RESUMO
Large-scale vaccination campaigns have prevented countless hospitalizations and deaths due to COVID-19. However, the emergence of SARS-CoV-2 variants that escape from immunity challenges the effectiveness of current vaccines. Given this continuing evolution, an important question is when and how to update SARS-CoV-2 vaccines to antigenically match circulating variants, similarly to seasonal influenza viruses where antigenic drift necessitates periodic vaccine updates. Here, we studied SARS-CoV-2 antigenic drift by assessing neutralizing activity against variants of concern (VOCs) in a set of sera from patients infected with viral sequence-confirmed VOCs. Infections with D614G or Alpha strains induced the broadest immunity, whereas individuals infected with other VOCs had more strain-specific responses. Omicron BA.1 and BA.2 were substantially resistant to neutralization by sera elicited by all other variants. Antigenic cartography revealed that Omicron BA.1 and BA.2 were antigenically most distinct from D614G, associated with immune escape, and possibly will require vaccine updates to ensure vaccine effectiveness.
Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Neutralizantes , Anticorpos Antivirais , Antígenos Virais/genética , Vacinas contra COVID-19 , Humanos , SARS-CoV-2/genéticaRESUMO
Neutrophils are important players in COVID-19, contributing to tissue damage by release of inflammatory mediators, including ROS and neutrophil elastase. Longitudinal studies on the effects of COVID-19 on neutrophil phenotype and function are scarce. Here, we longitudinally investigated the phenotype and degranulation of neutrophils in COVID-19 patients (28 nonhospitalized and 35 hospitalized patients) compared with 17 healthy donors (HDs). We assessed phenotype, degranulation, CXCL8 (IL-8) release, and ROS generation within 8 days, at one or 6 month(s) after COVID-19 diagnosis. For degranulation and ROS production, we stimulated neutrophils, either with ssRNA and TNF or granulocyte-macrophage colony-stimulating factor and N-Formylmethionyl-leucyl-phenylalanine. During active COVID-19, neutrophils from hospitalized patients were more immature than from HDs and were impaired in degranulation and ROS generation, while neutrophils from nonhospitalized patients only demonstrated reduced CD66b+ granule release and ROS production. Baseline CD63 expression, indicative of primary granule release, and CXCL8 production by neutrophils from hospitalized patients were elevated for up to 6 months. These findings show that patients hospitalized due to COVID-19, but not nonhospitalized patients, demonstrated an aberrant neutrophil phenotype, degranulation, CXCL8 release, and ROS generation that partially persists up to 6 months after infection.
Assuntos
COVID-19 , Neutrófilos , Humanos , Neutrófilos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Teste para COVID-19 , COVID-19/metabolismo , ExocitoseRESUMO
BACKGROUND: Baloxavir marboxil (baloxavir) is a polymerase acidic protein (PA) endonuclease inhibitor with clinical efficacy in the treatment of uncomplicated influenza, including in outpatients at increased risk for complications. The postexposure prophylactic efficacy of baloxavir in the household setting is unclear. METHODS: We conducted a multicenter, double-blind, randomized, placebo-controlled trial to evaluate the postexposure prophylactic efficacy of baloxavir in household contacts of index patients with confirmed influenza during the 2018-2019 season in Japan. The participants were assigned in a 1:1 ratio to receive either a single dose of baloxavir or placebo. The primary end point was clinical influenza, as confirmed by reverse-transcriptase-polymerase-chain-reaction testing, over a period of 10 days. The occurrence of baloxavir-selected PA substitutions associated with reduced susceptibility was assessed. RESULTS: A total of 752 household contacts of 545 index patients were randomly assigned to receive baloxavir or placebo. Among the index patients, 95.6% had influenza A virus infection, 73.6% were younger than 12 years of age, and 52.7% received baloxavir. Among the participants who could be evaluated (374 in the baloxavir group and 375 in the placebo group), the percentage in whom clinical influenza developed was significantly lower in the baloxavir group than in the placebo group (1.9% vs. 13.6%) (adjusted risk ratio, 0.14; 95% confidence interval [CI], 0.06 to 0.30; P<0.001). Baloxavir was effective in high-risk, pediatric, and unvaccinated subgroups of participants. The risk of influenza infection, regardless of symptoms, was lower with baloxavir than with placebo (adjusted risk ratio, 0.43; 95% CI, 0.32 to 0.58). The incidence of adverse events was similar in the two groups (22.2% in the baloxavir group and 20.5% in the placebo group). In the baloxavir group, the viral PA substitutions I38T/M or E23K were detected in 10 (2.7%) and 5 (1.3%) participants, respectively. No transmission of these variants from baloxavir-treated index patients to participants in the placebo group was detected; however, several instances of transmission to participants in the baloxavir group could not be ruled out. CONCLUSIONS: Single-dose baloxavir showed significant postexposure prophylactic efficacy in preventing influenza in household contacts of patients with influenza. (Funded by Shionogi; Japan Primary Registries Network number, JapicCTI-184180.).
Assuntos
Antivirais/uso terapêutico , Transmissão de Doença Infecciosa/prevenção & controle , Vírus da Influenza A , Influenza Humana/prevenção & controle , Oxazinas/uso terapêutico , Piridinas/uso terapêutico , Tiepinas/uso terapêutico , Triazinas/uso terapêutico , Administração Oral , Adolescente , Adulto , Idoso , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Criança , Pré-Escolar , Dibenzotiepinas , Método Duplo-Cego , Endonucleases/antagonistas & inibidores , Família , Feminino , Humanos , Vírus da Influenza A/genética , Vírus da Influenza A/isolamento & purificação , Influenza Humana/transmissão , Influenza Humana/virologia , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Morfolinas , Oxazinas/administração & dosagem , Oxazinas/efeitos adversos , Piridinas/administração & dosagem , Piridinas/efeitos adversos , Piridonas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tiepinas/administração & dosagem , Tiepinas/efeitos adversos , Triazinas/administração & dosagem , Triazinas/efeitos adversosRESUMO
OBJECTIVES: To assess whether viral, bacterial, metabolic, and autoimmune diseases are missed by conventional diagnostics among children with severe acute encephalopathy in sub-Saharan Africa. STUDY DESIGN: One hundred thirty-four children (6 months to 18 years) presenting with nontraumatic coma or convulsive status epilepticus to 1 of 4 medical referral centers in Uganda, Malawi, and Rwanda were enrolled between 2015 and 2016. Locally available diagnostic tests could be supplemented in 117 patients by viral, bacterial, and 16s quantitative polymerase chain reaction testing, metagenomics, untargeted metabolomics, and autoimmune immunohistochemistry screening. RESULTS: Fourteen (12%) cases of viral encephalopathies, 8 (7%) cases of bacterial central nervous system (CNS) infections, and 4 (4%) cases of inherited metabolic disorders (IMDs) were newly identified by additional diagnostic testing as the most likely cause of encephalopathy. No confirmed cases of autoimmune encephalitis were found. Patients for whom additional diagnostic testing aided causal evaluation (aOR 3.59, 90% CI 1.57-8.36), patients with a viral CNS infection (aOR 7.91, 90% CI 2.49-30.07), and patients with an IMD (aOR 9.10, 90% CI 1.37-110.45) were at increased risk for poor outcome of disease. CONCLUSIONS: Viral and bacterial CNS infections and IMDs are prevalent causes of severe acute encephalopathy in children in Uganda, Malawi, and Rwanda that are missed by conventional diagnostics and are associated with poor outcome of disease. Improved diagnostic capacity may increase diagnostic yield and might improve outcome of disease.
Assuntos
Encefalopatias , Encefalite , Doenças Metabólicas , Criança , Humanos , Encefalopatias/diagnóstico , Encefalopatias/complicações , Encefalite/complicações , Encefalite/diagnóstico , Encefalite/epidemiologia , Estudos de Coortes , MalauiRESUMO
Pneumonia caused by multi-drug-resistant Klebsiella pneumoniae (MDR-Kpneu) poses a major public health threat, especially to immunocompromised or hospitalized patients. This study aimed to determine the immunostimulatory effect of the Toll-like receptor 5 ligand flagellin on primary human lung epithelial cells during infection with MDR-Kpneu. Human bronchial epithelial (HBE) cells, grown on an air-liquid interface, were inoculated with MDR-Kpneu on the apical side and treated during ongoing infection with antibiotics (meropenem) and/or flagellin on the basolateral and apical side, respectively; the antimicrobial and inflammatory effects of flagellin were determined in the presence or absence of meropenem. In the absence of meropenem, flagellin treatment of MDR-Kpneu-infected HBE cells increased the expression of antibacterial defense genes and the secretion of chemokines; moreover, supernatants of flagellin-exposed HBE cells activated blood neutrophils and monocytes. However, in the presence of meropenem, flagellin did not augment these responses compared to meropenem alone. Flagellin did not impact the outgrowth of MDR-Kpneu. Flagellin enhances antimicrobial gene expression and chemokine release by the MDR-Kpneu-infected primary human bronchial epithelium, which is associated with the release of mediators that activate neutrophils and monocytes. Topical flagellin therapy may have potential to boost immune responses in the lung during pneumonia.
Assuntos
Klebsiella , Pneumonia , Humanos , Flagelina/farmacologia , Meropeném/farmacologia , Células Epiteliais , Antibacterianos/farmacologiaRESUMO
BACKGROUND: Few robust longitudinal data on long-term coronavirus disease 2019 (COVID-19) symptoms are available. We evaluated symptom onset, severity and recovery across the full spectrum of disease severity, up to one year after illness onset. METHODS: The RECoVERED Study is a prospective cohort study based in Amsterdam, the Netherlands. Participants agedâ ≥18 years were enrolled following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) diagnosis via the local public health service and from hospitals. Standardized symptom questionnaires were completed at enrollment, 1 week and month later, and monthly thereafter. Clinical severity was defined according to World Health Organization (WHO) criteria. Kaplan-Meier methods were used to compare time from illness onset to symptom recovery, by clinical severity. We examined determinants of time to recovery using multivariable Cox proportional hazards models. RESULTS: Between 11 May 2020 and 1 May 2021, 342 COVID-19 patients (192 [56%] male) were enrolled, of whom 99/342 (29%) had mild, 145/342 (42%) moderate, 56/342 (16%) severe, and 42/342 (12%) critical disease. The proportion of participants who reported at least 1 persistent symptom at 12 weeks after illness onset was greater in those with severe/critical disease (86.7% [95% confidence interval {CI}â =â 76.5-92.7%]) compared to those with mild or moderate disease (30.7% [95% CIâ =â 21.1-40.9%] and 63.8% [95% CIâ =â 54.8-71.5%], respectively). At 12 months after illness onset, two-fifths of participants (40.7% [95% CIâ =â 34.2-7.1]) continued to reportâ ≥1 symptom. Recovery was slower in female compared to male participants (adjusted hazard ratio [aHR] 0.65 [95% CIâ =â .47-.92]) and those with a body mass index [BMI] â ≥30kg/m2 compared to BMIâ <25kg/m2 (hazard ratio [HR] 0.62 [95% CIâ =â .39-.97]). CONCLUSIONS: COVID-19 symptoms persisted for one year after illness onset, even in some individuals with mild disease. Female sex and obesity were the most important determinants of speed of recovery from symptoms.
Assuntos
COVID-19 , Adolescente , Adulto , COVID-19/diagnóstico , Feminino , Humanos , Masculino , Modelos de Riscos Proporcionais , Estudos Prospectivos , SARS-CoV-2 , Índice de Gravidade de DoençaRESUMO
We report a severe acute respiratory syndrome coronavirus 2 superspreading event in the Netherlands after distancing rules were lifted in nightclubs, despite requiring a negative test or vaccination. This occurrence illustrates the potential for rapid dissemination of variants in largely unvaccinated populations under such conditions. We detected subsequent community transmission of this strain.
Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , Genômica , Humanos , Países Baixos/epidemiologia , SARS-CoV-2/genéticaRESUMO
BACKGROUND: Emerging and future SARS-CoV-2 variants may jeopardize the effectiveness of vaccination campaigns. Therefore, it is important to know how the different vaccines perform against diverse SARS-CoV-2 variants. METHODS AND FINDINGS: In a prospective cohort of 165 SARS-CoV-2 naive health care workers in the Netherlands, vaccinated with either one of four vaccines (BNT162b2, mRNA-1273, AZD1222 or Ad26.COV2.S), we performed a head-to-head comparison of the ability of sera to recognize and neutralize SARS-CoV-2 variants of concern (VOCs; Alpha, Beta, Gamma, Delta and Omicron). Repeated serum sampling was performed 5 times during a year (from January 2021 till January 2022), including before and after booster vaccination with BNT162b2. Four weeks after completing the initial vaccination series, SARS-CoV-2 wild-type neutralizing antibody titers were highest in recipients of mRNA-1273, followed by recipients of BNT162b2 (geometric mean titers (GMT) of 358 [95% CI 231-556] and 214 [95% CI 153-299], respectively; p<0.05), and substantially lower in those vaccinated with the adenovirus vector-based vaccines AZD1222 and Ad26.COV2.S (GMT of 18 [95% CI 11-30] and 14 [95% CI 8-25] IU/ml, respectively; p<0.001). VOCs neutralization was reduced in all vaccine groups, with the greatest reduction in neutralization GMT observed against the Omicron variant (fold change 0.03 [95% CI 0.02-0.04], p<0.001). The booster BNT162b2 vaccination increased neutralizing antibody titers for all groups with substantial improvement against the VOCs including the Omicron variant. We used linear regression and linear mixed model analysis. All results were adjusted for possible confounding of age and sex. Study limitations include the lack of cellular immunity data. CONCLUSIONS: Overall, this study shows that the mRNA vaccines appear superior to adenovirus vector-based vaccines in inducing neutralizing antibodies against VOCs four weeks after initial vaccination and after booster vaccination, which implies the use of mRNA vaccines for both initial and booster vaccination.
Assuntos
COVID-19 , SARS-CoV-2 , Vacina de mRNA-1273 contra 2019-nCoV , Ad26COVS1 , Anticorpos Neutralizantes , Anticorpos Antivirais , Formação de Anticorpos , Vacina BNT162 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , ChAdOx1 nCoV-19 , Estudos de Coortes , Pessoal de Saúde , Humanos , Países Baixos/epidemiologia , Estudos Prospectivos , SARS-CoV-2/genéticaRESUMO
BACKGROUND: Currently, there is limited evidence about the long-term impact on physical, social and emotional functioning, i.e. health-related quality of life (HRQL) after mild or moderate COVID-19 not requiring hospitalization. We compared HRQL among persons with initial mild, moderate or severe/critical COVID-19 at 1 and 12 months following illness onset with Dutch population norms and investigated the impact of restrictive public health control measures on HRQL. METHODS: RECoVERED, a prospective cohort study in Amsterdam, the Netherlands, enrolled adult participants after confirmed SARS-CoV-2 diagnosis. HRQL was assessed with the Medical Outcomes Study Short Form 36-item health survey (SF-36). SF-36 scores were converted to standard scores based on an age- and sex-matched representative reference sample of the Dutch population. Differences in HRQL over time were compared among persons with initial mild, moderate or severe/critical COVID-19 using mixed linear models adjusted for potential confounders. RESULTS: By December 2021, 349 persons were enrolled of whom 269 completed at least one SF-36 form (77%). One month after illness onset, HRQL was significantly below population norms on all SF-36 domains except general health and bodily pain among persons with mild COVID-19. After 12 months, persons with mild COVID-19 had HRQL within population norms, whereas persons with moderate or severe/critical COVID-19 had HRQL below population norms on more than half of the SF-36 domains. Dutch-origin participants had significantly better HRQL than participants with a migration background. Participants with three or more COVID-19 high-risk comorbidities had worse HRQL than part participants with fewer comorbidities. Participants who completed the SF-36 when restrictive public health control measures applied reported less limitations in social and physical functioning and less impaired mental health than participants who completed the SF-36 when no restrictive measures applied. CONCLUSIONS: Twelve months after illness onset, persons with initial mild COVID-19 had HRQL within population norms, whereas persons with initial moderate or severe/critical COVID-19 still had impaired HRQL. Having a migration background and a higher number of COVID-19 high-risk comorbidities were associated with worse HRQL. Interestingly, HRQL was less impaired during periods when restrictive public health control measures were in place compared to periods without.
Assuntos
COVID-19 , Qualidade de Vida , Adulto , Humanos , Qualidade de Vida/psicologia , Estudos Prospectivos , COVID-19/epidemiologia , Teste para COVID-19 , SARS-CoV-2RESUMO
Early detection of bacterial transmission and outbreaks in hospitals is important because nosocomial infections can result in health complications and longer hospitalization. Current practice to detect outbreaks uses genotyping methods amplified fragment length polymorphism (AFLP) and whole genome sequencing (WGS), which are not suitable methods for real-time transmission screening of both susceptible and resistant bacteria. The aim was to assess the typing technique Fourier transform infrared (FTIR) spectroscopy as real-time screening method to discriminate large amounts of susceptible and resistant bacteria at strain level when there is no evident outbreak in comparison with the WGS reference. Isolates of past hospital outbreak strains of Acinetobacter baumannii/calcoaceticus complex (n = 25), Escherichia coli (n = 31), Enterococcus faecium (n = 22), Staphylococcus aureus (n = 37) and Pseudomonas aeruginosa (n = 30) were used for validation of FTIR. Subsequently, Enterococcus faecalis (n = 106) and Enterococcus faecium (n = 104) isolates from weekly routine screening samples when no potential outbreak was present were analysed. FTIR showed reproducibility and congruence of cluster composition with WGS for A. baumannii/calcoaceticus complex and E. faecium outbreak isolates. The FTIR results of E. faecalis and E. faecium isolates from routine samples showed reproducibility, but the congruence of cluster composition with WGS was low. For A. baumannii/calcoaceticus complex and E. faecium outbreak isolates, FTIR appears to be a discriminatory typing tool. However, our study shows the discriminatory power is too low to screen real-time for transmission of E. faecium and E. faecalis at patient wards based on isolates acquired in routine surveillance cultures when there is no clear suspicion of an ongoing outbreak.
Assuntos
Infecção Hospitalar , Enterococcus faecium , Infecções por Bactérias Gram-Positivas , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/genética , Infecção Hospitalar/microbiologia , Enterococcus faecium/genética , Genoma Bacteriano , Genótipo , Infecções por Bactérias Gram-Positivas/epidemiologia , Infecções por Bactérias Gram-Positivas/genética , Infecções por Bactérias Gram-Positivas/microbiologia , Hospitais , Humanos , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Sequenciamento Completo do Genoma/métodosRESUMO
BACKGROUND: Antivirals are infrequently prescribed in European primary care for influenza-like illness, mostly because of perceived ineffectiveness in real world primary care and because individuals who will especially benefit have not been identified in independent trials. We aimed to determine whether adding antiviral treatment to usual primary care for patients with influenza-like illness reduces time to recovery overall and in key subgroups. METHODS: We did an open-label, pragmatic, adaptive, randomised controlled trial of adding oseltamivir to usual care in patients aged 1 year and older presenting with influenza-like illness in primary care. The primary endpoint was time to recovery, defined as return to usual activities, with fever, headache, and muscle ache minor or absent. The trial was designed and powered to assess oseltamivir benefit overall and in 36 prespecified subgroups defined by age, comorbidity, previous symptom duration, and symptom severity, using a Bayesian piece-wise exponential primary analysis model. The trial is registered with the ISRCTN Registry, number ISRCTN 27908921. FINDINGS: Between Jan 15, 2016, and April 12, 2018, we recruited 3266 participants in 15 European countries during three seasonal influenza seasons, allocated 1629 to usual care plus oseltamivir and 1637 to usual care, and ascertained the primary outcome in 1533 (94%) and 1526 (93%). 1590 (52%) of 3059 participants had PCR-confirmed influenza infection. Time to recovery was shorter in participants randomly assigned to oseltamivir (hazard ratio 1·29, 95% Bayesian credible interval [BCrI] 1·20-1·39) overall and in 30 of the 36 prespecified subgroups, with estimated hazard ratios ranging from 1·13 to 1·72. The estimated absolute mean benefit from oseltamivir was 1·02 days (95% [BCrI] 0·74-1·31) overall, and in the prespecified subgroups, ranged from 0·70 (95% BCrI 0·30-1·20) in patients younger than 12 years, with less severe symptoms, no comorbidities, and shorter previous illness duration to 3·20 (95% BCrI 1·00-5·50) in patients aged 65 years or older who had more severe illness, comorbidities, and longer previous illness duration. Regarding harms, an increased burden of vomiting or nausea was observed in the oseltamivir group. INTERPRETATION: Primary care patients with influenza-like illness treated with oseltamivir recovered one day sooner on average than those managed by usual care alone. Older, sicker patients with comorbidities and longer previous symptom duration recovered 2-3 days sooner. FUNDING: European Commission's Seventh Framework Programme.
Assuntos
Antivirais/administração & dosagem , Influenza Humana/terapia , Oseltamivir/administração & dosagem , Atenção Primária à Saúde/métodos , Adolescente , Adulto , Idoso , Antivirais/uso terapêutico , Criança , Pré-Escolar , Terapia Combinada , Europa (Continente) , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Oseltamivir/uso terapêutico , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: Baloxavir marboxil is a selective inhibitor of influenza cap-dependent endonuclease. It has shown therapeutic activity in preclinical models of influenza A and B virus infections, including strains resistant to current antiviral agents. METHODS: We conducted two randomized, double-blind, controlled trials involving otherwise healthy outpatients with acute uncomplicated influenza. After a dose-ranging (10 to 40 mg) placebo-controlled trial, we undertook a placebo- and oseltamivir-controlled trial of single, weight-based doses of baloxavir (40 or 80 mg) in patients 12 to 64 years of age during the 2016-2017 season. The dose of oseltamivir was 75 mg twice daily for 5 days. The primary efficacy end point was the time to alleviation of influenza symptoms in the intention-to-treat infected population. RESULTS: In the phase 2 trial, the median time to alleviation of influenza symptoms was 23.4 to 28.2 hours shorter in the baloxavir groups than in the placebo group (P<0.05). In the phase 3 trial, the intention-to-treat infected population included 1064 patients; 84.8 to 88.1% of patients in each group had influenza A(H3N2) infection. The median time to alleviation of symptoms was 53.7 hours (95% confidence interval [CI], 49.5 to 58.5) with baloxavir, as compared with 80.2 hours (95% CI, 72.6 to 87.1) with placebo (P<0.001). The time to alleviation of symptoms was similar with baloxavir and oseltamivir. Baloxavir was associated with greater reductions in viral load 1 day after initiation of the regimen than placebo or oseltamivir. Adverse events were reported in 20.7% of baloxavir recipients, 24.6% of placebo recipients, and 24.8% of oseltamivir recipients. The emergence of polymerase acidic protein variants with I38T/M/F substitutions conferring reduced susceptibility to baloxavir occurred in 2.2% and 9.7% of baloxavir recipients in the phase 2 trial and phase 3 trial, respectively. CONCLUSIONS: Single-dose baloxavir was without evident safety concerns, was superior to placebo in alleviating influenza symptoms, and was superior to both oseltamivir and placebo in reducing the viral load 1 day after initiation of the trial regimen in patients with uncomplicated influenza. Evidence for the development of decreased susceptibility to baloxavir after treatment was also observed. (Funded by Shionogi; JapicCTI number, 153090, and CAPSTONE-1 ClinicalTrials.gov number, NCT02954354 .).
Assuntos
Antivirais/administração & dosagem , Influenza Humana/tratamento farmacológico , Oseltamivir/uso terapêutico , Oxazinas/administração & dosagem , Piridinas/administração & dosagem , Tiepinas/administração & dosagem , Triazinas/administração & dosagem , Adolescente , Adulto , Antivirais/efeitos adversos , Antivirais/uso terapêutico , Criança , Dibenzotiepinas , Método Duplo-Cego , Endonucleases/antagonistas & inibidores , Feminino , Humanos , Influenza Humana/virologia , Análise de Intenção de Tratamento , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Morfolinas , Oxazinas/efeitos adversos , Piridinas/efeitos adversos , Piridonas , Tiepinas/efeitos adversos , Triazinas/efeitos adversos , Carga Viral , Replicação Viral/efeitos dos fármacos , Adulto JovemRESUMO
Highly pathogenic avian influenza A(H5N8) viruses first emerged in China in 2010 and in 2014 spread throughout Asia and to Europe and the United States via migrating birds. Influenza A(H5N8) viruses were first detected in the Netherlands in 2014 and caused five outbreaks in poultry farms but were infrequently detected in wild birds. In 2016, influenza A(H5N8) viruses were reintroduced into the Netherlands, resulting in eight poultry farm outbreaks. This outbreak resulted in numerous dead wild birds with severe pathology. Phylogenetic analysis showed that the polymerase genes of these viruses had undergone extensive reassortment between outbreaks. Here, we investigated the differences in virulence between the 2014-15 and the 2016-17 outbreaks by characterizing the polymerase complex of influenza A(H5N8) viruses from both outbreaks. We found that viruses from the 2014-15 outbreak had significantly higher polymerase complex activity in both human and avian cell lines than did those from the 2016-17 outbreak. No apparent differences in the balance between transcription and replication of the viral genome were observed. Interestingly, the 2014-15 polymerase complexes induced significantly higher levels of interferon beta (IFN-ß) than the polymerase complexes of the 2016-17 outbreak viruses, mediated via retinoic acid-inducible gene I (RIG-I). Inoculation of primary duck cells with recombinant influenza A(H5N8) viruses, including viruses with reassorted polymerase complexes, showed that the polymerase complexes from the 2014-15 outbreak induced higher levels of IFN-ß despite relatively minor differences in replication capacity. Together, these data suggest that despite the lower levels of polymerase activity, the higher 2016-17 influenza A(H5N8) virus virulence may be attributed to the lower level of activation of the innate immune system.IMPORTANCE Compared to the 2014-15 outbreak, the 2016-17 outbreak of influenza A(H5N8) viruses in the Netherlands and Europe was more virulent; the number of dead or diseased wild birds found and the severity of pathological changes were higher during the 2016-17 outbreak. The polymerase complex plays an important role in influenza virus virulence, and the gene segments of influenza A(H5N8) viruses reassorted extensively between the outbreaks. In this study, the 2014-15 polymerase complexes were found to be more active, which is counterintuitive with the observed higher virulence of the 2016-17 outbreak viruses. Interestingly, the 2014-15 polymerase complexes also induced higher levels of IFN-ß. These findings suggest that the higher virulence of influenza A(H5N8) viruses from the 2016-17 outbreak may be related to the lower induction of IFN-ß. An attenuated interferon response could lead to increased dissemination, pathology, and mortality, as observed in (wild) birds infected during the 2016-2017 outbreak.
Assuntos
Proteínas Aviárias , Surtos de Doenças , Vírus da Influenza A Subtipo H5N8 , Influenza Aviária , Interferon beta , RNA Polimerase Dependente de RNA , Proteínas Virais , Animais , Proteínas Aviárias/genética , Proteínas Aviárias/imunologia , Coturnix , Cães , Patos , Células HEK293 , Humanos , Vírus da Influenza A Subtipo H5N8/genética , Vírus da Influenza A Subtipo H5N8/imunologia , Influenza Aviária/epidemiologia , Influenza Aviária/genética , Influenza Aviária/imunologia , Interferon beta/genética , Interferon beta/imunologia , Células Madin Darby de Rim Canino , RNA Polimerase Dependente de RNA/genética , RNA Polimerase Dependente de RNA/imunologia , Proteínas Virais/genética , Proteínas Virais/imunologiaRESUMO
Highly pathogenic avian influenza (HPAI) viruses are enzootic in wild birds and poultry and continue to cause human infections with high mortality. To date, more than 850 confirmed human cases of H5N1 virus infection have been reported, of which â¼60% were fatal. Global concern persists that these or similar avian influenza viruses will evolve into viruses that can transmit efficiently between humans, causing a severe influenza pandemic. It was shown previously that a change in receptor specificity is a hallmark for adaptation to humans and evolution toward a transmittable virus. Substantial genetic diversity was detected within the receptor binding site of hemagglutinin of HPAI A/H5N1 viruses, evolved during human infection, as detected by next-generation sequencing. Here, we investigated the functional impact of substitutions that were detected during these human infections. Upon rescue of 21 mutant viruses, most substitutions in the receptor binding site (RBS) resulted in viable virus, but virus replication, entry, and stability were often impeded. None of the tested substitutions individually resulted in a clear switch in receptor preference as measured with modified red blood cells and glycan arrays. Although several combinations of the substitutions can lead to human-type receptor specificity, accumulation of multiple amino acid substitutions within a single hemagglutinin during human infection is rare, thus reducing the risk of virus adaptation to humans.IMPORTANCE H5 viruses continue to be a threat for public health. Because these viruses are immunologically novel to humans, they could spark a pandemic when adapted to transmit between humans. Avian influenza viruses need several adaptive mutations to bind to human-type receptors, increase hemagglutinin (HA) stability, and replicate in human cells. However, knowledge on adaptive mutations during human infections is limited. A previous study showed substantial diversity within the receptor binding site of H5N1 during human infection. We therefore analyzed the observed amino acid changes phenotypically in a diverse set of assays, including virus replication, stability, and receptor specificity. None of the tested substitutions resulted in a clear step toward a human-adapted virus capable of aerosol transmission. It is notable that acquiring human-type receptor specificity needs multiple amino acid mutations, and that variability at key position 226 is not tolerated, reducing the risk of them being acquired naturally.
Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Virus da Influenza A Subtipo H5N1/genética , Receptores Virais/genética , Adaptação Fisiológica/genética , Substituição de Aminoácidos/genética , Animais , Sítios de Ligação/genética , Variação Biológica da População/genética , Aves , Cães , Hemaglutininas Virais/genética , Humanos , Vírus da Influenza A/genética , Influenza Aviária/virologia , Influenza Humana/virologia , Células Madin Darby de Rim Canino , Aves Domésticas , Ligação Proteica/genética , Receptores Virais/metabolismoRESUMO
BACKGROUND: CRISPR-Cas9, a technology enabling modification of the human genome, is developing rapidly. There have been calls for public debate to discuss its ethics, societal implications, and governance. So far, however, little is known about public attitudes on CRISPR-Cas9. This study contributes to a better understanding of public perspectives by exploring the various holistic perspectives Dutch citizens have on CRISPR-Cas9. METHODS: This study used Q methodology to identify different perspectives of Dutch citizens (N = 30) on the use of CRISPR-Cas9. The Q-sort method aims at segmenting audiences based on the structural characteristics of their perspectives. Participants individually ranked 32 statements about CRISPR-Cas9 and discussed their rankings in small groups. By-person factor analysis was performed using PQMethod. Participants' contributions to the discussions were used to further make sense of the audience segments identified. RESULTS: Five perspectives on CRISPR-Cas9 were identified: (1) pragmatic optimism (2) concerned scepticism; (3) normative optimism; (4) enthusiastic support; and (5) benevolent generalism. Each perspective represents a unique position motivated by different ranking rationales. Sorting rationales included improving health, preventing negative impacts on society, and fear of a slippery slope. Overall, there is broad, but not universal support for medical uses of CRISPR-Cas9. CONCLUSIONS: Research on CRISPR-Cas9 should prioritise the broadly supported applications of the technology. Research and public debates on CRISPR-Cas9, its uses, its broader implications, and the governance of CRISPR-Cas9 are recommended. A discourse that includes all perspectives can contribute to the embedding of future uses of CRISPR-Cas9 in society. This study shows that Q methodology followed by group discussions enables citizens to contribute meaningfully to discourses about research.
Assuntos
Pesquisa Biomédica/ética , Sistemas CRISPR-Cas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Edição de Genes/ética , Melhoramento Genético/ética , Opinião Pública , Genoma Humano , Humanos , Países BaixosRESUMO
BACKGROUND: Single-dose baloxavir rapidly reduces influenza virus titers and symptoms in patients with uncomplicated influenza, but viruses with reduced in vitro susceptibility due to amino acid substitutions at position 38 of polymerase acidic protein (PA/I38X) sometimes emerge. METHODS: We evaluated the kinetics, risk factors, and effects on clinical and virologic outcomes of emergence of PA/I38X-substituted viruses. RESULTS: Viruses containing PA/I38X substitutions were identified 3-9 days after baloxavir treatment in 9.7% (36/370) of patients, of whom 85.3% had transient virus titer rises. Median time to sustained cessation of infectious virus detection was 192, 48, and 96 hours in the baloxavir recipients with PA/I38X-substituted viruses, without PA/I38X-substituted viruses, and placebo recipients, respectively. The corresponding median times to alleviation of symptoms were 63.1, 51.0, and 80.2 hours, respectively. After day 5, symptom increases occurred in 11.5%, 8.0%, and 13.0%, respectively, and in 8.9% of oseltamivir recipients. Variant virus emergence was associated with lower baseline neutralizing antibody titers. CONCLUSIONS: The emergence of viruses with PA/I38X substitutions following baloxavir treatment was associated with transient rises in infectious virus titers, prolongation of virus detectability, initial delay in symptom alleviation, and uncommonly with symptom rebound. The potential transmissibility of PA/I38X-substituted viruses requires careful study. CLINICAL TRIAL REGISTRATION: NCT02954354.
Assuntos
Antivirais/uso terapêutico , Farmacorresistência Viral/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/genética , Influenza Humana/tratamento farmacológico , Oxazinas/uso terapêutico , Piridinas/uso terapêutico , Tiepinas/uso terapêutico , Triazinas/uso terapêutico , Adolescente , Adulto , Substituição de Aminoácidos , Antivirais/farmacologia , Criança , Dibenzotiepinas , Método Duplo-Cego , Feminino , Humanos , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Morfolinas , Oseltamivir/uso terapêutico , Oxazinas/farmacologia , Piridinas/farmacologia , Piridonas , Fatores de Risco , Tiepinas/farmacologia , Resultado do Tratamento , Triazinas/farmacologia , Carga Viral/efeitos dos fármacos , Adulto JovemRESUMO
BACKGROUND: Since their emergence in Indonesia in 2005, 200 human infections with clade 2.1 highly pathogenic avian influenza A/H5N1 virus have been reported, associated with exceptionally high mortality (84%) compared to regions affected by other genetic clades of this virus. To provide potential clues towards understanding this high mortality, detailed clinical virological analyses were performed in specimens from 180 H5N1 patients, representing 90% of all Indonesian patients and 20% of reported H5N1-infected patients globally. METHODS: H5N1 RNA was quantified in available upper- and lower-respiratory tract specimens as well as fecal and blood samples from 180 patients with confirmed infection between 2005 and 2017. Mutations in the neuraminidase and M2 genes that confer resistance to oseltamivir and adamantanes were assessed. Fatal and nonfatal cases were compared. RESULTS: High viral RNA loads in nasal and pharyngeal specimens were associated with fatal outcome. Mortality increased over time during the study period, which correlated with increasing viral RNA loads on admission. Furthermore, the prevalence of amantadine resistance-conferring M2 mutations increased over time, and viral loads were higher in patients infected with viruses that harbored these mutations. Compared to observations from other regions, viral RNA was detected more frequently in feces (80%) and particularly in blood (85%), and antiviral responses to oseltamivir appeared less pronounced. CONCLUSIONS: These observations confirm the association of viral load with outcome of human H5N1 infections and suggest potential differences in virulence and antiviral responses to oseltamivir that may explain the exceptionally high mortality related to clade 2.1 H5N1 infections in Indonesia.
Assuntos
Antivirais , Virus da Influenza A Subtipo H5N1 , Influenza Aviária , Influenza Humana , Animais , Antivirais/uso terapêutico , Humanos , Indonésia/epidemiologia , Virus da Influenza A Subtipo H5N1/genética , Influenza Humana/epidemiologia , Neuraminidase , Oseltamivir/uso terapêuticoRESUMO
OBJECTIVE: To determine the yield of preoperative screening for COVID-19 with chest CT and RT-PCR in patients without COVID-19 symptoms. SUMMARY OF BACKGROUND DATA: Many centers are currently screening surgical patients for COVID-19 using either chest CT, RT-PCR or both, due to the risk for worsened surgical outcomes and nosocomial spread. The optimal design and yield of such a strategy are currently unknown. METHODS: This multicenter study included consecutive adult patients without COVID-19 symptoms who underwent preoperative screening using chest CT and RT-PCR before elective or emergency surgery under general anesthesia. RESULTS: A total of 2093 patients without COVID-19 symptoms were included in 14 participating centers; 1224 were screened by CT and RT-PCR and 869 by chest CT only. The positive yield of screening using a combination of chest CT and RT-PCR was 1.5% [95% confidence interval (CI): 0.8-2.1]. Individual yields were 0.7% (95% CI: 0.2-1.1) for chest CT and 1.1% (95% CI: 0.6-1.7) for RT-PCR; the incremental yield of chest CT was 0.4%. In relation to COVID-19 community prevalence, up to â¼6% positive RT-PCR was found for a daily hospital admission rate >1.5 per 100,000 inhabitants, and around 1.0% for lower prevalence. CONCLUSIONS: One in every 100 patients without COVID-19 symptoms tested positive for SARS-CoV-2 with RT-PCR; this yield increased in conjunction with community prevalence. The added value of chest CT was limited. Preoperative screening allowed us to take adequate precautions for SARS-CoV-2 positive patients in a surgical population, whereas negative patients needed only routine procedures.
Assuntos
Infecções Assintomáticas , COVID-19/diagnóstico , Tratamento de Emergência , Programas de Rastreamento/estatística & dados numéricos , Cuidados Pré-Operatórios/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2 , Procedimentos Cirúrgicos Operatórios , Tórax/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Procedimentos Cirúrgicos Eletivos , Humanos , Estudos RetrospectivosRESUMO
Since the initial detection in 2003, Indonesia has reported 200 human cases of highly pathogenic avian influenza H5N1 (HPAI H5N1), associated with an exceptionally high case fatality rate (84%) compared to other geographical regions affected by other genetic clades of the virus. However, there is limited information on the genetic diversity of HPAI H5N1 viruses, especially those isolated from humans in Indonesia. In this study, the genetic and antigenic characteristics of 35 HPAI H5N1 viruses isolated from humans were analyzed. Full genome sequences were analyzed for the presence of substitutions in the receptor binding site, and polymerase complex, as markers for virulence or human adaptation, as well as antiviral drug resistance substitutions. Only a few substitutions associated with human adaptation were observed, a remarkably low prevalence of the human adaptive substitution PB2-E627K, which is common during human infection with other H5N1 clades and a known virulence marker for avian influenza viruses during human infections. In addition, the antigenic profile of these Indonesian HPAI H5N1 viruses was determined using serological analysis and antigenic cartography. Antigenic characterization showed two distinct antigenic clusters, as observed previously for avian isolates. These two antigenic clusters were not clearly associated with time of virus isolation. This study provides better insight in genetic diversity of H5N1 viruses during human infection and the presence of human adaptive markers. These findings highlight the importance of evaluating virus genetics for HPAI H5N1 viruses to estimate the risk to human health and the need for increased efforts to monitor the evolution of H5N1 viruses across Indonesia.
Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Virus da Influenza A Subtipo H5N1/imunologia , Influenza Aviária/imunologia , Influenza Humana/imunologia , Animais , Antígenos Virais/genética , Antígenos Virais/imunologia , Aves/virologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/patogenicidade , Influenza Aviária/genética , Influenza Aviária/virologia , Influenza Humana/genética , Influenza Humana/virologia , Filogenia , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/virologiaRESUMO
In this study, we developed and validated two reliable high-performance liquid chromatography (HPLC) methods for the qualitative detection of six oral ß-lactams, which are commonly used in pediatric patients with acute respiratory infections (ARIs). Two distinct reverse-phase chromatographic separations of six ß-lactams were obtained. Four ß-lactams (cefadroxil, cephalexin, cefaclor and cefixime) in urine were separated using a gradient program with a mobile phase consisting of K2 HPO4 buffer (20 mm, pH 2.8) and acetonitrile on a LichroCART 250 × 4.6 mm, Purospher STAR C18 end-capped (5 µm) column. Two remained ß-lactams (amoxicillin and cefuroxime) were analyzed using a gradient elution with the mobile phase containing K2 HPO4 buffer (20 mm, pH 3.0) and acetonitrile on a LichroCart® Purospher Star C8 end-capped column (5 µm, 125 × 4.6 mm). Good linearity within the range of 0.3-30 µg/ml for cefadroxil, cephalexin, cefaclor and cefixime, and 0.2-20 µg/ml for amoxicillin and cefuroxime, was attained. The precisions were <14%. The accuracies ranged from 85.87 to 102.8%. The two validated methods were then applied to determine these six antibiotics in 553 urine samples of pediatric patients with ARIs. As a result, 32.2% were positive with one or more of six tested ß-lactams. Cefixime was the most commonly detected agent, accounting for 9.8% of enrolled patients.