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1.
MMWR Morb Mortal Wkly Rep ; 69(7): 177-182, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32078591

RESUMO

During the 2019-20 influenza season, influenza-like illness (ILI)* activity first exceeded the national baseline during the week ending November 9, 2019, signaling the earliest start to the influenza season since the 2009 influenza A(H1N1) pandemic. Activity remains elevated as of mid-February 2020. In the United States, annual vaccination against seasonal influenza is recommended for all persons aged ≥6 months (1). During each influenza season, CDC estimates seasonal influenza vaccine effectiveness in preventing laboratory-confirmed influenza associated with medically attended acute respiratory illness (ARI). This interim report used data from 4,112 children and adults enrolled in the U.S. Influenza Vaccine Effectiveness Network (U.S. Flu VE Network) during October 23, 2019-January 25, 2020. Overall, vaccine effectiveness (VE) against any influenza virus associated with medically attended ARI was 45% (95% confidence interval [CI] = 36%-53%). VE was estimated to be 50% (95% CI = 39%-59%) against influenza B/Victoria viruses and 37% (95% CI = 19%-52%) against influenza A(H1N1)pdm09, indicating that vaccine has significantly reduced medical visits associated with influenza so far this season. Notably, vaccination provided substantial protection (VE = 55%; 95% CI = 42%-65%) among children and adolescents aged 6 months-17 years. Interim VE estimates are consistent with those from previous seasons, ranging from 40%-60% when influenza vaccines were antigenically matched to circulating viruses. CDC recommends that health care providers continue to administer influenza vaccine to persons aged ≥6 months because influenza activity is ongoing, and the vaccine can still prevent illness, hospitalization, and death associated with currently circulating influenza viruses as well as other influenza viruses that might circulate later in the season.


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vírus da Influenza B/isolamento & purificação , Vacinas contra Influenza/administração & dosagem , Influenza Humana/prevenção & controle , Vigilância da População , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Vacinas contra Influenza/imunologia , Influenza Humana/epidemiologia , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Estações do Ano , Estados Unidos/epidemiologia , Adulto Jovem
2.
BMC Infect Dis ; 19(1): 964, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31718571

RESUMO

BACKGROUND: The aim of this study was to evaluate the correlation between clinical and imaging findings with a worse clinical outcome in patients with a confirmed diagnosis of H1N1 influenza A virus. METHODS: Patients with a positive viral test for influenza A H1N1 in 2016 and chest radiography (CR) and/or computed tomography (CT) results had clinical and imaging data reviewed. Hospitalization, admission to the intensive care unit or death were defined as worse clinical outcomes. The association between clinical and imaging features and the worse outcome was calculated in a logistical regression model. RESULTS: Eighty of 160 (50%) patients were men, with a mean age of 43 ± 19 years. The most common symptoms were as follows: flu-like symptoms 141/160 (88%), dyspnea (25/160, 17%), and thoracic pain (7/160, 5%). Abnormalities on CR were detected in 8/110 (7%) patients, and 43/59 (73%) patients had an abnormal CT. The following variables were associated with worse clinical outcomes: the presence of diabetes mellitus (DM), hypertension, dyspnea, thoracic pain, abnormal CR or CT regardless of the type of finding, CT with consolidation or ground glass opacity. CONCLUSIONS: The presence of DM, hypertension, dyspnea, thoracic pain, or an abnormal CR or CT on admission were associated with worse clinical outcomes in patients with H1N1 influenza A virus infection. Thus, the use of readily accessible clinical and imaging features on admission may have a role in the evaluation of patients with H1N1 infection.


Assuntos
Influenza Humana/diagnóstico , Adulto , Feminino , Hospitalização , Humanos , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/patologia , Influenza Humana/virologia , Unidades de Terapia Intensiva , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Radiografia Torácica , Estudos Retrospectivos , Índice de Gravidade de Doença , Tórax/diagnóstico por imagem , Tomografia Computadorizada por Raios X
3.
Emerg Microbes Infect ; 8(1): 1535-1545, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31661383

RESUMO

Influenza A virus infections occur in different species, causing mild to severe respiratory symptoms that lead to a heavy disease burden. Eurasian avian-like swine influenza A(H1N1) viruses (EAS-H1N1) are predominant in pigs and occasionally infect humans. An influenza A(H1N1) virus was isolated from a boy who was suffering from fever and headache and designated as A/Tianjin-baodi/1606/2018(H1N1). Full-genome sequencing and phylogenetic analysis revealed that A/Tianjin-baodi/1606/2018(H1N1) is a novel reassortant EAS-H1N1 containing gene segments from EAS-H1N1 (HA and NA), classical swine H1N1(NS) and A(H1N1)pdm09(PB2, PB2, PA, NP and M) viruses. The isolation and analysis of A/Tianjin-baodi/1606/2018(H1) provide further evidence that EAS-H1N1 poses a threat to human health and greater attention should be paid to surveillance of influenza virus infection in pigs and humans.


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/virologia , Infecções por Orthomyxoviridae/veterinária , Vírus Reordenados/isolamento & purificação , Doenças dos Suínos/virologia , Animais , Criança , China , Humanos , Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H1N1/genética , Influenza Aviária/virologia , Masculino , Infecções por Orthomyxoviridae/virologia , Filogenia , Aves Domésticas , Doenças das Aves Domésticas/virologia , Vírus Reordenados/classificação , Vírus Reordenados/genética , Suínos
4.
MMWR Morb Mortal Wkly Rep ; 68(40): 880-884, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31600182

RESUMO

During May 19-September 28, 2019,* low levels of influenza activity were reported in the United States, with cocirculation of influenza A and influenza B viruses. In the Southern Hemisphere seasonal influenza viruses circulated widely, with influenza A(H3) predominating in many regions; however, influenza A(H1N1)pdm09 and influenza B viruses were predominant in some countries. In late September, the World Health Organization (WHO) recommended components for the 2020 Southern Hemisphere influenza vaccine and included an update to the A(H3N2) and B/Victoria-lineage components. Annual influenza vaccination is the best means for preventing influenza illness and its complications, and vaccination before influenza activity increases is optimal. Health care providers should recommend vaccination for all persons aged ≥6 months who do not have contraindications to vaccination (1).


Assuntos
Saúde Global/estatística & dados numéricos , Vacinas contra Influenza/química , Influenza Humana/epidemiologia , Vigilância da População , Farmacorresistência Viral , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vírus da Influenza B/efeitos dos fármacos , Vírus da Influenza B/genética , Vírus da Influenza B/isolamento & purificação , Influenza Humana/virologia , Estações do Ano , Estados Unidos/epidemiologia
5.
Emerg Microbes Infect ; 8(1): 1456-1464, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31603050

RESUMO

Pigs play an important role in interspecies transmission of the influenza virus, particularly as "mixing vessels" for reassortment. Two influenza A/H1N1 virus strains, A/swine/Siberia/1sw/2016 and A/swine/Siberia/4sw/2017, were isolated during a surveillance of pigs from private farms in Russia from 2016 to 2017. There was a 10% identity difference between the HA and NA nucleotide sequences of isolated strains and the most phylogenetically related sequences (human influenza viruses of 1980s). Simultaneously, genome segments encoding internal proteins were found to be phylogenetically related to the A/H1N1pdm09 influenza virus. In addition, two amino acids (129-130) were deleted in the HA of A/swine/Siberia/4sw/2017 compared to that of A/swine/Siberia/1sw/2016 HA.


Assuntos
Vírus da Influenza A Subtipo H1N1/genética , Infecções por Orthomyxoviridae/veterinária , Vírus Reordenados/genética , Doenças dos Suínos/epidemiologia , Suínos/microbiologia , Animais , Genoma Viral , Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Infecções por Orthomyxoviridae/epidemiologia , Filogenia , Vírus Reordenados/isolamento & purificação , Federação Russa/epidemiologia , Doenças dos Suínos/virologia
6.
Int J Infect Dis ; 89: 87-95, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31493523

RESUMO

OBJECTIVES: To evaluate the performance of rapid influenza diagnostic tests (RIDT) and influenza vaccines' effectiveness (VE) during an outbreak setting. METHODS: We compared the performance of a RIDT with RT-PCR for influenza virus detection in influenza-like illness (ILI) patients enrolled during the 2016/17 season in Mexico City. Using the test-negative design, we estimated influenza VE in all participants and stratified by age, virus subtype, and vaccine type (trivalent vs quadrivalent inactivated vaccines). The protective value of some clinical variables was evaluated by regression analyses. RESULTS: We enrolled 592 patients. RT-PCR detected 93 cases of influenza A(H1N1)pdm09, 55 of AH3N2, 141 of B, and 13 A/B virus infections. RIDT showed 90.7% sensitivity and 95.7% specificity for influenza A virus detection, and 91.5% sensitivity and 95.3% specificity for influenza B virus detection. Overall VE was 33.2% (95% CI: 3.0-54.0; p = 0.02) against any laboratory-confirmed influenza infection. VE estimates against influenza B were higher for the quadrivalent vaccine. Immunization and occupational exposure were protective factors against influenza. CONCLUSIONS: The RIDT was useful to detect influenza cases during an outbreak setting. Effectiveness of 2016/17 influenza vaccines administered in Mexico was low but significant. Our data should be considered for future local epidemiological policies.


Assuntos
Vacinas contra Influenza/administração & dosagem , Influenza Humana/diagnóstico , Adolescente , Adulto , Criança , Testes Diagnósticos de Rotina/métodos , Surtos de Doenças , Feminino , Humanos , Imunização , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza B/genética , Vírus da Influenza B/imunologia , Vírus da Influenza B/isolamento & purificação , Vacinas contra Influenza/imunologia , Influenza Humana/epidemiologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Estações do Ano , Vacinação , Adulto Jovem
7.
BMC Infect Dis ; 19(1): 676, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31370782

RESUMO

BACKGROUND: In addition to seasonal influenza viruses recently circulating in humans, avian influenza viruses (AIVs) of H5N1, H5N6 and H7N9 subtypes have also emerged and demonstrated human infection abilities with high mortality rates. Although influenza viral infections are usually diagnosed using viral isolation and serological/molecular analyses, the cost, accessibility, and availability of these methods may limit their utility in various settings. The objective of this study was to develop and optimized a multiplex detection system for most influenza viruses currently infecting humans. METHODS: We developed and optimized a multiplex detection system for most influenza viruses currently infecting humans including two type B (both Victoria lineages and Yamagata lineages), H1N1, H3N2, H5N1, H5N6, and H7N9 using Reverse Transcriptional Loop-mediated Isothermal Amplification (RT-LAMP) technology coupled with a one-pot colorimetric visualization system to facilitate direct determination of results without additional steps. We also evaluated this multiplex RT-LAMP for clinical use using a total of 135 clinical and spiked samples (91 influenza viruses and 44 other human infectious viruses). RESULTS: We achieved rapid detection of seasonal influenza viruses (H1N1, H3N2, and Type B) and avian influenza viruses (H5N1, H5N6, H5N8 and H7N9) within an hour. The assay could detect influenza viruses with high sensitivity (i.e., from 100 to 0.1 viral genome copies), comparable to conventional RT-PCR-based approaches which would typically take several hours and require expensive equipment. This assay was capable of specifically detecting each influenza virus (Type B, H1N1, H3N2, H5N1, H5N6, H5N8 and H7N9) without cross-reactivity with other subtypes of AIVs or other human infectious viruses. Furthermore, 91 clinical and spiked samples confirmed by qRT-PCR were also detected by this multiplex RT-LAMP with 98.9% agreement. It was more sensitive than one-step RT-PCR approach (92.3%). CONCLUSIONS: Results of this study suggest that our multiplex RT-LAMP assay may provide a rapid, sensitive, cost-effective, and reliable diagnostic method for identifying recent influenza viruses infecting humans, especially in locations without access to large platforms or sophisticated equipment.


Assuntos
Colorimetria/métodos , Vírus da Influenza A/genética , Influenza Humana/virologia , Técnicas de Amplificação de Ácido Nucleico/métodos , Reações Cruzadas , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Virus da Influenza A Subtipo H5N1/genética , Subtipo H7N9 do Vírus da Influenza A/genética , Subtipo H7N9 do Vírus da Influenza A/isolamento & purificação , Vírus da Influenza A/isolamento & purificação , Vírus da Influenza A/patogenicidade , Transcrição Reversa
8.
Nat Commun ; 10(1): 3422, 2019 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-31366921

RESUMO

Severe influenza infection has no effective treatment available. One of the key barriers to developing host-directed therapy is a lack of reliable prognostic factors needed to guide such therapy. Here, we use a network analysis approach to identify host factors associated with severe influenza and fatal outcome. In influenza patients with moderate-to-severe diseases, we uncover a complex landscape of immunological pathways, with the main changes occurring in pathways related to circulating neutrophils. Patients with severe disease display excessive neutrophil extracellular traps formation, neutrophil-inflammation and delayed apoptosis, all of which have been associated with fatal outcome in animal models. Excessive neutrophil activation correlates with worsening oxygenation impairment and predicted fatal outcome (AUROC 0.817-0.898). These findings provide new evidence that neutrophil-dominated host response is associated with poor outcomes. Measuring neutrophil-related changes may improve risk stratification and patient selection, a critical first step in developing host-directed immune therapy.


Assuntos
Armadilhas Extracelulares/imunologia , Influenza Humana/imunologia , Influenza Humana/patologia , Ativação de Neutrófilo/imunologia , Neutrófilos/imunologia , Ciclo Celular/imunologia , Feminino , Expressão Gênica/genética , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/imunologia , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vírus da Influenza B/imunologia , Vírus da Influenza B/isolamento & purificação , Influenza Humana/mortalidade , Pulmão/imunologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Respiração Artificial , Insuficiência Respiratória/mortalidade , Insuficiência Respiratória/patologia , Insuficiência Respiratória/virologia
9.
Indian J Med Microbiol ; 37(1): 42-49, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31424009

RESUMO

Introduction: Influenza A(H1N1)pdm09 virus, since its identification in April 2009, has continued to cause significant outbreaks of respiratory tract infections including pandemics in humans. In the course of its evolution, the virus has acquired many mutations with an ability to cause increased disease severity. A regular molecular surveillance of the virus is essential to mark the evolutionary changes that may cause a shift to the viral behavior. Materials and Methods: Samples of Throat/Nasal swabs were collected from a total of 3715 influenza-like illness cases and screened by Real-time Reverse Transcription-Polymerase Chain Reaction for influenza viruses. Nucleotide sequence analysis was done to identify changes in antigenicity of the virus strains. Results: The present study describes the molecular characteristics of influenza A(H1N1)pdm09 viruses detected in Assam of Northeast India during 2009-2015. Influenza A viruses were detected in 11.4% (425/3715), of which influenza A(H1N1)pdm09 viruses were detected in 41.4% (176/425). The nucleotide sequencing of influenza A(H1N1)pdm09 viruses revealed a total of 17 and 22 amino acid substitutions in haemagglutinin (HA) and neuraminidase (NA) genes of the virus, respectively, compared to contemporary vaccine strain A/California/07/2009. The important mutations detected in HA genes of A/Assam(H1N1)pdm09 strains included E391K, K180Q and S202T. Mutation 'N248D' which has an ability to develop oseltamivir resistance was also detected in NA gene of A/Assam(H1N1)pdm09 strains. Conclusions: Regular molecular surveillance of influenza A(H1N1)pdm09 is important to monitor the viral behavior in terms of increase virulence, drug resistance pattern and emergence of novel strains.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H3N2/genética , Influenza Humana/epidemiologia , Neuraminidase/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antivirais/farmacologia , Sequência de Bases , Criança , Pré-Escolar , Feminino , Variação Genética/genética , Humanos , Índia/epidemiologia , Lactente , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Influenza Humana/tratamento farmacológico , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Oseltamivir/farmacologia , Filogenia , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de RNA , Adulto Jovem
11.
Emerg Microbes Infect ; 8(1): 1017-1026, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31287780

RESUMO

Host switch events of influenza A viruses (IAVs) continuously pose a zoonotic threat to humans. In 2013, swine-origin H1N1 IAVs emerged in dogs soon after they were detected in swine in the Guangxi province of China. This host switch was followed by multiple reassortment events between these H1N1 and previously circulating H3N2 canine IAVs (IAVs-C) in dogs. To evaluate the phenotype of these newly identified viruses, we characterized three swine-origin H1N1 IAVs-C and one reassortant H1N1 IAV-C. We found that H1N1 IAVs-C predominantly bound to human-type receptors, efficiently transmitted via direct contact in guinea pigs and replicated in human lung cells. Moreover, the swine-origin H1N1 IAVs-C were lethal in mice and were transmissible by respiratory droplets in guinea pigs. Importantly, sporadic human infections with these viruses have been detected, and preexisting immunity in humans might not be sufficient to prevent infections with these new viruses. Our results show the potential of H1N1 IAVs-C to infect and transmit in humans, suggesting that these viruses should be closely monitored in the future.


Assuntos
Doenças do Cão/virologia , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Infecções por Orthomyxoviridae/veterinária , Doenças dos Suínos/virologia , Animais , China , Doenças do Cão/mortalidade , Cães , Feminino , Cobaias , Humanos , Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/patogenicidade , Vírus da Influenza A Subtipo H3N2/classificação , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Influenza Humana/mortalidade , Influenza Humana/virologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/mortalidade , Infecções por Orthomyxoviridae/virologia , Vírus Reordenados/classificação , Vírus Reordenados/genética , Vírus Reordenados/isolamento & purificação , Vírus Reordenados/patogenicidade , Suínos , Doenças dos Suínos/mortalidade , Virulência
12.
BMC Infect Dis ; 19(1): 668, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31357951

RESUMO

BACKGROUND: A severe seasonal influenza epidemic was observed during 2017-2018 in China, prompting questions on clinical characteristics and outcomes of severe cases with influenza. METHODS: We retrospectively collected clinical data and outcomes of laboratory-confirmed hospitalized patients (severe to critical) during Jan-2011 to Feb-2018 from five hospitals, followed by a systematic analysis of cases from 2017 to 2018 (n = 289) and all previous epidemics during 2011-2017 (n = 169). RESULTS: In-hospital fatality was over 5-folds higher during the 2017-2018 (p < 0.01) in which 19 patients died (6.6%), whereas only 2 mortalities (1.2%) were observed during 2011-2017. Of the 289 hospitalized in 2017-2018, 153 were confirmed with influenza B virus, 110 with A/H1N1pdm09, and 26 A/H3N2, whereas A/H1N1pdm09 was the predominant cause of hospitalization in previous seasons combined (45%). Fatal cases in 2017-2018 were exclusively associated with either influenza B or A/H1N1pdm09. Our results show that a significant lower proportion of patients aged 14 or greater were treated with oseltamivir, during the 2017-2018 epidemic, and exhibited higher levels of clinical severity. CONCLUSIONS: In-hospital fatality rate might be significantly higher in the 2017-2018 season in China. A sufficient supply of oseltamivir and antiviral therapy within 48 h from onset could reduce fatality rates.


Assuntos
Antivirais/uso terapêutico , Epidemias , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vírus da Influenza B/isolamento & purificação , Influenza Humana/epidemiologia , Oseltamivir/uso terapêutico , Adolescente , Adulto , China/epidemiologia , Feminino , Hospitalização , Humanos , Influenza Humana/mortalidade , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
13.
J Vet Med Sci ; 81(9): 1341-1347, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31341136

RESUMO

Influenza virus is known to affect wild felids. To explore the prevalence of influenza viruses in these animal species, 196 archival sera from 5 felid species including Panthera tigris (N=147), Prionailurus viverrinus (N=35), Panthera leo (N=5), Pardofelis temminckii (N=8) and Neofelis nebulosa (N=1) collected between 2011 and 2015 in 10 provinces of Thailand were determined for the presence of antibody to avian and human influenza viruses. Blocking enzyme-linked immunosorbent (ELISA) assay and hemagglutination inhibition (HI) assay were employed as the screening tests, which the serum samples with HI antibody titers ≥20 were further confirmed by cytopathic effect/hemagglutination based-microneutralization (CPE/HA-based microNT) test. Based on HI and microNT assays, the seropositive rates of low pathogenic avian influenza (LPAI) H5 virus, highly pathogenic avian influenza (HPAI) H5 virus and human H1 virus were 1.53% (3/196), 2.04% (4/196) and 6.63% (13/196), respectively. In addition, we also found antibody against both LPAI H5 virus and HPAI H5 virus in 2 out of 196 tested sera (1.02%). Evidences of influenza virus infection were found in captive P. tigris in Kanchanaburi, Nakhon Sawan and Ratchaburi provinces of Thailand. The findings of our study highlights the need of a continuous active surveillance program of influenza viruses in wild felid species.


Assuntos
Felidae/virologia , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Virus da Influenza A Subtipo H5N1/isolamento & purificação , Infecções por Orthomyxoviridae/veterinária , Animais , Animais de Zoológico/virologia , Anticorpos Antivirais/sangue , Ensaio de Imunoadsorção Enzimática/veterinária , Testes de Inibição da Hemaglutinação/veterinária , Infecções por Orthomyxoviridae/epidemiologia , Prevalência , Estudos Soroepidemiológicos , Tailândia/epidemiologia
14.
Adv Exp Med Biol ; 1222: 63-68, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31352577

RESUMO

The SENTINEL influenza surveillance system is an important tool for monitoring influenza in Poland. Data from this system are necessary to determine the dynamics of seasonal infections and to announce the epidemic by the country level. For the 2017/18 epidemic season, the dominance of influenza type B was recorded and the highest percentage of infections was recorded in the age group 45-64 years. Among the subtypes of influenza type A, A/H1N1/pdm09 was the predominated subtype. Most cases were reported in the age group of 26-44 and 0-4 years. The influenza virus frequently undergoes modifications. Therefore, it is necessary to constantly monitor the emerging strains around the world.


Assuntos
Epidemias , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza B/isolamento & purificação , Influenza Humana/epidemiologia , Vigilância de Evento Sentinela , Adolescente , Adulto , Distribuição por Idade , Idoso , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza B/genética , Pessoa de Meia-Idade , Polônia/epidemiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estações do Ano , Adulto Jovem
15.
MMWR Morb Mortal Wkly Rep ; 68(24): 544-551, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31220057

RESUMO

Influenza activity* in the United States during the 2018-19 season (September 30, 2018-May 18, 2019) was of moderate severity (1). Nationally, influenza-like illness (ILI)† activity began increasing in November, peaked during mid-February, and returned to below baseline in mid-April; the season lasted 21 weeks,§ making it the longest season in 10 years. Illness attributed to influenza A viruses predominated, with very little influenza B activity. Two waves of influenza A were notable during this extended season: influenza A(H1N1)pdm09 viruses from October 2018 to mid-February 2019 and influenza A(H3N2) viruses from February through May 2019. Compared with the 2017-18 influenza season, rates of hospitalization this season were lower for adults, but were similar for children. Although influenza activity is currently below surveillance baselines, testing for seasonal influenza viruses and monitoring for novel influenza A virus infections should continue year-round. Receiving a seasonal influenza vaccine each year remains the best way to protect against seasonal influenza and its potentially severe consequences.


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vírus da Influenza B/isolamento & purificação , Influenza Humana/epidemiologia , Vigilância da População , Adolescente , Adulto , Idoso , Antivirais/farmacologia , Criança , Mortalidade da Criança , Pré-Escolar , Efeitos Psicossociais da Doença , Farmacorresistência Viral , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza B/efeitos dos fármacos , Vírus da Influenza B/genética , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/química , Influenza Humana/mortalidade , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Pessoa de Meia-Idade , Pacientes Ambulatoriais/estatística & dados numéricos , Pneumonia/mortalidade , Estações do Ano , Índice de Gravidade de Doença , Estados Unidos/epidemiologia , Adulto Jovem
16.
Virology ; 534: 96-107, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31226666

RESUMO

Nasal wash samples from 15 human volunteers challenged with GMP manufactured influenza A/California/04/2009(H1N1) and from 5 naturally infected influenza patients of the 2009 pandemic were deep sequenced using viral targeted hybridization enrichment. Ten single nucleotide polymorphism (SNP) positions were found in the challenge virus. Some of the nonsynonymous changes in the inoculant virus were maintained in some challenge participants, but not in others, indicating that virus is evolving away from the Vero cell adapted inoculant, for example SNPs in the neuraminidase. Many SNP sites in challenge patients and naturally infected patients were found, many not identified previously. The SNPs identified, and phylogenetic analyses, showed that intrahost evolution of the virus are different in challenge participants and naturally infected patients. This study, using hybridization enrichment without PCR, provided an accurate and unbiased assessment of differential intrahost viral evolution from a uniform influenza inoculant in humans and comparison to naturally infected patients.


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/virologia , Adolescente , Adulto , Feminino , Voluntários Saudáveis , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H1N1/genética , Masculino , Pessoa de Meia-Idade , Filogenia , Polimorfismo de Nucleotídeo Único , Proteínas Virais/genética , Adulto Jovem
17.
PLoS Med ; 16(6): e1002829, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31246954

RESUMO

BACKGROUND: Measures of the contribution of influenza to Streptococcus pneumoniae infections, both in the seasonal and pandemic setting, are needed to predict the burden of secondary bacterial infections in future pandemics to inform stockpiling. The magnitude of the interaction between these two pathogens has been difficult to quantify because both infections are mainly clinically diagnosed based on signs and symptoms; a combined viral-bacterial testing is rarely performed in routine clinical practice; and surveillance data suffer from confounding problems common to all ecological studies. We proposed a novel multivariate model for age-stratified disease incidence, incorporating contact patterns and estimating disease transmission within and across groups. METHODS AND FINDINGS: We used surveillance data from England over the years 2009 to 2017. Influenza infections were identified through the virological testing of samples taken from patients diagnosed with influenza-like illness (ILI) within the sentinel scheme run by the Royal College of General Practitioners (RCGP). Invasive pneumococcal disease (IPD) cases were routinely reported to Public Health England (PHE) by all the microbiology laboratories included in the national surveillance system. IPD counts at week t, conditional on the previous time point t-1, were assumed to be negative binomially distributed. Influenza counts were linearly included in the model for the mean IPD counts along with an endemic component describing some seasonal background and an autoregressive component mimicking pneumococcal transmission. Using age-specific counts, Akaike information criterion (AIC)-based model selection suggested that the best fit was obtained when the endemic component was expressed as a function of observed temperature and rainfall. Pneumococcal transmission within the same age group was estimated to explain 33.0% (confidence interval [CI] 24.9%-39.9%) of new cases in the elderly, whereas 50.7% (CI 38.8%-63.2%) of incidence in adults aged 15-44 years was attributed to transmission from another age group. The contribution of influenza on IPD during the 2009 pandemic also appeared to vary greatly across subgroups, being highest in school-age children and adults (18.3%, CI 9.4%-28.2%, and 6.07%, CI 2.83%-9.76%, respectively). Other viral infections, such as respiratory syncytial virus (RSV) and rhinovirus, also seemed to have an impact on IPD: RSV contributed 1.87% (CI 0.89%-3.08%) to pneumococcal infections in the 65+ group, whereas 2.14% (CI 0.87%-3.57%) of cases in the group of 45- to 64-year-olds were attributed to rhinovirus. The validity of this modelling strategy relies on the assumption that viral surveillance adequately represents the true incidence of influenza in the population, whereas the small numbers of IPD cases observed in the younger age groups led to significant uncertainty around some parameter estimates. CONCLUSIONS: Our estimates suggested that a pandemic wave of influenza A/H1N1 with comparable severity to the 2009 pandemic could have a modest impact on school-age children and adults in terms of IPD and a small to negligible impact on infants and the elderly. The seasonal impact of other viruses such as RSV and rhinovirus was instead more important in the older population groups.


Assuntos
Análise de Dados , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/epidemiologia , Análise de Séries Temporais Interrompida/tendências , Infecções Pneumocócicas/epidemiologia , Vigilância da População , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/diagnóstico , Masculino , Pessoa de Meia-Idade , Infecções Pneumocócicas/diagnóstico , Vigilância da População/métodos , Adulto Jovem
18.
J Coll Physicians Surg Pak ; 29(5): 459-462, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31036119

RESUMO

OBJECTIVE: To determine the frequency of infections caused by Influenza viruses, i.e. Influenza A (H1N1) pdm09, Influenza A (H3N2) and Influenza B in patients presenting with respiratory tract infections, i.e. influenza-like illness (ILI) and severe acute respiratory illness (SARI). STUDY DESIGN: Descriptive, cross-sectional study. PLACE AND DURATION OF STUDY: Department of Virology, Armed Forces Institute of Pathology (AFIP), Rawalpindi, from October 2017 to February 2018. METHODOLOGY: A total of 624 samples from patients with respiratory tract infections (both ILI and SARI) were included in the study. Specimens collected from the patients included nasal swabs and throat swabs, which were transported in viral transport medium (VTM) to Virology Department, AFIP. Multiplex PCR was done for Influenza A (H1N1) pdm09, Influenza A (H3N2) and Influenza B. RESULTS: A total of 200 (32%) samples were found to be positive for Influenza viruses. Out of total 624 samples analysed, 220 (35.3%) were from females and 404 (64.7%) from males. Among these, 510 (81.7%) presented with ILI and 114 (18.3%) with SARI. Among positive samples, 120 (19.2%) samples were positive for H1N1, 61 (9.8%) for H3N2 and 19 (3%) were positive for Influenza B. Highest number of positive cases occurred in the month of January, i.e. 148 (74%) cases. Only 3 (2.5%) patients out of 120 infected with H1N1 were in age group-I (0-5 years). While in age group-II (6-30 years), age group-III (31-60 years), and age group-IV (>60 years); 39 (32.5%), 63 (52.5%) and 15 (12.5%) patients were infected by H1N1, respectively. Maximum patients with H3N2 infection were in age group-III; 30 (49.2%) of the total 61. Commonest Influenza subtype in age group-IV was H3N2 found in 20 (32.8%) patients, followed by H1N1 in 15 (12.5%) patients. CONCLUSION: The dominant subtype in our set-up, during winter of 2017-2018, was Influenza A (H1N1) pdm09. Highest numbers of positive cases were recorded in the month of January. People with ILI and SARI should be tested for Influenza viruses to avoid unnecessary use of antibiotics.


Assuntos
Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza B/genética , Influenza Humana/diagnóstico , Reação em Cadeia da Polimerase Multiplex/métodos , Infecções Respiratórias/diagnóstico , Síndrome Respiratória Aguda Grave/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vírus da Influenza B/isolamento & purificação , Influenza Humana/epidemiologia , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Estações do Ano , Síndrome Respiratória Aguda Grave/epidemiologia , Síndrome Respiratória Aguda Grave/virologia , Adulto Jovem
19.
Eur J Clin Microbiol Infect Dis ; 38(7): 1307-1312, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31069558

RESUMO

Surveillance of influenza epidemics is a priority for risk assessment and pandemic preparedness, yet representation of their spatiotemporal intensity remains limited. Using the epidemic of influenza type A in 2016 in Australia, we demonstrated a simple but statistically sound adaptive method of mapping epidemic evolution over space and time. Weekly counts of persons with laboratory confirmed influenza type A infections in Australia in 2016 were analysed by official national statistical region. Weekly standardised epidemic intensity was represented by a standard score (z-score) calculated using the standard deviation of below-median counts in the previous 52 weeks. A geographic information system (GIS) was used to present the epidemic progression. There were 79,628 notifications of influenza A infections included. Of these, 79,218 (99.5%) were allocated to a geographical area. The GIS maps indicated areas of elevated epidemic intensity across Australia by week and area that were consistent with the observed start, peak and decline of the epidemic when compared with counts aggregated at the state and territory level. This simple, adaptable approach could improve local level epidemic intelligence in a variety of settings and for other diseases. It may also facilitate increased understanding of geographic epidemic dynamics.


Assuntos
Epidemias/estatística & dados numéricos , Monitoramento Epidemiológico , Influenza Humana/epidemiologia , Pandemias/estatística & dados numéricos , Análise Espaço-Temporal , Austrália/epidemiologia , Técnicas de Laboratório Clínico , Interpretação Estatística de Dados , Progressão da Doença , Sistemas de Informação Geográfica , Geografia , Humanos , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/diagnóstico , Análise de Regressão , Medição de Risco
20.
ACS Appl Mater Interfaces ; 11(21): 19495-19505, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31058488

RESUMO

Rapid and early diagnosis of respiratory viruses is key to preventing infections from spreading and guiding treatments. Here, we developed a sensitive and quantitative surface-enhanced Raman scattering-based lateral flow immunoassay (SERS-based LFIA) strip for simultaneous detection of influenza A H1N1 virus and human adenovirus (HAdV) by using Fe3O4@Ag nanoparticles as magnetic SERS nanotags. The new type of Fe3O4@Ag magnetic tags, which were conjugated with dual-layer Raman dye molecules and target virus-capture antibodies, performs the following functions: specific recognition and magnetic enrichment of target viruses in the solution and SERS detection of the viruses on the strip. Based on this strategy, the magnetic SERS strip can directly be used for real biological samples without any sample pretreatment steps. The limits of detection for H1N1 and HAdV were 50 and 10 pfu/mL, respectively, which were 2000 times more sensitive than those from the standard colloidal gold strip method. Moreover, the proposed strip is easy to operate, rapid, stable, and can achieve high throughput and is thus a potential tool for early detection of virus infection.


Assuntos
Adenovírus Humanos/isolamento & purificação , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Magnetismo , Análise Espectral Raman , Anticorpos/metabolismo , Coloides/química , Compostos Férricos/química , Ouro/química , Humanos , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/ultraestrutura , Sensibilidade e Especificidade , Prata/química
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