RESUMEN
Fusion of enveloped viruses with endosomal membranes and subsequent release of the viral genome into the cytoplasm are crucial to the viral infection cycle. It is often modeled by performing fusion between virus particles and target lipid vesicles. We utilized fluorescence microscopy to characterize the kinetic aspects of the transfer of influenza viral ribonucleoprotein (vRNP) complexes to target vesicles and their spatial distribution within the fused volumes to gain deeper insight into the mechanistic aspects of endosomal escape. The fluorogenic RNA-binding dye QuantiFluor (Promega) was found to be well-suited for direct and sensitive microscopic observation of vRNPs which facilitated background-free detection and kinetic analysis of fusion events on a single particle level. To determine the extent to which the viral contents are transferred to the target vesicles through the fusion pore, we carried out virus-vesicle fusion in a side-by-side fashion. Measurement of the Euclidean distances between the centroids of superlocalized membrane and content dye signals within the fused volumes allowed determination of any symmetry (or the lack thereof) between them as expected in the event of transfer (or the lack thereof) of vRNPs, respectively. We found that, in the case of fusion between viruses and 100 nm target vesicles, â¼39% of the events led to transfer of viral contents to the target vesicles. This methodology provides a rapid, generic, and cell-free way to assess the inhibitory effects of antiviral drugs and therapeutics on the endosomal escape behavior of enveloped viruses.
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Colorantes Fluorescentes , Colorantes Fluorescentes/química , Humanos , Microscopía Fluorescente/métodos , Endosomas/metabolismo , Endosomas/virología , Animales , Ribonucleoproteínas/metabolismo , Orthomyxoviridae/aislamiento & purificación , Células de Riñón Canino Madin Darby , CinéticaRESUMEN
In this study, we investigated the concentration of airborne influenza virus in daycare centers and influencing factors, such as common cold prevalence, air pollutants, and meteorological factors. A total of 209 air samples were collected from daycare centers in Kaohsiung and the influenza virus was analyzed using real-time quantitative polymerase chain reaction. Air pollutants and metrological factors were measured using real-time monitoring equipment. Winter had the highest positive rates of airborne influenza virus and the highest prevalence of the common cold, followed by summer and autumn. The concentration of CO was significantly positively correlated with airborne influenza virus. Daycare center A, with natural ventilation and air condition systems, had a higher concentration of airborne influenza A virus, airborne fungi, and airborne bacteria, as well as a higher prevalence of the common cold, than daycare center B, with a mechanical ventilation system and air purifiers, while the concentrations of CO2, CO, and UFPs in daycare center A were lower than those in daycare center B. We successfully detected airborne influenza virus in daycare centers, demonstrating that aerosol sampling for influenza can provide novel epidemiological insights and inform the management of influenza in daycare centers.
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Microbiología del Aire , Guarderías Infantiles , Gripe Humana , Estaciones del Año , Humanos , Gripe Humana/epidemiología , Gripe Humana/virología , Gripe Humana/transmisión , Virus de la Influenza A/aislamiento & purificación , Virus de la Influenza A/genética , Orthomyxoviridae/aislamiento & purificación , Orthomyxoviridae/genética , Contaminantes Atmosféricos/análisis , Resfriado Común/epidemiología , Resfriado Común/virología , Resfriado Común/transmisión , Preescolar , Prevalencia , Monitoreo del AmbienteRESUMEN
BACKGROUND: Novel influenza viruses pose a potential pandemic risk, and rapid detection of infections in humans is critical to characterizing the virus and facilitating the implementation of public health response measures. METHODS: We use a probabilistic framework to estimate the likelihood that novel influenza virus cases would be detected through testing in different community and healthcare settings (urgent care, emergency department, hospital, and intensive care unit [ICU]) while at low frequencies in the United States. Parameters were informed by data on seasonal influenza virus activity and existing testing practices. RESULTS: In a baseline scenario reflecting the presence of 100 novel virus infections with similar severity to seasonal influenza viruses, the median probability of detecting at least one infection per month was highest in urgent care settings (72%) and when community testing was conducted at random among the general population (77%). However, urgent care testing was over 15 times more efficient (estimated as the number of cases detected per 100,000 tests) due to the larger number of tests required for community testing. In scenarios that assumed increased clinical severity of novel virus infection, median detection probabilities increased across all healthcare settings, particularly in hospitals and ICUs (up to 100%) where testing also became more efficient. CONCLUSIONS: Our results suggest that novel influenza virus circulation is likely to be detected through existing healthcare surveillance, with the most efficient testing setting impacted by the disease severity profile. These analyses can help inform future testing strategies to maximize the likelihood of novel influenza detection.
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Gripe Humana , Humanos , Gripe Humana/diagnóstico , Gripe Humana/epidemiología , Gripe Humana/virología , Estados Unidos/epidemiología , Orthomyxoviridae/aislamiento & purificación , Orthomyxoviridae/genética , Orthomyxoviridae/clasificación , Monitoreo EpidemiológicoRESUMEN
Influenza vaccines, which are recommended by the World Health Organization (WHO), are the most effective preventive measure against influenza virus infection. Madin-Darby canine kidney (MDCK) cell culture is an emerging technology used to produce influenza vaccines. One challenge when purifying influenza vaccines using this cell culture system is to efficiently remove impurities, especially host cell double-stranded DNA (dsDNA) and host cell proteins (HCPs), for safety assurance. In this study, we optimized ion-exchange chromatography methods to harvest influenza viruses from an MDCK cell culture broth, the first step in influenza vaccine purification. Bind/elute was chosen as the mode of operation for simplicity. The anion-exchange Q chromatography method was able to efficiently remove dsDNA and HCPs, but the recovery rate for influenza viruses was low. However, the cation-exchange SP process was able to simultaneously achieve high dsDNA and HCP removal and high influenza virus recovery. For the SP process to work, the clarified cell culture broth needed to be diluted to reduce its ionic strength, and the optimal dilution rate was determined to be 1:2 with purified water. The SP process yielded a virus recovery rate exceeding 90%, as measured using a hemagglutination units (HAUs) assay, with removal efficiencies over 97% for HCPs and over 99% for dsDNA. Furthermore, the general applicability of the SP chromatography method was demonstrated with seven strains of influenza viruses recommended for seasonal influenza vaccine production, including H1N1, H3N2, B (Victoria), and B (Yamagata) strains, indicating that the SP process could be utilized as a platform process. The SP process developed in this study showed four advantages: (1) simple operation, (2) a high recovery rate for influenza viruses, (3) a high removal rate for major impurities, and (4) general applicability.
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Vacunas contra la Influenza , Virión , Animales , Perros , Células de Riñón Canino Madin Darby , Virión/aislamiento & purificación , Cromatografía por Intercambio Iónico/métodos , Cultivo de Virus/métodos , Orthomyxoviridae/aislamiento & purificación , Técnicas de Cultivo de Célula/métodosRESUMEN
BACKGROUND: Influenza and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are both respiratory viruses with similar clinical manifestations and modes of transmission. This study describes influenza data before and during the coronavirus disease pandemic (COVID-19) in Cameroon and SARS-CoV-2 data during the pandemic period. METHODS: The study ran from 2017 to 2022, and data were divided into two periods: before (2017-2019) and during (2020-2022) the COVID-19 pandemic. Nasopharyngeal samples collected from persons with respiratory illness were tested for influenza using the Centers for Disease Control and Prevention (CDC) typing and subtyping assays. During the COVID-19 pandemic, the respiratory specimens were simultaneously tested for SARS-CoV-2 using the DaAn gene protocol or the Abbott real-time SARS-CoV-2 assay. The WHO average curve method was used to compare influenza virus seasonality before and during the pandemic. RESULTS: A total of 6246 samples were tested. Influenza virus detection rates were significantly higher in the pre-pandemic period compared to the pandemic period (30.8% vs. 15.5%; p < 0.001). Meanwhile, the SARS-CoV-2 detection rate was 2.5%. A change in the seasonality of influenza viruses was observed from a bi-annual peak before the pandemic to no clear seasonal pattern during the pandemic. The age groups 2-4 and 5-14 years were significantly associated with higher influenza positivity rates in both pre-pandemic and pandemic periods. For SARS-CoV-2, all age groups above 15 years were the most affected population. CONCLUSION: The COVID-19 pandemic had a significant impact on the seasonal influenza by changing the seasonality of the virus and reducing its detection rates.
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COVID-19 , Gripe Humana , SARS-CoV-2 , Humanos , Camerún/epidemiología , Gripe Humana/epidemiología , Gripe Humana/virología , COVID-19/epidemiología , COVID-19/diagnóstico , COVID-19/virología , Adolescente , Adulto , Niño , Preescolar , Persona de Mediana Edad , Adulto Joven , Femenino , Masculino , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Lactante , Anciano , Nasofaringe/virología , Estaciones del Año , Pandemias , Orthomyxoviridae/aislamiento & purificación , Orthomyxoviridae/genética , Orthomyxoviridae/clasificaciónRESUMEN
Influenza viruses pose a significant public health threat, necessitating comprehensive surveillance strategies to enhance early detection and preventive measures. This systematic review investigates the incidence of influenza viruses in wastewater matrices, aiming to elucidate the potential implications for public health. The study synthesizes existing literature, employing rigorous inclusion criteria to identify relevant studies conducted globally. The essence of the problem lies in the gaps of traditional surveillance methods, which often rely on clinical data and may underestimate the true prevalence of influenza within communities. Wastewater-based epidemiology offers a novel approach to supplementing these conventional methods, providing a broader and more representative assessment of viral circulation. This review systematically examines the methodologies employed in the selected studies, including virus concentration techniques and molecular detection methods, to establish a standardized framework for future research. Our findings reveal a consistent presence of influenza viruses in diverse wastewater matrices across different geographic locations and seasons. Recommendations for future research include the standardization of sampling protocols, improvement of virus concentration methods, and the integration of wastewater surveillance into existing public health frameworks. In conclusion, this systematic review contributes to the understanding of influenza dynamics in wastewater matrices, offering valuable insights for public health practitioners and policymakers. Implementation of wastewater surveillance alongside traditional methods can enhance the resilience of public health systems and better prepare communities for the challenges posed by influenza outbreaks.
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Gripe Humana , Salud Pública , Aguas Residuales , Aguas Residuales/virología , Humanos , Gripe Humana/epidemiología , Gripe Humana/prevención & control , Gripe Humana/virología , Incidencia , Orthomyxoviridae/aislamiento & purificaciónRESUMEN
"Swientists" hunt for influenza virus at hog shows, hoping to cut off the next pandemic at the pen.
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Gripe Humana , Infecciones por Orthomyxoviridae , Orthomyxoviridae , Pandemias , Zoonosis Virales , Humanos , Exposiciones como Asunto , Gripe Humana/prevención & control , Gripe Humana/transmisión , Orthomyxoviridae/aislamiento & purificación , Pandemias/prevención & control , Porcinos , Zoonosis Virales/transmisión , Masculino , Femenino , Niño , Infecciones por Orthomyxoviridae/transmisión , Infecciones por Orthomyxoviridae/virologíaRESUMEN
Since December 2019 the world has been facing the outbreak of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Identification of infected patients and discrimination from other respiratory infections have so far been accomplished by using highly specific real-time PCRs. Here we present a rapid multiplex approach (RespiCoV), combining highly multiplexed PCRs and MinION sequencing suitable for the simultaneous screening for 41 viral and five bacterial agents related to respiratory tract infections, including the human coronaviruses NL63, HKU1, OC43, 229E, Middle East respiratory syndrome coronavirus, SARS-CoV, and SARS-CoV-2. RespiCoV was applied to 150 patient samples with suspected SARS-CoV-2 infection and compared with specific real-time PCR. Additionally, several respiratory tract pathogens were identified in samples tested positive or negative for SARS-CoV-2. Finally, RespiCoV was experimentally compared to the commercial RespiFinder 2SMART multiplex screening assay (PathoFinder, The Netherlands).
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Bacterias/genética , COVID-19/diagnóstico , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Virus ARN/genética , Infecciones del Sistema Respiratorio/diagnóstico , SARS-CoV-2/genética , Bacterias/aislamiento & purificación , COVID-19/virología , Coronavirus/genética , Coronavirus/aislamiento & purificación , ADN Bacteriano/química , ADN Bacteriano/metabolismo , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/aislamiento & purificación , Humanos , Reacción en Cadena de la Polimerasa Multiplex , Nanoporos , Orthomyxoviridae/genética , Orthomyxoviridae/aislamiento & purificación , Virus ARN/aislamiento & purificación , ARN Viral/química , ARN Viral/metabolismo , Infecciones del Sistema Respiratorio/microbiología , Infecciones del Sistema Respiratorio/virología , SARS-CoV-2/aislamiento & purificaciónRESUMEN
BACKGROUND: In the context of COVID-19 pandemic in Catalonia (Spain), the present study analyses respiratory samples collected by the primary care network using Acute Respiratory Infections Sentinel Surveillance System (PIDIRAC) during the 2019-2020 season to complement the pandemic surveillance system in place to detect SARS-CoV-2. The aim of the study is to describe whether SARS-CoV-2 was circulating before the first confirmed case was detected in Catalonia, on February 25th, 2020. METHODS: The study sample was made up of all samples collected by the PIDIRAC primary care network as part of the Influenza and Acute Respiratory Infections (ARI) surveillance system activities. The study on respiratory virus included coronavirus using multiple RT-PCR assays. All positive samples for human coronavirus were subsequently typed for HKU1, OC43, NL63, 229E. Every respiratory sample was frozen at-80°C and retrospectively studied for SARS-CoV-2 detection. A descriptive study was performed, analysing significant differences among variables related to SARS-CoV- 2 cases comparing with rest of coronaviruses cases through a bivariate study with Chi-squared test and statistical significance at 95%. RESULTS: Between October 2019 and April 2020, 878 respiratory samples from patients with acute respiratory infection or influenza syndrome obtained by PIDIRAC were analysed. 51.9% tested positive for influenza virus, 48.1% for other respiratory viruses. SARS-CoV-2 was present in 6 samples. The first positive SARS-CoV-2 case had symptom onset on 2 March 2020. These 6 cases were 3 men and 3 women, aged between 25 and 50 years old. 67% had risk factors, none had previous travel history nor presented viral coinfection. All of them recovered favourably. CONCLUSION: Sentinel Surveillance PIDIRAC enhances global epidemiological surveillance by allowing confirmation of viral circulation and describes the epidemiology of generalized community respiratory viruses' transmission in Catalonia. The system can provide an alert signal when identification of a virus is not achieved in order to take adequate preparedness measures.
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COVID-19/diagnóstico , Coronavirus/clasificación , Orthomyxoviridae/clasificación , ARN Viral/genética , Infecciones del Sistema Respiratorio/virología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/epidemiología , Niño , Preescolar , Coronavirus/genética , Coronavirus/aislamiento & purificación , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Orthomyxoviridae/genética , Orthomyxoviridae/aislamiento & purificación , Atención Primaria de Salud , Estudios Retrospectivos , Vigilancia de Guardia , España/epidemiología , Adulto JovenRESUMEN
Influenza affects millions of people worldwide and can result in severe sickness and even death. The best method of prevention is vaccination; however, the seasonal influenza vaccine often suffers from low efficacy and requires yearly vaccination due to changes in strain and viral mutations. More conserved universal influenza antigens like M2 ectodomain (M2e) and the stalk region of hemagglutinin (HA stalk) have been used clinically but often suffer from low antigenicity. To increase antigenicity, universal antigens have been formulated using nano/microparticles as vaccine carriers against influenza. Utilizing polymers, liposomes, metal, and protein-based particles, indicators of immunity and protection in mouse, pig, ferrets, and chicken models of influenza have been shown. In this review, seasonal and universal influenza vaccine formulations comprised of these materials including their physiochemical properties, fabrication, characterization, and biologic responses in vivo are highlighted. The review is concluded with future perspectives for nano/microparticles as carrier systems and other considerations within the universal influenza vaccine delivery landscape. Graphical Abstract.
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Sistemas de Liberación de Medicamentos , Vacunas contra la Influenza/administración & dosificación , Gripe Humana/prevención & control , Animales , Antígenos Virales/inmunología , Química Farmacéutica/métodos , Modelos Animales de Enfermedad , Humanos , Vacunas contra la Influenza/inmunología , Gripe Humana/inmunología , Gripe Humana/virología , Microesferas , Nanopartículas , Orthomyxoviridae/inmunología , Orthomyxoviridae/aislamiento & purificación , Vacunación/métodosRESUMEN
Importance: A critical need exists in low-income and middle-income countries for low-cost, low-tech, yet highly reliable and scalable testing for SARS-CoV-2 virus that is robust against circulating variants. Objective: To assess whether a smartphone-based assay is suitable for SARS-CoV-2 and influenza virus testing without requiring specialized equipment, accessory devices, or custom reagents. Design, Setting, and Participants: This cohort study enrolled 2 subgroups of participants (symptomatic and asymptomatic) at Santa Barbara Cottage Hospital. The symptomatic group consisted of 20 recruited patients who tested positive for SARS-CoV-2 with symptoms; 30 asymptomatic patients were recruited from the same community, through negative admission screening tests for SARS-CoV-2. The smartphone-based real-time loop-mediated isothermal amplification (smaRT-LAMP) was first optimized for analysis of human saliva samples spiked with either SARS-CoV-2 or influenza A or B virus; these results then were compared with those obtained by side-by-side analysis of spiked samples using the Centers for Disease Control and Prevention (CDC) criterion-standard reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) assay. Next, both assays were used to test for SARS-CoV-2 and influenza viruses present in blinded clinical saliva samples obtained from 50 hospitalized patients. Statistical analysis was performed from May to June 2021. Exposures: Testing for SARS-CoV-2 and influenza A and B viruses. Main Outcomes and Measures: SARS-CoV-2 and influenza infection status and quantitative viral load were determined. Results: Among the 50 eligible participants with no prior SARS-CoV-2 infection included in the study, 29 were men. The mean age was 57 years (range, 21 to 93 years). SmaRT-LAMP exhibited 100% concordance (50 of 50 patient samples) with the CDC criterion-standard diagnostic for SARS-CoV-2 sensitivity (20 of 20 positive and 30 of 30 negative) and for quantitative detection of viral load. This platform also met the CDC criterion standard for detection of clinically similar influenza A and B viruses in spiked saliva samples (n = 20), and in saliva samples from hospitalized patients (50 of 50 negative). The smartphone-based LAMP assay was rapid (25 minutes), sensitive (1000 copies/mL), low-cost (<$7/test), and scalable (96 samples/phone). Conclusions and Relevance: In this cohort study of saliva samples from patients, the smartphone-based LAMP assay detected SARS-CoV-2 infection and exhibited concordance with RT-qPCR tests. These findings suggest that this tool could be adapted in response to novel CoV-2 variants and other pathogens with pandemic potential including influenza and may be useful in settings with limited resources.
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COVID-19 , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico , Orthomyxoviridae/aislamiento & purificación , SARS-CoV-2/aislamiento & purificación , Teléfono Inteligente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estados Unidos , Adulto JovenRESUMEN
Membrane-based rapid test reagents including immunochromatography are widely used in clinical practice. Recently, high-sensitive reagents based on the immunochromatography method, such as silver amplification method and time resolved fluorescence method for influenza testing, has been developed and early confirmation of infection can be achieved. Furthermore, genetic testing, automated all the steps from extraction till detection, is getting popular. Genetic testing of mycoplasma by Smart Gene Myco system and Coronavirus disease 2019 (COVID-19) test is a good example of membrane-based rapid test reagents. This system uses silica particle-containing membrane filter and enable to shorten the assay time by automates pre-treatment process for removing contamination substances in the sample which affect polymerase-chain-reaction amplification. We hope utilized genetic testing application will help quick confirmation of COVID-19 positive patient and prevent the collapse of medical system under COVID-19 development.
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Cromatografía de Afinidad/métodos , Sistemas de Atención de Punto , COVID-19/diagnóstico , COVID-19/virología , Prueba de COVID-19 , Pruebas Genéticas , Humanos , Gripe Humana/diagnóstico , Gripe Humana/virología , Orthomyxoviridae/genética , Orthomyxoviridae/aislamiento & purificación , Reacción en Cadena de la Polimerasa , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificaciónRESUMEN
In this era, the novel Coronavirus, referred to as Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), a life-threatening virus with a high mortality rate (4.2%) and with no absolute treatment as of yet, may ultimately result in acute respiratory distress syndrome (ARDS). ARDS is one of the fatal complications, highlighted by pulmonary infiltration and severe hypoxemia. This condition can be developed from primary lung inflammation caused by various viruses, particularly influenza viruses, some of the most common human pathogens. Due to this issue, many studies explored several approaches for ARDS treatment. Lung transplantation has been claimed as an efficient cure for severe ARDS and Influenza, which can also be offered for treating critical lung complications of SARS-CoV-2. Thereupon, to the best of our knowledge for the first time, we aimed to review all available data about capability of lung transplantation for the treatment of critically ill patients with ARDS, Influenza, and SARS-CoV-2.
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COVID-19/cirugía , Gripe Humana/cirugía , Trasplante de Pulmón , Neumonía Viral , COVID-19/diagnóstico , Humanos , Gripe Humana/diagnóstico , Trasplante de Pulmón/efectos adversos , Trasplante de Pulmón/métodos , Orthomyxoviridae/aislamiento & purificación , Neumonía Viral/etiología , Neumonía Viral/cirugía , SARS-CoV-2/aislamiento & purificación , Índice de Severidad de la EnfermedadRESUMEN
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has forced the implementation of unprecedented public health measures strategies which might also have a significant impact on the spreading of other viral pathogens such as influenza and Respiratory Syncytial Virus (RSV) . The present study compares the incidences of the most relevant respiratory viruses before and during the SARS-CoV-2 pandemic in emergency room patients. We analyzed the results of in total 14,946 polymerase chain reaction point-of-care tests (POCT-PCR) for Influenza A, Influenza B, RSV and SARS-CoV-2 in an adult and a pediatric emergency room between December 1, 2018 and March 31, 2021. Despite a fivefold increase in the number of tests performed, the positivity rate for Influenza A dropped from 19.32% (165 positives of 854 tests in 2018/19), 14.57% (149 positives of 1023 in 2019-20) to 0% (0 positives of 4915 tests) in 2020/21. In analogy, the positivity rate for Influenza B and RSV dropped from 0.35 to 1.47%, respectively, 10.65-21.08% to 0% for both in 2020/21. The positivity rate for SARS-CoV2 reached 9.74% (110 of 1129 tests performed) during the so-called second wave in December 2020. Compared to the two previous years, seasonal influenza and RSV incidence was eliminated during the COVID-19 pandemic. Corona-related measures and human behavior patterns could lead to a significant decline or even complete suppression of other respiratory viruses such as influenza and RSV.
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COVID-19/epidemiología , Gripe Humana/diagnóstico , Pruebas en el Punto de Atención/estadística & datos numéricos , Infecciones por Virus Sincitial Respiratorio/diagnóstico , COVID-19/virología , Hospitales/estadística & datos numéricos , Humanos , Incidencia , Gripe Humana/epidemiología , Gripe Humana/virología , Orthomyxoviridae/genética , Orthomyxoviridae/aislamiento & purificación , Orthomyxoviridae/fisiología , Pandemias , Reacción en Cadena de la Polimerasa , Infecciones por Virus Sincitial Respiratorio/epidemiología , Infecciones por Virus Sincitial Respiratorio/virología , Virus Sincitial Respiratorio Humano/genética , Virus Sincitial Respiratorio Humano/aislamiento & purificación , Virus Sincitial Respiratorio Humano/fisiología , Estudios RetrospectivosRESUMEN
BACKGROUND: Cell-culture-derived influenza vaccines may enable a closer antigenic match to circulating strains of influenza virus by avoiding egg-adapted mutations. METHODS: We evaluated the efficacy of a cell-culture-derived quadrivalent inactivated influenza vaccine (IIV4c) using a Madin-Darby canine kidney cell line in children and adolescents 2 to less than 18 years of age. During three influenza seasons, participants from eight countries were enrolled in an observer-blinded, randomized clinical trial comparing IIV4c with a noninfluenza vaccine (meningococcal ACWY). All the participants received a dose of a trial vaccine. Children 2 to less than 9 years of age without previous influenza vaccination who were assigned to the IIV4c group received a second dose on day 29; their counterparts who were assigned to the comparator group received placebo. Participants were followed for at least 180 days for efficacy and safety. The presence of influenza virus in nasopharyngeal swabs from participants with influenza-like illness was confirmed by reverse-transcriptase-polymerase-chain-reaction assay and viral culture. A Cox proportional-hazards model was used to evaluate the efficacy of IIV4c as measured by the first occurrence of laboratory-confirmed type A or B influenza (primary end point). RESULTS: Between 2017 and 2019, a total of 4514 participants were randomly assigned to receive IIV4c or the meningococcal ACWY vaccine. Laboratory-confirmed influenza occurred in 175 of 2257 participants (7.8%) in the IIV4c group and in 364 of 2252 participants (16.2%) in the comparator group, and the efficacy of IIV4c was 54.6% (95% confidence interval [CI], 45.7 to 62.1). Efficacy was 80.7% (95% CI, 69.2 to 87.9) against influenza A/H1N1, 42.1% (95% CI, 20.3 to 57.9) against influenza A/H3N2, and 47.6% (95% CI, 31.4 to 60.0) against influenza B. IIV4c showed consistent vaccine efficacy in subgroups according to age, sex, race, and previous influenza vaccination. The incidences of adverse events were similar in the IIV4c group and the comparator group. CONCLUSIONS: IIV4c provided protection against influenza in healthy children and adolescents across seasons, regardless of previous influenza vaccination. (Funded by Seqirus; EudraCT number, 2016-002883-15; ClinicalTrials.gov number, NCT03165617.).
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Inmunogenicidad Vacunal , Vacunas contra la Influenza/inmunología , Gripe Humana/prevención & control , Adolescente , Anticuerpos Antivirales/sangre , Niño , Preescolar , Femenino , Humanos , Vacunas contra la Influenza/efectos adversos , Masculino , Vacunas Meningococicas/inmunología , Orthomyxoviridae/aislamiento & purificación , Modelos de Riesgos Proporcionales , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Método Simple Ciego , Vacunas de Productos Inactivados/inmunologíaRESUMEN
Measures intended to limit the spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus at the start of the coronavirus disease 2019 (COVID-19) pandemic resulted in a rapid decrease in other respiratory pathogens. Herein, we describe the trends of respiratory pathogens in a major metropolitan health care system central microbiology reference laboratory before and during the COVID-19 pandemic, with attention to when COVID-19 mitigation measures were implemented and relaxed. During the initial lockdown period, COVID-19 was the primary respiratory pathogen detected by multiplex respiratory panels. As COVID-19 containment measures were relaxed, the first non-COVID respiratory viruses to return to prepandemic levels were members of the rhinovirus/enterovirus family. After the complete removal of COVID-19 precautions at the state level, including an end to mask mandates, we observed the robust return of seasonal coronaviruses, parainfluenza virus, and respiratory syncytial virus. Inasmuch as COVID-19 has dominated the landscape of respiratory infections since early 2020, it is important for clinicians to recognize that the return of non-COVID respiratory pathogens may be rapid and significant when COVID-19 containment measures are removed. IMPORTANCE We describe the return of non-COVID respiratory viruses after the removal of COVID-19 mitigation measures. It is important for the public and physicians to recognize that, after months of COVID-19 being the primary driver of respiratory infection, more typical seasonal respiratory illnesses have returned, and this return is out of the normal season for some of these pathogens. Thus, clinicians and the public must now consider both COVID-19 and other respiratory illnesses when a patient presents with symptomatic respiratory illness.
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COVID-19/epidemiología , COVID-19/prevención & control , Control de Enfermedades Transmisibles , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/prevención & control , Infecciones por Coxsackievirus/epidemiología , Infecciones por Coxsackievirus/prevención & control , Enterovirus/aislamiento & purificación , Humanos , Programas Obligatorios/estadística & datos numéricos , Orthomyxoviridae/aislamiento & purificación , Infecciones por Orthomyxoviridae/epidemiología , Infecciones por Orthomyxoviridae/prevención & control , Infecciones por Picornaviridae/epidemiología , Infecciones por Picornaviridae/prevención & control , Rhinovirus/aislamiento & purificación , SARS-CoV-2/crecimiento & desarrollo , Texas/epidemiologíaRESUMEN
BACKGROUND: We assessed performance of participant-collected midturbinate nasal swabs compared to study staff-collected midturbinate nasal swabs for the detection of respiratory viruses among pregnant women in Bangkok, Thailand. METHODS: We enrolled pregnant women aged ≥18 years and followed them throughout the 2018 influenza season. Women with acute respiratory illness self-collected midturbinate nasal swabs at home for influenza viruses, respiratory syncytial viruses (RSV), and human metapneumoviruses (hMPV) real-time RT-PCR testing and the study nurse collected a second midturbinate nasal swab during home visits. Paired specimens were processed and tested on the same day. RESULTS: The majority (109, 60%) of 182 participants were 20-30 years old. All 200 paired swabs had optimal specimen quality. The median time from symptom onsets to participant-collected swabs was 2 days and to staff-collected swabs was also 2 days. The median time interval between the 2 swabs was 2 hours. Compared to staff-collected swabs, the participant-collected swabs were 93% sensitive and 99% specific for influenza virus detection, 94% sensitive and 99% specific for RSV detection, and 100% sensitive and 100% specific for hMPV detection. CONCLUSIONS: Participant-collected midturbinate nasal swabs were a valid alternative approach for laboratory confirmation of influenza-, RSV-, and hMPV-associated illnesses among pregnant women in a community setting.
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Gripe Humana/epidemiología , Metapneumovirus/aislamiento & purificación , Nasofaringe/virología , Orthomyxoviridae/aislamiento & purificación , Infecciones por Paramyxoviridae/epidemiología , Infecciones por Virus Sincitial Respiratorio/epidemiología , Virus Sincitial Respiratorio Humano/aislamiento & purificación , Infecciones del Sistema Respiratorio/virología , Manejo de Especímenes , Adolescente , Adulto , Estudios de Factibilidad , Femenino , Humanos , Gripe Humana/diagnóstico , Embarazo , Mujeres Embarazadas , Tailandia/epidemiología , Adulto JovenRESUMEN
The global damage that a widespread viral infection can cause is evident from the ongoing COVID-19 pandemic. The importance of virus detection to prevent the spread of viruses has been reaffirmed by the pandemic and the associated social and economic damage. Surface plasmon resonance (SPR) in microscale and localized SPR (LSPR) in nanoscale virus sensing systems are thought to be useful as next-generation detection methods. Many studies have been conducted on ultra-sensitive technologies, especially those based on signal amplification. In some cases, it has been reported that even a low viral load can be measured, indicating that the virus can be detected in patients even in the early stages of the viral infection. These findings corroborate that SPR and LSPR are effective in minimizing false-positives and false-negatives that are prevalent in the existing virus detection techniques. In this review, the methods and signal responses of SPR and LSPR-based virus detection technologies are summarized. Furthermore, this review surveys some of the recent developments reported and discusses the limitations of SPR and LSPR-based virus detection as the next-generation detection technologies.
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Nanopartículas del Metal/química , SARS-CoV-2/fisiología , Resonancia por Plasmón de Superficie/métodos , Virión/aislamiento & purificación , COVID-19/diagnóstico , COVID-19/virología , Virus del Dengue/aislamiento & purificación , Virus del Dengue/fisiología , Humanos , Límite de Detección , Orthomyxoviridae/aislamiento & purificación , Orthomyxoviridae/fisiología , Sistemas de Atención de Punto , SARS-CoV-2/aislamiento & purificación , Virión/químicaRESUMEN
Next-generation sequencing is regularly used to identify viral sequences in DNA or RNA samples of infected hosts. A major step of most pipelines for virus detection is to map sequence reads against known virus genomes. Due to small differences between the sequences of related viruses, and due to several biological or technical errors, mapping underlies uncertainties. As a consequence, the resulting list of detected viruses can lack robustness. A new approach for generating artificial sequencing reads together with a strategy of resampling from the original findings is proposed that can help to assess the robustness of the originally identified list of viruses. From the original mapping result in form of a SAM file, a set of statistical distributions are derived. These are used in the resampling pipeline to generate new artificial reads which are again mapped versus the reference genomes. By summarizing the resampling procedure, the analyst receives information about whether the presence of a particular virus in the sample gains or losses evidence, and thus about the robustness of the original mapping list but also that of individual viruses in this list. To judge robustness, several indicators are derived from the resampling procedure such as the correlation between original and resampling read counts, or the statistical detection of outliers in the differences of read counts. Additionally, graphical illustrations of read count shifts via Sankey diagrams are provided. To demonstrate the use of the new approach, the resampling approach is applied to three real-world data samples, one of them with laboratory-confirmed Influenza sequences, and to artificially generated data where virus sequences have been spiked into the sequencing data of a host. By applying the resampling pipeline, several viruses drop from the original list while new viruses emerge, showing robustness of those viruses that remain in the list. The evaluation of the new approach shows that the resampling approach is helpful to analyze the viral content of a biological sample, to rate the robustness of original findings and to better show the overall distribution of findings. The method is also applicable to other virus detection pipelines based on read mapping.
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Orthomyxoviridae/aislamiento & purificación , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Orthomyxoviridae/genéticaRESUMEN
Glycan-targeting antibodies and pseudo-antibodies have been extensively studied for their stoichiometry, avidity, and their interactions with the rapidly modifying glycan shield of influenza A. Broadly neutralizing antiviral agents bind in the same order when they neutralize enveloped viruses regardless of the location of epitopes to the host receptor binding site. Herein, we investigated the binding of cyanovirin-N (CV-N) to surface-expressed glycoproteins such as those of human immunodeficiency virus (HIV) gp120, hemagglutinin (HA), and Ebola (GP)1,2 and compared their binding affinities with the binding response to the trimer-folded gp140 using surface plasmon resonance (SPR). Binding-site knockout variants of an engineered dimeric CV-N molecule (CVN2) revealed a binding affinity that correlated with the number of (high-) affinity binding sites. Binding curves were specific for the interaction with N-linked glycans upon binding with two low-affinity carbohydrate binding sites. This biologically active assembly of a domain-swapped CVN2, or monomeric CV-N, bound to HA with a maximum KD of 2.7 nM. All three envelope spike proteins were recognized at a nanomolar KD, whereas binding to HIV neutralizing 2G12 by targeting HA and Ebola GP1,2 was measured in the µM range and specific for the bivalent binding scheme in SPR. In conclusion, invariant structural protein patterns provide a substrate for affinity maturation in the membrane-anchored HA regions, as well as the glycan shield on the membrane-distal HA top part. They can also induce high-affinity binding in antiviral CV-N to HA at two sites, and CVN2 binding is achieved at low-affinity binding sites.