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1.
J Infect Dis ; 212(10): 1592-9, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25948864

RESUMO

BACKGROUND: In 2012, one third of cases in a multistate outbreak of variant influenza A(H3N2) virus ([H3N2]v) infection occurred in Ohio. We conducted an investigation of (H3N2)v cases associated with agricultural Fair A in Ohio. METHODS: We surveyed Fair A swine exhibitors and their household members. Confirmed cases had influenza-like illness (ILI) and a positive laboratory test for (H3N2)v, and probable cases had ILI. We calculated attack rates. We determined risk factors for infection, using multivariable log-binomial regression. RESULTS: We identified 20 confirmed and 94 probable cases associated with Fair A. Among 114 cases, the median age was 10 years, there were no hospitalizations or deaths, and 82% had swine exposure. In the exhibitor household cohort of 359 persons (83 households), we identified 6 confirmed cases (2%) and 40 probable cases (11%). An age of <10 years was a significant risk factor (P < .01) for illness. One instance of likely human-to-human transmission was identified. CONCLUSIONS: In this (H3N2)v outbreak, no evidence of sustained human-to-human (H3N2)v transmission was found. Our risk factor analysis contributed to the development of the recommendation that people at increased risk of influenza-associated complications, including children aged <5 years, avoid swine barns at fairs during the 2012 fair season.


Assuntos
Aglomeração , Surtos de Doenças , Vírus da Influenza A Subtipo H3N2/classificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Influenza Humana/epidemiologia , Influenza Humana/virologia , Exposição Ocupacional , Adolescente , Adulto , Fatores Etários , Idoso , Animais , Criança , Pré-Escolar , Estudos de Coortes , Transmissão de Doença Infecciosa , Feminino , Humanos , Lactente , Vírus da Influenza A Subtipo H3N2/genética , Masculino , Pessoa de Meia-Idade , Ohio/epidemiologia , Fatores de Risco , Suínos , Adulto Jovem
2.
Emerg Infect Dis ; 21(2): 202-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25625302

RESUMO

Co-circulation of influenza A(H5N1) and seasonal influenza viruses among humans and animals could lead to co-infections, reassortment, and emergence of novel viruses with pandemic potential. We assessed the timing of subtype H5N1 outbreaks among poultry, human H5N1 cases, and human seasonal influenza in 8 countries that reported 97% of all human H5N1 cases and 90% of all poultry H5N1 outbreaks. In these countries, most outbreaks among poultry (7,001/11,331, 62%) and half of human cases (313/625, 50%) occurred during January-March. Human H5N1 cases occurred in 167 (45%) of 372 months during which outbreaks among poultry occurred, compared with 59 (10%) of 574 months that had no outbreaks among poultry. Human H5N1 cases also occurred in 59 (22%) of 267 months during seasonal influenza periods. To reduce risk for co-infection, surveillance and control of H5N1 should be enhanced during January-March, when H5N1 outbreaks typically occur and overlap with seasonal influenza virus circulation.


Assuntos
Saúde Global , Virus da Influenza A Subtipo H5N1 , Influenza Aviária/epidemiologia , Influenza Humana/epidemiologia , Aves Domésticas , Estações do Ano , Animais , Surtos de Doenças , Geografia Médica , História do Século XXI , Humanos , Influenza Aviária/história , Influenza Aviária/virologia , Influenza Humana/história , Influenza Humana/virologia , Fatores de Tempo
3.
BMC Infect Dis ; 15: 447, 2015 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-26497393

RESUMO

BACKGROUND: Although information about the incidence of viral respiratory illnesses and their associated cost can help health officials explore the value of interventions, data are limited from middle-income countries. METHODS: During 2008-2010, we conducted a prospective cohort study and followed ~1,800 Argentinian children aged ≤5 years to identify those children who were hospitalized or who sought care at an emergency room with any acute respiratory infection sign or symptom (e.g., rhinorrhea, cough, wheezing, tachypnea, retractions, or cyanosis). Respiratory samples were obtained for respiratory syncytial virus, influenza, parainfluenza, adenovirus, and metapneumovirus testing by immunofluorescence and for rhinovirus by real-time reverse transcription polymerase chain reaction. RESULTS: The incidence of respiratory syncytial virus (24/1000 children-years), human metapneumovirus (8/1000 children-years), and influenza (8/1000 children-years) illnesses was highest among hospitalized children aged <6 months and decreased among older children. In contrast, the incidence of rhinovirus was highest (12/1000 children-years) among those aged 6-23 months. In the emergency room, the incidence of rhinovirus was 459; respiratory syncytial virus 352; influenza 185; parainfluenza 177; metapneumovirus 130; and adenovirus 73/1,000 children-years. The total cost of hospitalization was a median of US$529 (Interquartile range, US$362-789). CONCLUSIONS: Our findings indicate that respiratory viruses, in particular rhinovirus, respiratory syncytial virus, metapneumovirus, and influenza may be associated with severe illness causing substantial economic burden.


Assuntos
Infecções Respiratórias/diagnóstico , Viroses/diagnóstico , Argentina/epidemiologia , Criança Hospitalizada , Pré-Escolar , Estudos de Coortes , Demografia , Serviço Hospitalar de Emergência/economia , Feminino , Humanos , Incidência , Lactente , Masculino , Metapneumovirus/genética , Metapneumovirus/isolamento & purificação , Microscopia de Fluorescência , Orthomyxoviridae/genética , Orthomyxoviridae/isolamento & purificação , Pacientes Ambulatoriais , Infecções por Paramyxoviridae/epidemiologia , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , Vírus Sinciciais Respiratórios/genética , Vírus Sinciciais Respiratórios/isolamento & purificação , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Rhinovirus/genética , Rhinovirus/isolamento & purificação , Viroses/economia , Viroses/epidemiologia
4.
Clin Infect Dis ; 57(12): 1703-12, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24065322

RESUMO

BACKGROUND: Variant influenza virus infections are rare but may have pandemic potential if person-to-person transmission is efficient. We describe the epidemiology of a multistate outbreak of an influenza A(H3N2) variant virus (H3N2v) first identified in 2011. METHODS: We identified laboratory-confirmed cases of H3N2v and used a standard case report form to characterize illness and exposures. We considered illness to result from person-to-person H3N2v transmission if swine contact was not identified within 4 days prior to illness onset. RESULTS: From 9 July to 7 September 2012, we identified 306 cases of H3N2v in 10 states. The median age of all patients was 7 years. Commonly reported signs and symptoms included fever (98%), cough (85%), and fatigue (83%). Sixteen patients (5.2%) were hospitalized, and 1 fatal case was identified. The majority of those infected reported agricultural fair attendance (93%) and/or contact with swine (95%) prior to illness. We identified 15 cases of possible person-to-person transmission of H3N2v. Viruses recovered from patients were 93%-100% identical and similar to viruses recovered from previous cases of H3N2v. All H3N2v viruses examined were susceptible to oseltamivir and zanamivir and resistant to adamantane antiviral medications. CONCLUSIONS: In a large outbreak of variant influenza, the majority of infected persons reported exposures, suggesting that swine contact at an agricultural fair was a risk for H3N2v infection. We identified limited person-to-person H3N2v virus transmission, but found no evidence of efficient or sustained person-to-person transmission. Fair managers and attendees should be aware of the risk of swine-to-human transmission of influenza viruses in these settings.


Assuntos
Surtos de Doenças , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Influenza Humana/epidemiologia , Influenza Humana/virologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Busca de Comunicante , Feminino , Hospitalização , Humanos , Lactente , Influenza Humana/transmissão , Masculino , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Adulto Jovem
5.
J Virol ; 82(21): 10591-9, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18753202

RESUMO

ICP22 is a multifunctional herpes simplex virus 1 (HSV-1) regulatory protein that regulates the accumulation of a subset of late (gamma(2)) proteins exemplified by U(L)38, U(L)41, and U(S)11. ICP22 binds the cyclin-dependent kinase 9 (cdk9) but not cdk7, and this complex in conjunction with viral protein kinases phosphorylates the carboxyl terminus of RNA polymerase II (Pol II) in vitro. The primary function of cdk9 and its partners, the cyclin T variants, is in the elongation of RNA transcripts, although functions related to the initiation and processing of transcripts have also been reported. We report two series of experiments designed to probe the role of cdk9 in infected cells. In the first, infected cells were treated with 5,6-dichloro-1-beta-d-ribofuranosylbenzimidazole (DRB), a specific inhibitor of cdk9. In cells treated with DRB, the major effect was in the accumulation of viral RNAs and proteins regulated by ICP22. The accumulation of alpha, beta, or gamma proteins not regulated by ICP22 was not affected by the drug. The results obtained with DRB were duplicated in cells transfected with small interfering RNA (siRNA) targeting cdk9 mRNAs. Interestingly, DRB and siRNA reduced the levels of ICP22 but not those of other alpha gene products. In addition, cdk9 and ICP22 appeared to colocalize with RNA Pol II in wild-type-virus-infected cells but not in DeltaU(L)13-infected cells. We conclude that cdk9 plays a critical role in the optimization of expression of genes regulated by ICP22 and that one function of cdk9 in HSV-1-infected cells may be to bring ICP22 into the RNA Pol II transcriptional complex.


Assuntos
Quinase 9 Dependente de Ciclina/metabolismo , Regulação Viral da Expressão Gênica , Herpesvirus Humano 1/fisiologia , Proteínas Imediatamente Precoces/metabolismo , Proteínas Virais/biossíntese , Linhagem Celular , Quinase 9 Dependente de Ciclina/antagonistas & inibidores , Diclororribofuranosilbenzimidazol/farmacologia , Inibidores Enzimáticos/farmacologia , Humanos , Ligação Proteica , RNA Polimerase II/metabolismo
6.
J Virol ; 82(9): 4527-32, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18272575

RESUMO

Earlier studies have shown that in herpes simplex virus 1-infected cells, ICP22 upregulates the accumulation of a subset of gamma(2) proteins exemplified by the products of the U(L)38, U(L)41, and U(S)11 genes. The ICP22-dependent process involves degradation of cyclins A and B1, the stabilization and activation of cdc2, physical interaction of activated cdc2 with the U(L)42 DNA synthesis processivity factor, and recruitment and phosphorylation of topoisomerase IIalpha by the cdc2/U(L)42 complex. Activation of cdc2, the first step in the process, is a key function of the mitotic phosphatase cdc25C. To define the role of cdc25C, we probed some features of the ICP22-dependent pathway of upregulation of gamma(2) genes in cdc25C(-/-) cells and in cdc25C(+/+) cells derived from sibling mice. We report that cyclin B1 turned over in cdc25C(+/+) or cdc25C(-/-) cells at the same rate, that cdc2 increased in amount, and that U(S)11 and U(L)38 proteins and infectious virus accumulated in smaller amounts than in wild-type infected cells. The reduction in U(L)38 protein accumulation and virus was greater in cdc25C(-/-) cells infected with virus lacking ICP22 than in cells infected with wild-type virus. We conclude that cdc25C phosphatase plays a role in viral replication and that this role extends beyond its function of activating cdc2 for initiation of the ICP22-dependent cascade for upregulation of gamma(2) gene expression.


Assuntos
Proteína Quinase CDC2/metabolismo , Regulação Viral da Expressão Gênica , Herpesvirus Humano 1/fisiologia , Proteínas Imediatamente Precoces/fisiologia , Proteínas Virais Reguladoras e Acessórias/fisiologia , Replicação Viral/genética , Fosfatases cdc25/fisiologia , Animais , Proteínas do Capsídeo , Linhagem Celular , Células Cultivadas , Humanos , Camundongos , Proteínas de Ligação a RNA , Regulação para Cima , Proteínas Virais/genética
7.
PLoS One ; 14(2): e0212445, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30794619

RESUMO

Many countries, including South Africa, have implemented population-based household surveys to estimate HIV prevalence and the burden of HIV infection. Most household HIV surveys are designed to provide reliable estimates down to only the first subnational geopolitical level which, in South Africa, is composed of nine provinces. However HIV prevalence estimates are needed down to at least the second subnational level in order to better target the delivery of HIV care, treatment and prevention services. The second subnational level in South Africa is composed of 52 districts. Achieving adequate precision at the second subnational level therefore requires either a substantial increase in survey sample size or use of model-based estimation capable of incorporating other pre-existing data. Our purpose is demonstration of the efficacy of relatively simple small-area estimation of HIV prevalence in the 52 districts of South Africa using data from the South African National HIV Prevalence, Incidence and Behavior Survey, 2012, district-level HIV prevalence estimates obtained from testing of pregnant women who attended antenatal care (ANC) clinics in 2012, and 2012 demographic data. The best-fitting model included only ANC prevalence and dependency ratio as out-of-survey predictors. Our key finding is that ANC prevalence was the superior auxiliary covariate, and provided substantially improved precision in many district-level estimates of HIV prevalence in the general population. Inclusion of a district-level spatial simultaneously autoregressive covariance structure did not result in improved estimation.


Assuntos
Infecções por HIV/epidemiologia , Efeitos Psicossociais da Doença , Monitoramento Epidemiológico , Feminino , Geografia , Infecções por HIV/complicações , Infecções por HIV/prevenção & controle , Inquéritos Epidemiológicos , Humanos , Masculino , Modelos Estatísticos , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Cuidado Pré-Natal , Prevalência , Vigilância de Evento Sentinela , África do Sul/epidemiologia
8.
Ghana Med J ; 53(1): 59-62, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31138945

RESUMO

BACKGROUND: The aim of this review was to summarize the data on HIV/AIDS epidemiology and affected populations in Ghana and to describe the United States President's Emergency Plan for Emergency Relief's (PEPFAR) response to the epidemic. DESIGN: We conducted a literature review focusing on PEPFAR's contribution to the HIV response in Ghana. Additionally, we summarized the epidemiology of HIV. We searched both peer-reviewed and grey literature. SETTING: Ghana. RESULTS: Overall, HIV prevalence in Ghana is 1.6% with regional variation. Key populations (KPs) are disproportionately affected by HIV in the country. FSW and their clients, and MSM, account for 28% of all new infections. PEPFAR provides technical assistance (TA) to Ghana to maximize the quality, coverage and impact of the national HIV/AIDS response. To ensure adequate supply of antiretrovirals (ARVs), in 2016-2017, PEPFAR invested $23.7 million as a onetime supplemental funding to support Ghana's ARV treatment program. In addition, the National AIDS Control Programme in collaboration with PEPFAR is implementing a scale up of viral load testing. PEPFAR is also implementing a comprehensive package of prevention services in five regions to help reach MSM and FSW and to expand HIV testing services for KPs. CONCLUSIONS: Ghana is making changes at both policy and program level in the fight against HIV/AIDS and is working towards achieving the UNAIDS' 90-90-90 targets. PEPFAR is providing TA to ensure these goals can be achieved. FUNDING: This manuscript has been supported by the U.S. President's Emergency Plan for AIDS Relief (PEPFAR) through the Centers for Disease Control and Prevention (CDC).


Assuntos
Fármacos Anti-HIV/economia , Fármacos Anti-HIV/provisão & distribuição , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Cooperação Internacional , Fármacos Anti-HIV/uso terapêutico , Países em Desenvolvimento , Gana/epidemiologia , Homossexualidade , Humanos , Prevalência , Avaliação de Programas e Projetos de Saúde , Carga Viral
9.
Influenza Other Respir Viruses ; 10(3): 170-5, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26701079

RESUMO

BACKGROUND: Influenza-associated illness results in increased morbidity and mortality in the Americas. These effects can be mitigated with an appropriately chosen and timed influenza vaccination campaign. To provide guidance in choosing the most suitable vaccine formulation and timing of administration, it is necessary to understand the timing of influenza seasonal epidemics. OBJECTIVES: Our main objective was to determine whether influenza occurs in seasonal patterns in the American tropics and when these patterns occurred. METHODS: Publicly available, monthly seasonal influenza data from the Pan American Health Organization and WHO, from countries in the American tropics, were obtained during 2002-2008 and 2011-2014 (excluding unseasonal pandemic activity during 2009-2010). For each country, we calculated the monthly proportion of samples that tested positive for influenza. We applied the monthly proportion data to a logistic regression model for each country. RESULTS: We analyzed 2002-2008 and 2011-2014 influenza surveillance data from the American tropics and identified 13 (81%) of 16 countries with influenza epidemics that, on average, started during May and lasted 4 months. CONCLUSIONS: The majority of countries in the American tropics have seasonal epidemics that start in May. Officials in these countries should consider the impact of vaccinating persons during April with the Southern Hemisphere formulation.


Assuntos
Vacinas contra Influenza , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Pandemias/estatística & dados numéricos , Clima Tropical , Brasil/epidemiologia , Monitoramento Epidemiológico , Humanos , Vacinas contra Influenza/química , Influenza Humana/virologia , Nicarágua/epidemiologia , Pandemias/prevenção & controle , Peru/epidemiologia , Vigilância da População , Estações do Ano , Fatores de Tempo , Estados Unidos/epidemiologia , Vacinação
10.
J Virol ; 79(11): 6757-62, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15890914

RESUMO

The infected-cell protein 22 (ICP22), a regulatory protein encoded by the alpha22 gene of herpes simplex virus 1, is required for the optimal expression of a set of late viral proteins that includes the products of the U(S)11, U(L)38, and U(L)41 genes. ICP22 has two activities. Thus, ICP22 and the U(L)13 protein kinase mediate the activation of cdc2 and degradation of its partners, cyclins A and B. cdc2 and its new partner, the DNA polymerase accessory factor (U(L)42), bind topoisomerase IIalpha in an ICP22-dependent manner. In addition, ICP22 and U(L)13 mediate an intermediate phosphorylation of the carboxyl terminus of RNA polymerase II (RNA POL II). Here we report another function of ICP22. Thus, ICP22 physically interacts with cdk9, a constitutively active cyclin-dependent kinase involved in transcriptional regulation. A protein complex containing ICP22 and cdk9 phosphorylates in vitro the carboxyl-terminal domain of RNA POL II in a viral U(S)3 protein kinase-dependent fashion. Finally, the carboxyl-terminal domain of RNA POL II fused to glutathione S-transferase is phosphorylated in reaction mixtures containing complexes pulled down with ICP22 or cdk9 immune precipitated from lysates of wild-type parent virus or deltaU(L)13 but not deltaU(S)3 mutant-infected cells. The experiments described here place ICP22 and cdk9 in a complex with the carboxyl-terminal domain of RNA POL II. At the same time we confirm the requirement of ICP22 and the U(L)13 protein kinase in the posttranslational modification of RNA POL II that alters its electrophoretic mobility, although U(S)3 kinase appears to play a role in a cell-type-dependent fashion.


Assuntos
Quinase 9 Dependente de Ciclina/metabolismo , Herpesvirus Humano 1/fisiologia , Proteínas Imediatamente Precoces/metabolismo , RNA Polimerase II/química , RNA Polimerase II/metabolismo , Linhagem Celular , Ciclina T , Quinase 9 Dependente de Ciclina/química , Ciclinas/metabolismo , Genes Virais , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/patogenicidade , Humanos , Proteínas Imediatamente Precoces/química , Proteínas Imediatamente Precoces/genética , Peso Molecular , Complexos Multiproteicos , Mutação , Fosforilação , Proteínas Quinases/química , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Processamento de Proteína Pós-Traducional , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Virais Reguladoras e Acessórias , Replicação Viral
11.
J Virol ; 77(22): 11927-32, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14581529

RESUMO

In herpes simplex virus 1-infected cells, a high level of alpha gene expression requires the transactivation of the genes by a complex containing the viral alpha transinducing factor (alphaTIF) and two cellular proteins. The latter two, HCF-1 and octamer binding protein Oct-1, are transcriptional factors regulated in a cell cycle-dependent manner. alphaTIF is a protein made late in infection but packaged with the virion to transactivate viral genes in newly infected cells. In light of the accumulation of large amounts of alphaTIF, the absence of alpha gene expression late in infection suggested the possibility that one or more transcriptional factors required for alpha gene expression is modified late in infection. Here we report that Oct-1 is posttranscriptionally modified late in infection, that the modification is mediated by the virus but does not involve viral protein kinases or cdc2 kinase activated by the virus late in infection, and that the modified Oct-1 has a reduced affinity for its cognate DNA site. These results are consistent with the hypothesis that modification of Oct-1 transcriptional factor could account at least in part for the shutoff of alpha gene expression late in infection.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Herpesvirus Humano 1/genética , Processamento de Proteína Pós-Traducional , Fatores de Transcrição/metabolismo , Sítios de Ligação , DNA/metabolismo , Regulação Viral da Expressão Gênica , Células HeLa , Fator C1 de Célula Hospedeira , Humanos , Proteínas Imediatamente Precoces/fisiologia , Nocodazol/farmacologia , Fator 1 de Transcrição de Octâmero , Proteínas Quinases/fisiologia , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Virais
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