus (MeV) haemagglutinin (H) proteins. Vaccine virus-derived monoclonal antibodies (mAbs) BH6 and BH216, which target the HNE, neutralized MeVs of genotypes B3, C2, D4, D5, D6, D7 and D8, and the vaccine strain Edmonston Zagreb. In the case of genotype H1, only strain Berlin.DEU/44.01 was neutralized by these mAbs, whereas strains Shenyang.CHN/22.99 and Sofia.BGR/19.05 were not. The H gene sequences of these two strains showed an exchange of proline 397 (P397) to leucine (L397). Mutated H proteins, with P397 exchanged to L and vice versa, were compared with original H proteins by indirect fluorescence assay. H proteins exhibiting P397 but not those with L397 were recognized by BH6 and BH216. This indicates that L397 leads to the loss of the neutralizing HNE. In contrast, human sera obtained from vaccinees (n=10) did not discriminate between genotype H1 variants P397 and L397. This concurs with the epidemiological observation that the live-attenuated vaccine protects against both H1 variants. Furthermore, we demonstrated that MeVs of genotype H1 also lack the neutralizing epitopes defined by the vaccine virus-induced mAbs BH15, BH125 and BH47. The loss of several neutralizing epitopes, as shown for H1 viruses currently circulating endemically in Asia, implies that epitope monitoring should be considered to be included in measles surveillance.


Subject(s)
Antibodies, Viral/immunology , Epitopes/immunology , Hemagglutinins, Viral/immunology , Measles Vaccine/immunology , Measles virus/immunology , Amino Acid Sequence , Asia , Genotype , Hemagglutinins, Viral/genetics , Humans , Measles/virology , Measles virus/genetics , Measles virus/isolation & purification , Molecular Sequence Data , Mutant Proteins/immunology , Mutation, Missense , Neutralization Tests , RNA, Viral/genetics , Sequence Analysis, DNA
15.
J Med Virol ; 75(1): 137-46, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15543577

ABSTRACT

Molecular characterization of measles virus is important for disease surveillance and for monitoring elimination of the virus throughout the world. Furthermore, knowledge of genotype distribution in as many countries as possible, is useful for tracing the origin of a strain, especially in countries without endemic measles disease, where most cases are imported. Data on genotypes circulating in Spain from 1970 to 1997 showed the prevalence of genotypes C1, C2, and D6, with subsequent replacement of each other. After the establishment of the Spanish Measles Elimination Plan, genotyping with a new retrotranscriptase polymerase chain reaction (RT-PCR) was undertaken directly on 92 specimens, corresponding to 90 patients, which were positive for measles by a different diagnostic RT-PCR. Genotypes B3, D4, D8, A, C2, H1, and D7 were found in different autonomous communities (Madrid, Balearic Islands, Valencia Community, Extremadura, Andalusia, Canary Islands and Murcia) between 2001 and 2003 with none of these genotypes being prevalent. After the introduction of the vaccine in 1978, the incidence of the disease decreased from 150,000 cases in 1977 to 64 in 2002. This could be the reason for the change observed in the pattern of measles genotype circulation, since this pattern was reported in countries at an advanced stage of eradication of measles. This report considers that Spain is on the way to eradicating measles.


Subject(s)
Measles virus/genetics , Measles/epidemiology , Molecular Epidemiology , Base Sequence , DNA, Complementary/chemistry , DNA, Complementary/metabolism , Genotype , Humans , Immunization Programs , Measles/prevention & control , Measles/virology , Measles Vaccine , Measles virus/isolation & purification , Molecular Sequence Data , Nucleocapsid Proteins , Nucleoproteins/genetics , Phylogeny , RNA, Viral/genetics , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, DNA , Sequence Homology , Spain/epidemiology , Viral Proteins/genetics
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