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1.
Microbiol Spectr ; 12(1): e0297923, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38047694

RESUMO

IMPORTANCE: We present a protocol to efficiently sequence genomes of the MPXV-causing mpox. This enables researchers and public health agencies to acquire high-quality genomic data using a rapid and cost-effective approach. Genomic data can be used to conduct surveillance and investigate mpox outbreaks. We present 91 mpox genomes that show the diversity of the 2022 mpox outbreak in Ontario, Canada.


Assuntos
Monkeypox virus , Mpox , Humanos , Monkeypox virus/genética , Sequenciamento Completo do Genoma , Genômica , Surtos de Doenças , Ontário/epidemiologia
2.
Sci Rep ; 9(1): 12615, 2019 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-31471545

RESUMO

In 2017 Ontario experienced the largest mumps outbreak in the province in 8 years, at a time when multiple outbreaks were occurring across North America. Of 259 reported cases, 143 occurred in Toronto, primarily among young adults. Routine genotyping of the small hydrophobic gene indicated that the outbreak was due to mumps virus genotype G. We performed a retrospective study of whole genome sequencing of 26 mumps virus isolates from early in the outbreak, using a tiling amplicon method. Results indicated that two of the cases were genetically divergent, with the remaining 24 cases belonging to two major clades and one minor clade. Phylogeographic analysis confirmed circulation of virus from each clade between Toronto and other regions in Ontario. Comparison with other genotype G strains from North America suggested that the presence of co-circulating major clades may have been due to separate importation events from outbreaks in the United States. A transmission network analysis performed with the software program TransPhylo was compared with previously collected epidemiological data. The transmission tree correlated with known epidemiological links between nine patients and identified new potential clusters with no known epidemiological links.


Assuntos
Genoma Viral/genética , Vírus da Caxumba/genética , Caxumba/genética , Filogenia , Surtos de Doenças , Genótipo , Humanos , Caxumba/epidemiologia , Caxumba/virologia , Vírus da Caxumba/patogenicidade , Ontário/epidemiologia , RNA Viral/genética , Estados Unidos/epidemiologia , Sequenciamento Completo do Genoma
3.
Curr Infect Dis Rep ; 20(10): 37, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30069735

RESUMO

PURPOSE OF REVIEW: Zoonotic influenza viruses are those that cross the animal-human barrier and can cause disease in humans, manifesting from minor respiratory illnesses to multiorgan dysfunction. They have also been implicated in the causation of deadly pandemics in recent history. The increasing incidence of infections caused by these viruses worldwide has necessitated focused attention to improve both diagnostic as well as treatment modalities. In this first part of a two-part review, we describe the structure of zoonotic influenza viruses, the relationship between mutation and pandemic capacity, pathogenesis of infection, and also discuss history and epidemiology. RECENT FINDINGS: We are currently witnessing the fifth and the largest wave of the avian influenza A(H7N9) epidemic. Also in circulation are a number of other zoonotic influenza viruses, including avian influenza A(H5N1) and A(H5N6); avian influenza A(H7N2); and swine influenza A(H1N1)v, A(H1N2)v, and A(H3N2)v viruses. Most recently, the first human case of avian influenza A(H7N4) infection has been documented. By understanding the virology and epidemiology of emerging zoonotic influenzas, we are better prepared to face a new pandemic. However, continued effort is warranted to build on this knowledge in order to efficiently combat the constant threat posed by the zoonotic influenza viruses.

4.
Curr Infect Dis Rep ; 20(10): 38, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30069787

RESUMO

PURPOSE OF REVIEW: Zoonotic influenza viruses are those influenza viruses that cross the animal-human barrier and can cause disease in humans, manifesting from minor respiratory illnesses to multiorgan dysfunction. The increasing incidence of infections caused by these viruses worldwide has necessitated focused attention to improve both diagnostic as well as treatment modalities. In this second part of a two-part review, we discuss the clinical features, diagnostic modalities, and treatment of zoonotic influenza, and provide an overview of prevention strategies. RECENT FINDINGS: Illnesses caused by novel reassortant avian influenza viruses continue to be detected and described; most recently, a human case of avian influenza A(H7N4) has been described from China. We continue to witness increasing rates of A(H7N9) infections, with the latest (fifth) wave, from late 2016 to 2017, being the largest to date. The case fatality rate for A(H7N9) and A(H5N1) infections among humans is much higher than that of seasonal influenza infections. Since the emergence of the A(H1N1) 2009 pandemic, and subsequently A(H7N9), testing and surveillance for novel influenzas have become more effective. Various newer treatment options, including peramivir, favipiravir (T-705), and DAS181, and human or murine monoclonal antibodies have been evaluated in vitro and in animal models. Armed with robust diagnostic modalities, antiviral medications, vaccines, and advanced surveillance systems, we are today better prepared to face a new influenza pandemic and to limit the burden of zoonotic influenza than ever before. Sustained efforts and robust research are necessary to efficiently deal with the highly mutagenic zoonotic influenza viruses.

5.
Euro Surveill ; 20(16)2015 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-25953275

RESUMO

Prompt evaluation of annual influenza vaccine effectiveness (IVE) is important. IVE is estimated in Ontario using a test-negative design (TND) within a national sentinel surveillance network (SPSN). To explore alternative approaches, we applied the screening method (SM) during five seasons spanning 2007 to 2012 to passive surveillance data to determine whether routinely collected data could provide unbiased IVE estimates. Age-adjusted SM-IVE estimates, excluding 2008/09 pandemic cases and cases with missing immunisation status, were compared with TND-IVE estimates in SPSN participants, adjusted for age, comorbidity, week of illness onset and interval to specimen collection. In four seasons, including the 2009 pandemic, the SM underestimated IVE (22­39% seasonal; 72% pandemic) by 20 to 35% relative to the TND-IVE (58­63% seasonal; 93% pandemic), except for the 2010/11 season when both estimates were low (33% and 30%, respectively). Half of the cases in the routine surveillance data lacked immunisation information; imputing all to be unimmunised better aligned SM-IVE with TND-IVE, instead overestimating in four seasons by 4 to 29%. While the SM approach applied to routine data may offer the advantage of timeliness, ease and efficiency, methodological issues related to completeness of vaccine information and/or case ascertainment may constitute trade-offs in reliability.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/uso terapêutico , Influenza Humana/prevenção & controle , Pandemias/prevenção & controle , Vigilância da População/métodos , Adolescente , Adulto , Idoso , Canadá/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vacinas contra Influenza/imunologia , Influenza Humana/epidemiologia , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Estações do Ano , Adulto Jovem
7.
J Clin Virol ; 57(3): 279-81, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23711507

RESUMO

There has been an increase in influenza A variant detections in the US in recent years. In September 2012, an Ontario resident was diagnosed with influenza A (H1N1) variant infection. The demonstrated cross reactivity with the A(H1N1)pdm09 H1 gene CDC realtime PCR suggests that laboratories that only use the pdm09 H1 gene PCR to confirm this subtype would incorrectly report this variant as a A(H1N1)pdm09 subtype unless they were doing further molecular investigations.


Assuntos
Variação Genética , Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/virologia , Reação em Cadeia da Polimerase/métodos , Adulto , Erros de Diagnóstico , Humanos , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/diagnóstico , Masculino , Ontário
8.
Euro Surveill ; 18(5)2013 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-23399422

RESUMO

The 2012/13 influenza season in Canada has been characterised to date by early and moderately severe activity, dominated (90%) by the A(H3N2) subtype. Vaccine effectiveness (VE) was assessed in January 2013 by Canada's sentinel surveillance network using a test-negative case-control design. Interim adjusted-VE against medically attended laboratory-confirmed influenza A(H3N2) infection was 45% (95% CI: 13-66). Influenza A(H3N2) viruses in Canada are similar to the vaccine, based on haemagglutination inhibition; however, antigenic site mutations are described in the haemagglutinin gene.


Assuntos
Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vacinas contra Influenza/administração & dosagem , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Vigilância de Evento Sentinela , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos Virais/análise , Canadá/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N2/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/diagnóstico , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Nariz/virologia , Médicos de Família , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Resultado do Tratamento
9.
Epidemiol Infect ; 141(8): 1781-5, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23146341

RESUMO

The objective of this study was to determine the optimal number of respiratory samples per outbreak to be tested for institutional respiratory outbreaks in Ontario. We reviewed respiratory samples tested for respiratory viruses by multiplex PCR as part of outbreak investigations. We documented outbreaks that were positive for any respiratory viruses and for influenza alone. At least one virus was detected in 1454 (85∙2%) outbreaks. The ability to detect influenza or any respiratory virus increased as the number of samples tested increased. When analysed by chronological order of when samples were received at the laboratory, percent positivity of outbreaks testing positive for any respiratory virus including influenza increased with the number of samples tested up to the ninth sample, with minimal benefit beyond the fourth sample tested. Testing up to four respiratory samples per outbreak was sufficient to detect viral organisms and resulted in significant savings for outbreak investigations.


Assuntos
Surtos de Doenças/estatística & dados numéricos , Reação em Cadeia da Polimerase Multiplex/métodos , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Idoso , Idoso de 80 Anos ou mais , Criança , Humanos , Recém-Nascido , Influenza Humana/epidemiologia , Influenza Humana/virologia , Reação em Cadeia da Polimerase Multiplex/economia , Ontário/epidemiologia , Estudos de Amostragem
10.
Transpl Infect Dis ; 14(6): 575-83, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22999005

RESUMO

BACKGROUND: Seasonal and pandemic influenza virus infections in renal transplant patients are associated with poor outcomes. During the pandemic of 2009-2010, the AS03-adjuvanted monovalent H1N1 influenza vaccine was recommended for transplant recipients, although its immunogenicity in this population was unknown. We sought to determine the safety and immunogenicity of an adjuvant-containing vaccine against pandemic influenza A H1N1 2009 (pH1N1) administered to kidney transplant recipients. METHODS: We prospectively enrolled 124 adult kidney transplant recipients in the fall of 2009 at two transplant centers. Cohort 1 (n = 42) was assessed before and after pH1N1 immunization, while Cohort 2 (n = 82) was only assessed post immunization. Humoral response was measured by the hemagglutination inhibition assay. Vaccine safety was assessed by adverse event reporting, graft function, and human leukocyte antigen (HLA) alloantibody measurements. RESULTS: Cohort 1 had a low rate of baseline seroprotection to pH1N1 (7%) and a low rate of seroprotection after immunization (31%). No patient <6 months post transplant (n = 5) achieved seroprotection. Seroprotection rate was greater in patients receiving double as compared with triple immunosuppression (80% vs. 24%, P = 0.01). In Cohort 2, post-immunization seroprotection was 35%. In both cohorts, no confirmed cases of pH1N1 infection occurred. No difference was seen in estimated glomerular filtration rate before (54.3 mL/min/1.73 m(2) ) and after (53.8 mL/min/1.73 m(2) ) immunization, and no acute rejections had occurred after immunization at last follow-up. In Cohort 1, 11.9% of patients developed new anti-HLA antibodies. CONCLUSION: An adjuvant-containing vaccine to pH1N1 provided poor seroprotection in renal transplant recipients. Receiving triple immunosuppression was associated with a poor seroresponse. Vaccination appeared safe, but some patients developed new anti-HLA antibodies post vaccination. Alternative strategies to improve vaccine responses are necessary.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Transplante de Rim/imunologia , Pandemias , Adulto , Idoso , Anticorpos Antivirais/sangue , Colúmbia Britânica , Feminino , Humanos , Imunização , Influenza Humana/epidemiologia , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Ontário/epidemiologia
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