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2.
Qual Health Res ; 33(14): 1291-1304, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37846588

RESUMO

During the COVID-19 pandemic, the need to triage COVID-19 patients in ICUs emerged globally. Triage guidelines were established in many countries; however, the actual triage decision-making processes and decisions themselves made by frontline medical providers may not have exactly reflected those guidelines. Despite the need to understand decisions and processes in practice regarding patient ICU admission and mechanical ventilator usage to identify areas of improvement for medical care provision, such research is limited. This qualitative study was conducted to identify the decision-making processes regarding COVID-19 patient ICU admissions and mechanical ventilator allocation by frontline medical providers and issues associated with those processes in an ICU during the COVID-19 pandemic. Semi-structured, in-depth interviews were conducted with ICU physicians and nurses working at an urban tertiary referral hospital in Japan between February and April 2022. Patient characteristics that influenced triage decisions made by physicians and the interaction between physicians, nurses, and senior management staff upon making such decisions are discussed in this article. An implicated issue was the lack of legal support for Japanese physicians to practice withdrawal of life-sustaining treatments even during emergencies. Another issue was the impact of non-clinical forces-likely specific to health emergencies-on physicians' decisions regarding mechanical ventilator allocation, where such forces imposed a significant mental burden on the medical providers. We consider public policy and legal implications for future pandemics.


Assuntos
COVID-19 , Humanos , Emergências , Unidades de Terapia Intensiva , Pandemias , Admissão do Paciente , Ventiladores Mecânicos , Japão
3.
BMC Infect Dis ; 22(1): 313, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35354368

RESUMO

BACKGROUND: Lower respiratory tract infection (LRTI) is an important cause of morbidity and mortality in infants and young children. However, the etiological role of viruses and the timing of developing LRTI are not well defined. METHODS: We analyzed the data of a prospective cohort study in the Philippines as a birth cohort. We detected LRTI among children who visited healthcare facilities with respiratory symptom, and collected nasopharyngeal swabs for virus detection. We analyzed the incidence rates (IRs) and cumulative proportion of LRTI and severe LRTI by age group and each virus detected. RESULTS: A total of 350 LRTI episodes were observed from 473 child-years yielded from 419 children. The IRs of LRTI were 70.8, 70.7, and 80.8 per 100 child-years for 0-5, 6-11, and 12-23 months of age, respectively. By 12 months of age, 45% of children developed LRTI at least once. Rhinovirus and respiratory syncytial virus were the most frequently detected viruses in all age groups. However, the IRs of influenza virus were low especially at 0-5 months of age. CONCLUSIONS: We identified various patterns of age-specific IRs of LRTI and severe LRTI for different viruses, which should be considered to establish more effective interventions including vaccinations.


Assuntos
Vírus Sincicial Respiratório Humano , Infecções Respiratórias , Coorte de Nascimento , Pré-Escolar , Humanos , Incidência , Lactente , Filipinas/epidemiologia , Estudos Prospectivos , Infecções Respiratórias/epidemiologia , Vírus Satélites
4.
J Infect Chemother ; 28(7): 1001-1004, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35430092

RESUMO

A concern has been raised that the persistent COVID-19 infection in an immunocompromised host can be the source of the SARS-CoV-2 variants. This is the case of a 61-year-old man in complete remission of a follicular lymphoma after six cycles of rituximab and bendamustine with additional two cycles of rituximab completed eight months prior to the episode of COVID-19 pneumonia. The patient's respiratory failure was long-lasting, and required mechanical ventilation until day 75. Acquired immunity tested negative throughout the observational period. The viral RNA was detectable until day 100 while the infectious virus was isolated until day 79. Seven haplotypes were identified and the non-synonymous mutations accumulated in the spike gene which included E484Q and S494P. In the management of COVID-19 cases with suppressed immune statuses, initial evaluation of existing immunity and monitoring for infectiousness throughout the clinical course including the convalescent stage may be necessary.


Assuntos
COVID-19 , SARS-CoV-2 , Haplótipos , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Rituximab/uso terapêutico , SARS-CoV-2/genética
5.
J Infect Chemother ; 28(1): 41-46, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34635449

RESUMO

INTRODUCTION: In response to global outbreaks of infectious diseases, the need for support from organizations such as the World Health Organization Global Outbreak Alert and Response Network (GOARN) is increasing. Identifying the obstacles and support needs for applicants could increase GOARN deployments from Japan. METHODS: This cross-sectional study involved a web-based, self-administered questionnaire survey targeting Japanese participants in the GOARN Tier 1.5 training workshop, held in Tokyo in December 2019. RESULTS: All 47 Japanese participants in the workshop responded to the survey. Most responders were male and in their 30s and 40s. Participants specialized in case management (42.6%), infection prevention and control (25.6%), epidemiology and surveillance (19.1%). Only two participants (4.6%) had experienced a GOARN deployment. Their motivations for joining the GOARN training workshop were "Desire to be part of an international emerging infectious disease response team" (44.6%), "Interest in making an international contribution" (19.1%), and "Interest in working for the Japanese government in the field of international infectious diseases" (14.9%). Obstacles to GOARN deployments were "Making time for deployments" (45.7%) and "Lack of required professional skills and knowledge" (40.4%). The support needs for GOARN deployments constituted "Periodic simulation training" (51.1%), "Financial support during deployments" (44.7%), and "Technical support for deployments" (40.4%). CONCLUSIONS: Our study revealed the obstacles and support needs of Japanese candidates for GOARN deployment. Making time and upskilling for GOARN deployment were the main obstacles. More practical training (like GOARN Tier 2.0) with other supports are needed. The national framework is desirable to realize these supports.


Assuntos
Doenças Transmissíveis Emergentes , Estudos Transversais , Surtos de Doenças , Saúde Global , Humanos , Japão/epidemiologia , Masculino , Recursos Humanos
6.
Emerg Infect Dis ; 27(3): 915-918, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33622475

RESUMO

The overall coronavirus disease secondary attack rate (SAR) in family members was 19.0% in 10 prefectures of Japan during February 22-May 31, 2020. The SAR was lower for primary cases diagnosed early, within 2 days after symptom onset. The SAR of asymptomatic primary cases was 11.8%.


Assuntos
COVID-19/epidemiologia , Família , Infecções Assintomáticas/epidemiologia , COVID-19/diagnóstico , COVID-19/transmissão , Busca de Comunicante/estatística & dados numéricos , Feminino , Humanos , Incidência , Japão/epidemiologia , Masculino , SARS-CoV-2/isolamento & purificação , Fatores de Tempo
7.
Emerg Infect Dis ; 27(10): 1-9, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34546168

RESUMO

To deal with the risk of emerging diseases with many unknowns, close and timely collaboration and communication between science experts and policymakers are crucial to developing and implementing an effective science-based intervention strategy. The Expert Meeting, an ad hoc medical advisory body, was established in February 2020 to advise Japan's COVID-19 Response Headquarters. The group played an important role in the policymaking process, promoting timely situation awareness and developing science-based proposals on interventions that were promptly reflected in government actions. However, this expert group may have been overly proactive in taking on the government's role in crisis management. For the next stage of managing the coronavirus disease pandemic and future pandemics, the respective roles of the government and its advisory bodies need to be clearly defined. Leadership and strategic risk communication by the government are key.


Assuntos
COVID-19 , Governo , Humanos , Japão/epidemiologia , Pandemias , SARS-CoV-2
8.
Am J Epidemiol ; 190(12): 2536-2543, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34216204

RESUMO

Respiratory syncytial virus (RSV) is a leading cause of lower respiratory tract infection worldwide, but reports of temporal changes in the risk of transmission among close contacts has been scarce. This study aimed to examine an association between the viral load trajectory and transmission risk to develop a better control strategy for the disease spread. We conducted a household-based prospective cohort study in Biliran Province, the Philippines, and enrolled 451 participants to observe the development of acute respiratory infection. Including the cases found at the health-care facility, we analyzed the data of viral loads with symptom records obtained from 172 followed participants who had household member positive for RSV with a rapid test during an RSV outbreak in 2018-2019. We developed a model estimating a temporal change in the viral shedding from the infection and evaluated transmission dynamics. We found that most transmission events occurred within approximately 7 days of the household exposure, including potential presymptomatic transmissions. The inferred risk of infection among those younger than 5 years was 3.5 times higher than that of those older than 5 years. This finding suggested that the initial week after the household exposure is particularly important for preventing RSV spread.


Assuntos
Características da Família , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/transmissão , Carga Viral/fisiologia , Eliminação de Partículas Virais/fisiologia , Fatores Etários , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Modelos Teóricos , Filipinas/epidemiologia , Estudos Prospectivos
9.
Pediatr Res ; 89(7): 1664-1672, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33510411

RESUMO

BACKGROUND: The limited treatment options for children with severe respiratory syncytial virus (RSV) infection highlights the need for a comprehensive understanding of the host cellular response during infection. We aimed to identify host genes that are associated with severe RSV disease and to identify drugs that can be repurposed for the treatment of severe RSV infection. METHODS: We examined clinical data and blood samples from 37 hospitalized children (29 mild and 8 severe) with RSV infection. We tested RNA from blood samples using next-generation sequencing to profile global mRNA expression and identify cellular processes. RESULTS: Retractions, decreased breath sounds, and tachypnea were associated with disease severity. We observed upregulation of genes related to neutrophil, inflammatory response, blood coagulation, and downregulation of genes related to T cell response in children with severe RSV. Using network-based approach, 43 drugs were identified that are predicted to interact with the gene products of these differentially expressed genes. CONCLUSIONS: These results suggest that the changes in the expression pattern in the innate and adaptive immune responses may be associated with RSV clinical severity. Compounds that target these cellular processes can be repositioned as candidate drugs in the treatment of severe RSV. IMPACT: Neutrophil, inflammation, and blood coagulation genes are upregulated in children with severe RSV infection. Expression of T cell response genes are suppressed in cases of severe RSV. Genes identified in this study can contribute in understanding the pathogenesis of RSV disease severity. Drugs that target cellular processes associated with severe RSV can be repositioned as potential therapeutic options.


Assuntos
Infecções por Vírus Respiratório Sincicial/genética , Infecções por Vírus Respiratório Sincicial/patologia , Índice de Gravidade de Doença , Pré-Escolar , Feminino , Predisposição Genética para Doença , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos , Infecções por Vírus Respiratório Sincicial/imunologia , Vírus Sincicial Respiratório Humano/genética
11.
Appl Environ Microbiol ; 86(2)2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31704681

RESUMO

This study aimed to evaluate the prevalence and genetic characteristics of carbapenemase-producing Enterobacteriaceae (CPE) in hospital sewage and river water in the Philippines, which has a typical tropical maritime climate. We collected 83 water samples from 7 hospital sewage and 10 river water sites. CPE were identified using CHROMagar mSuperCARBA, and Gram-negative strains were identified using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) or 16S rRNA gene sequencing. Resistance genes in Enterobacteriaceae strains were identified using PCR and DNA sequencing, and transferability of carbapenemase genes from the CPE was investigated with conjugation experiments. Genotyping was performed using multilocus sequence typing (MLST) for Escherichia coli and Klebsiella pneumoniae Out of 124 Enterobacteriaceae isolates, we identified 51 strains as CPE and divided these into 7 species, 11 E. coli, 14 Klebsiella spp., 15 Enterobacter spp., and 11 others, including 4 additional species. Conjugation experiments via broth mating and using E. coli J53 revealed that 24 isolates can transfer carbapenemase-encoding plasmids. MLST analysis showed that 6 of 11 E. coli isolates belonged to clonal complex 10 (CC10). Of 11 K. pneumoniae strains, 9 unique sequence types (STs) were identified, including ST147. Five types of carbapenemase genes were identified, with the most prevalent being NDM (n = 39), which is epidemic in clinical settings in the Philippines. E. coli CC10 and K. pneumoniae ST147, which are often detected in clinical settings, were the dominant strains. In summary, our results indicate that hospital sewage and river water are contaminated by CPE strains belonging to clinically important clonal groups.IMPORTANCE Carbapenemase-producing Enterobacteriaceae (CPE) cause severe health care-associated infections, and their increasing prevalence is a serious concern. Recently, natural ecosystems have been recognized as important reservoirs of antibiotic resistance genes. We investigated the prevalence and genetic characteristics of CPE isolated from the environment (hospital sewage and river water) in the Philippines and found several CPE, including Escherichia coli and other species, with different carbapenemases. The most prevalent carbapenemase gene type was NDM, which is endemic in clinical settings. This study revealed that isolates belonging to carbapenemase-producing E. coli CC10 and K. pneumoniae sequence type 147 (ST147), which are often detected in clinical settings, were dominant in the natural environment. Our work here provides a report on the presence and characteristics of CPE in the environment in the Philippines and demonstrates that both hospital sewage and river water are contaminated by CPE strains belonging to clinically important clonal groups.


Assuntos
Proteínas de Bactérias/metabolismo , Enterobacteriaceae/isolamento & purificação , Hospitais , Águas Residuárias/microbiologia , beta-Lactamases/metabolismo , Enterobacteriaceae/genética , Tipagem de Sequências Multilocus , Filipinas , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Rios/microbiologia , Análise de Sequência de RNA , Esgotos/microbiologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
12.
J Infect Dis ; 219(2): 197-205, 2019 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-30189092

RESUMO

Background: Acute respiratory infection (ARI) is of great concern in public health. It remains unclear whether viral infections can affect the host's susceptibility to subsequent ARIs. Methods: A prospective cohort study on ARIs of children below 5 years old was conducted in the Philippines from 2014 to 2016. The respiratory symptoms were recorded daily, and nasopharyngeal swabs were collected at both household and health facilities. The specimens were tested for respiratory viruses. We then determined whether viral etiology was associated with the severity of the present ARI and whether previous viral infections was associated with subsequent ARIs. Results: A total of 3851 children and 16337 ARI episodes were enrolled and recorded, respectively. Samples were collected from 24% of all ARI episodes; collection rate at the healthcare facilities was 95%. Enterovirus D68, rhinovirus species C, and respiratory syncytial virus were significantly associated with severe ARIs. The risk for subsequent ARIs was significantly enhanced after infections with adenovirus, influenza A virus, parainfluenza virus type 4, and rhinovirus species C. Conclusions: This study revealed that viral etiology plays a significant role in the severity of the present ARI and that viral infection affects the host's susceptibility to subsequent ARIs.


Assuntos
Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Viroses/epidemiologia , Viroses/etiologia , Viroses/virologia , Pré-Escolar , Enterovirus/patogenicidade , Características da Família , Feminino , Instalações de Saúde , Humanos , Lactente , Recém-Nascido , Vírus da Influenza A , Masculino , Vírus da Parainfluenza 4 Humana , Filipinas/epidemiologia , Estudos Prospectivos , Vírus Sinciciais Respiratórios , Rhinovirus/patogenicidade , Fatores de Risco
13.
J Med Virol ; 91(6): 986-996, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30698827

RESUMO

A prospective matched case-control study was conducted to evaluate associations between dietary histories, including consumption of bivalves, diarrhea, and norovirus positive diarrhea in adult ambulatory patients at an outpatient clinic of a hospital in Tokyo, Japan. Ambulatory cases with diarrhea were matched with nondiarrheal control patients, who visited the same clinic. A standardized questionnaire was used to obtain patients' information, including histories of food consumption and clinical information. Norovirus infection was confirmed using real-time reverse transcription polymerase chain reaction. A total of 207 patients, including 69 diarrheal cases and 138 nondiarrheal cases were included in the analysis. Among them, 60 (29.0%) participants reported consuming bivalves. Norovirus was detected in 35% (24/69) of diarrheal cases. Of those, 10 (41.7%) reported consumption of bivalves and of those, 6 (60.0%) consumed raw bivalves. The proportion of those who consumed raw bivalves was significantly higher in norovirus-positive diarrheal cases than in norovirus-negative diarrheal cases (25.0% vs 6.7%; odds ratio [OR], 4.67; 95% confidence interval [CI], 1.1-20.7) and matched nondiarrheal controls (25.0% vs 6.3%, OR: 5.00; 95% CI, 1.1-22.2). The attributable fraction of consuming raw bivalves for norovirus-associated diarrhea to matched nondiarrheal controls was 20.0%. Consuming raw bivalves was substantially attributed to norovirus-associated diarrhea in adult ambulatory patients and preventive measures for reducing the risk associated with consumption of raw bivalves could decrease the incidence of norovirus-associated diarrhea.


Assuntos
Bivalves/virologia , Infecções por Caliciviridae/etiologia , Diarreia/virologia , Doenças Transmitidas por Alimentos/complicações , Gastroenterite/virologia , Alimentos Marinhos/virologia , Doença Aguda/epidemiologia , Adulto , Animais , Infecções por Caliciviridae/epidemiologia , Estudos de Casos e Controles , Diarreia/epidemiologia , Dieta/efeitos adversos , Fezes/virologia , Feminino , Doenças Transmitidas por Alimentos/epidemiologia , Gastroenterite/epidemiologia , Humanos , Incidência , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Norovirus/isolamento & purificação , Razão de Chances , Estudos Prospectivos , Inquéritos e Questionários , Tóquio/epidemiologia
14.
J Med Virol ; 91(2): 215-224, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29995327

RESUMO

Norovirus (NoV) and sapovirus (SaV) are recognized as the causative agents of acute gastroenteritis, and NoV is one of the leading pathogens reported worldwide. This study reports on the distribution of NoV and SaV genotypes in children hospitalized with acute gastroenteritis in Chiang Mai, Thailand, from January 2015 to February 2017. From a total of 843 stool samples, 170 (20.2%) and 16 (1.9%) were identified as having NoV and SaV infections, respectively. Two samples (0.2%) were positive for both NoV and SaV. Of these, NoV GII.4 (57.2%) was the dominant genotype, followed by GII.2, GII.3, GII.17, GII.6, GII.7, GII.13, GII.14, GII.15, GII.21, GI.6, and GI.5. Among the NoV GII.4 variants, Sydney 2012 was the dominant variant during the period 2015-2016, while the other variants detected in this study were Asia 2003 and New Orleans 2009. Interestingly, an increase of NoV GII.2 was observed in 2016 and 2017. Characterization of partial RNA-dependent RNA polymerase and VP1 nucleotide sequences of GII.2 strains revealed that more than half of the GII.2 strains circulating in 2016 and 2017 were recombinant strains of GII.P16/GII.2. For SaV, the majority of strains belonged to GI.1 (55.6%) and GI.2 (33.3%), while GII.5 accounted for 11.1%. In conclusion, this study demonstrates the diversity of NoV and SaV, and the emergence of NoV GII.P16/GII.2 recombinant strains in 2016 and 2017 in Chiang Mai, Thailand.


Assuntos
Infecções por Caliciviridae/virologia , Doenças Transmissíveis Emergentes/virologia , Genótipo , Norovirus/genética , Recombinação Genética , Sapovirus/genética , Adolescente , Infecções por Caliciviridae/epidemiologia , Criança , Pré-Escolar , Doenças Transmissíveis Emergentes/epidemiologia , Fezes/virologia , Feminino , Hospitalização , Humanos , Lactente , Masculino , Epidemiologia Molecular , Norovirus/classificação , Norovirus/isolamento & purificação , Estudos Prospectivos , Sapovirus/classificação , Sapovirus/isolamento & purificação , Tailândia/epidemiologia
15.
BMC Infect Dis ; 19(1): 370, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31046684

RESUMO

BACKGROUND: Several inactivated enterovirus-A71 (EV-A71) vaccines are currently licensed in China; however, the development of additional EV-A71 vaccines is ongoing, necessitating extensive analysis of the molecular epidemiology of the virus worldwide. Until 2012, laboratory confirmation of EV-A71 for hand, foot, and mouth disease (HFMD) and other associated diseases had not occurred in the Philippines. Because EV-A71 has been linked with cases of acute flaccid paralysis (AFP), AFP surveillance is one strategy for documenting its possible circulation in the country. To expand current knowledge on EV-A71, molecular epidemiologic analysis and genetic characterization of EV-A71 isolates were performed in this study. METHODS: A retrospective study was performed to identify and characterize nonpolio enteroviruses (NPEVs) associated with AFP in the Philippines, and nine samples were found to be EV-A71-positive. Following characterization of these EV-A71 isolates, the complete viral protein 1 (VP1) gene was targeted for phylogenetic analysis. RESULTS: Nine EV-A71 isolates detected in 2000 (n = 2), 2002 (n = 4), 2005 (n = 2), and 2010 (n = 1) were characterized using molecular methods. Genomic regions spanning the complete VP1 region were amplified and sequenced using specific primers. Phylogenetic analysis of the full-length VP1 region identified all nine EV-A71 Philippine isolates as belonging to the genogroup C lineage, specifically the C2 cluster. The result indicated a genetic linkage with several strains isolated in Japan and Taiwan, suggesting that strains in the C2 cluster identified in the Asia-Pacific region were circulating in the Philippines. CONCLUSION: The study presents the genetic analysis of EV-A71 in the Philippines. Despite some limitations, the study provides additional genetic data on the circulating EV-A71 strains in the Asia-Pacific region, in which information on EV-A71 molecular epidemiology is incomplete. Considering that EV-A71 has a significant public health impact in the region, knowledge of its circulation in each country is important, especially for formulating vaccines covering a wide variety of strains.


Assuntos
Infecções por Enterovirus/diagnóstico , Paralisia/diagnóstico , Doença Aguda , Animais , Proteínas do Capsídeo/genética , Criança , Pré-Escolar , Enterovirus Humano A/classificação , Enterovirus Humano A/genética , Enterovirus Humano A/isolamento & purificação , Infecções por Enterovirus/virologia , Fezes/virologia , Febre Aftosa/diagnóstico , Febre Aftosa/virologia , Genótipo , Humanos , Lactente , Paralisia/virologia , Filipinas , Filogenia , RNA Viral/isolamento & purificação , RNA Viral/metabolismo , Estudos Retrospectivos
16.
J Infect Dis ; 218(7): 1045-1053, 2018 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-29722817

RESUMO

Background: Human respiratory syncytial virus (RSV) is the leading cause of severe acute respiratory infection in infants and young children, which is characterized by repeated infections. However, the role of amino acid substitutions in repeated infections remains unclear. Hence, this study aimed to elucidate the genetic characteristics of RSV in children with repeated infections using molecular analyses of F and G genes. Methods: We conducted a cohort study of children younger than 5 years in the Philippines. We collected nasopharyngeal swabs from children with acute respiratory symptoms and compared F and G sequences between initial and subsequent RSV infections. Results: We examined 1802 children from May 2014 to January 2016 and collected 3471 samples. Repeated infections were observed in 25 children, including 4 with homologous RSV-B reinfections. Viruses from the 4 pairs of homologous reinfections had amino acid substitutions in the G protein mostly at O-glycosylation sites, whereas changes in the F protein were identified at antigenic sites V (L173S) and θ (Q209K), considered essential epitopes for the prefusion conformation of the F protein. Conclusions: Amino acid substitutions in G and F proteins of RSV-B might have led to antigenic changes, potentially contributing to homologous reinfections observed in this study.


Assuntos
Antígenos Virais/imunologia , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sincicial Respiratório Humano/genética , Infecções Respiratórias/virologia , Doença Aguda , Substituição de Aminoácidos , Pré-Escolar , Estudos de Coortes , Epitopos , Feminino , Proteínas de Ligação ao GTP/genética , Humanos , Lactente , Masculino , Filipinas/epidemiologia , Filogenia , Infecções por Vírus Respiratório Sincicial/patologia , Vírus Sincicial Respiratório Humano/imunologia , Vírus Sincicial Respiratório Humano/isolamento & purificação , Infecções Respiratórias/patologia , Proteínas Virais de Fusão/genética
18.
Clin Infect Dis ; 66(12): 1858-1863, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29309577

RESUMO

Background: Sapovirus is one of the primary viral causes of acute gastroenteritis (AGE), especially where rotavirus vaccination has been implemented. The characteristics and impact of natural infection at the community level, however, have not been well documented. Methods: Stool samples were analyzed from 100 children randomly selected from a community-based birth cohort study in Peru. All diarrheal and 1 nondiarrheal stools collected trimonthly from children up to age 2 years (n = 1669) were tested for sapovirus detection. Viral shedding duration was determined by testing additional weekly samples (n = 440) collected before and after a sapovirus-positive sample. Results: The incidence of sapovirus infection in the first and second years of life was 4.3 and 11.1 per 100 child-months, respectively. By age 2 years, 82% of children had at least 1 sapovirus infection, and 64% had at least 1 sapovirus-associated diarrhea episode. The median shedding period was 18.5 days. In 112 of 175 infections, 14 genotypes from 4 genogroups (GI, GII, GIV, and GV) were determined. Among genogroups, GI were more frequently found in symptomatic infections than in asymptomatic infections (odds ratio, 3.1; 95% confidence interval, 1.3-7.4). Fifty-nine children had serial sapovirus infections, but only 3 had repeated infection of the same genotype. Conclusions: Sapovirus was frequently detected in children with AGE at the community level during the first 2 years of life. Serial sapovirus infections by multiple genotypes in a child suggest genotype-specific immunity from each infection, which needs to be taken into account for vaccine development.


Assuntos
Infecções por Caliciviridae/epidemiologia , Diarreia/virologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Sapovirus/isolamento & purificação , Estudos de Coortes , Diarreia/epidemiologia , Fezes/virologia , Feminino , Genótipo , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Peru/epidemiologia , Filogenia , Saúde Pública , Eliminação de Partículas Virais
19.
J Virol ; 90(9): 4383-93, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26889033

RESUMO

UNLABELLED: The Epstein-Barr virus (EBV) is etiologically linked to approximately 10% of gastric cancers, in which viral genomes are maintained as multicopy episomes. EBV-positive gastric cancer cells are incompetent for progeny virus production, making viral DNA cloning extremely difficult. Here we describe a highly efficient strategy for obtaining bacterial artificial chromosome (BAC) clones of EBV episomes by utilizing a CRISPR/Cas9-mediated strand break of the viral genome and subsequent homology-directed repair. EBV strains maintained in two gastric cancer cell lines (SNU719 and YCCEL1) were cloned, and their complete viral genome sequences were determined. Infectious viruses of gastric cancer cell-derived EBVs were reconstituted, and the viruses established stable latent infections in immortalized keratinocytes. While Ras oncoprotein overexpression caused massive vacuolar degeneration and cell death in control keratinocytes, EBV-infected keratinocytes survived in the presence of Ras expression. These results implicate EBV infection in predisposing epithelial cells to malignant transformation by inducing resistance to oncogene-induced cell death. IMPORTANCE: Recent progress in DNA-sequencing technology has accelerated EBV whole-genome sequencing, and the repertoire of sequenced EBV genomes is increasing progressively. Accordingly, the presence of EBV variant strains that may be relevant to EBV-associated diseases has begun to attract interest. Clearly, the determination of additional disease-associated viral genome sequences will facilitate the identification of any disease-specific EBV variants. We found that CRISPR/Cas9-mediated cleavage of EBV episomal DNA enabled the cloning of disease-associated viral strains with unprecedented efficiency. As a proof of concept, two gastric cancer cell-derived EBV strains were cloned, and the infection of epithelial cells with reconstituted viruses provided important clues about the mechanism of EBV-mediated epithelial carcinogenesis. This experimental system should contribute to establishing the relationship between viral genome variation and EBV-associated diseases.


Assuntos
Sistemas CRISPR-Cas/genética , Clonagem Molecular , DNA Viral , Genoma Viral , Herpesvirus Humano 4/genética , Sequência de Bases , Linhagem Celular Tumoral , Cromossomos Artificiais Bacterianos , Biologia Computacional/métodos , Efeito Citopatogênico Viral , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/virologia , Marcação de Genes/métodos , Humanos , Anotação de Sequência Molecular , Dados de Sequência Molecular , Filogenia , Plasmídeos/genética , Alinhamento de Sequência , Análise de Sequência de DNA , Neoplasias Gástricas/etiologia , Proteínas Virais/química , Proteínas Virais/genética , Proteínas Virais/metabolismo , Replicação Viral , Proteínas ras/genética , Proteínas ras/metabolismo
20.
J Virol ; 90(18): 8251-65, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27384661

RESUMO

Since influenza C virus was first isolated in 1947, the virus has been only occasionally isolated by cell culture; there are only four strains for which complete genome sequences are registered. Here, we analyzed a total of 106 complete genomes, ranging from the first isolate from 1947 to recent isolates from 2014, to determine the genetic lineages of influenza C virus, the reassortment events, and the rates of nucleotide substitution. The results showed that there are six lineages, named C/Taylor, C/Mississippi, C/Aichi, C/Yamagata, C/Kanagawa, and C/Sao Paulo. They contain both antigenic and genetic lineages of the hemagglutinin-esterase (HE) gene, and the internal genes PB2, PB1, P3, NP, M, and NS are divided into two major lineages, a C/Mississippi/80-related lineage and a C/Yamagata/81-related lineage. Reassortment events were found over the entire period of 68 years. Several outbreaks of influenza C virus between 1990 and 2014 in Japan consisted of reassortant viruses, suggesting that the genomic constellation is related to influenza C virus epidemics. The nucleotide sequences were highly homologous to each other. The minimum percent identity between viruses ranged from 91.1% for the HE gene to 96.1% for the M gene, and the rate of nucleotide substitution for the HE gene was the highest, at 5.20 × 10(-4) substitutions/site/year. These results indicate that reassortment is an important factor that increases the genetic diversity of influenza C virus, resulting in its ability to prevail in humans. IMPORTANCE Influenza C virus is a pathogen that causes acute respiratory illness in children and results in hospitalization of infants. We previously demonstrated (Y. Matsuzaki et al., J Clin Virol 61:87-93, 2014, http://dx.doi.org/10.1016/j.jcv.2014.06.017) that periodic epidemics of this virus occurred in Japan between 1996 and 2014 and that replacement of the dominant antigenic group occurred every several years as a result of selection by herd immunity. However, the antigenicity of the HE glycoprotein is highly stable, and antigenic drift has not occurred for at least 30 years. Here, we analyzed a total of 106 complete genomes spanning 68 years for the first time, and we found that influenza C viruses are circulating worldwide while undergoing reassortment as well as selection by herd immunity, resulting in an increased ability to prevail in humans. The results presented in this study contribute to the understanding of the evolution, including reassortment events, underlying influenza C virus epidemics.


Assuntos
Evolução Molecular , Gammainfluenzavirus/classificação , Gammainfluenzavirus/genética , Variação Genética , Influenza Humana/virologia , Vírus Reordenados/classificação , Vírus Reordenados/genética , Biologia Computacional , Surtos de Doenças , Genótipo , Saúde Global , Humanos , Influenza Humana/epidemiologia , Gammainfluenzavirus/isolamento & purificação , Vírus Reordenados/isolamento & purificação , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico
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