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Economic effects of avian influenza on egg producers in Turkey

Demircan,V; Yilmaz,H; Dernek,Z; Bal,T; Gül,M; Koknaroglu,H
Fonte: Fundação APINCO de Ciência e Tecnologia Avícolas Publicador: Fundação APINCO de Ciência e Tecnologia Avícolas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2009 EN
Relevância na Pesquisa
46.09%
This study determined the economic effects of avian influenza on the egg-production sector of Afyon Province, Turkey. Economic indicators were compared before and during the avian influenza outbreak. A questionnaire was conducted with 75 poultry farmers. Farms were divided into three groups according to their size. The profitability of the three farm size groups was compared during two study periods: before and during the avian influenza outbreak. The results indicate that, as compared to previous levels, farms experienced significantly reduced incomes during the avian influenza episode. While net income and profit margin were found to be negative in all three farm groups during the avian influenza period, only group I showed economic loss prior to avian influenza. Average net income per group was -19,576.14, -39,810.11, and -112,035.33 YTL respectively during the avian influenza outbreak, compared with prior incomes of -5,665.51, 8,422.92, and 16,3873.71 YTL (1 USD=1.43 YTL). The profit margin per egg during avian influenza was -0.029, -0.016, -0.010 YTL in group I, II, III, respectively, as compared to -0.007, 0.003, and 0.014 YTL/egg before avian influenza. It was found that, whereas larger farms were more profitable than small farms prior to the avian influenza period...

Haemagglutinin-inhibiting antibodies against swine influenza and Hong Kong influenza viruses in swine sera in the USA*

Pirtle, E. C.; Hill, H. R.; Swanson, M. R.; Van Deusen, R. A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em //1976 EN
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Previous reports have established that swine in the midwestern states of the USA have a high incidence of classical swine influenza and that swine become infected with Hong Kong-like influenza viruses when these are prevalent in the human population. This investigation was undertaken to estimate, on the basis of 2245 sera collected randomly from swine going to slaughter in the USA during the summer months of 1974, how many of the animals had haemagglutination-inhibiting (HI) antibodies against swine influenza and Hong Kong influenza viruses. Based on HI titres of 20 or greater, our serological survey revealed that swine influenza virus infection was widespread throughout the USA, since 20.45% of the sera tested had positive HI titres. However, serological evidence of infection of swine with Hong Kong-like viruses was present in only 2.63% of the sera tested.

Predictors of indoor absolute humidity and estimated effects on influenza virus survival in grade schools

Koep, Tyler H; Enders, Felicity T; Pierret, Chris; Ekker, Stephen C; Krageschmidt, Dale; Neff, Kevin L; Lipsitch, Marc; Shaman, Jeffrey; Huskins, W Charles
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artigo de Revista Científica
EN_US
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Background: Low absolute humidity (AH) has been associated with increased influenza virus survival and transmissibility and the onset of seasonal influenza outbreaks. Humidification of indoor environments may mitigate viral transmission and may be an important control strategy, particularly in schools where viral transmission is common and contributes to the spread of influenza in communities. However, the variability and predictors of AH in the indoor school environment and the feasibility of classroom humidification to levels that could decrease viral survival have not been studied. Methods: Automated sensors were used to measure temperature, humidity and CO2 levels in two Minnesota grade schools without central humidification during two successive winters. Outdoor AH measurements were derived from the North American Land Data Assimilation System. Variability in indoor AH within classrooms, between classrooms in the same school, and between schools was assessed using concordance correlation coefficients (CCC). Predictors of indoor AH were examined using time-series Auto-Regressive Conditional Heteroskedasticity models. Classroom humidifiers were used when school was not in session to assess the feasibility of increasing indoor AH to levels associated with decreased influenza virus survival...

Guillain-Barré Syndrome, Influenza Vaccination, and Antecedent Respiratory and Gastrointestinal Infections: A Case-Centered Analysis in the Vaccine Safety Datalink, 2009–2011

Greene, Sharon K.; Rett, Melisa D.; Vellozzi, Claudia; Li, Lingling; Kulldorff, Martin; Marcy, S. Michael; Daley, Matthew F.; Belongia, Edward A.; Baxter, Roger; Fireman, Bruce H.; Jackson, Michael L.; Omer, Saad B.; Nordin, James D.; Jin, Robert; Weintra
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
EN_US
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Background: Guillain-Barré Syndrome (GBS) can be triggered by gastrointestinal or respiratory infections, including influenza. During the 2009 influenza A (H1N1) pandemic in the United States, monovalent inactivated influenza vaccine (MIV) availability coincided with high rates of wildtype influenza infections. Several prior studies suggested an elevated GBS risk following MIV, but adjustment for antecedent infection was limited. Methods: We identified patients enrolled in health plans participating in the Vaccine Safety Datalink and diagnosed with GBS from July 2009 through June 2011. Medical records of GBS cases with 2009–10 MIV, 2010–11 trivalent inactivated influenza vaccine (TIV), and/or a medically-attended respiratory or gastrointestinal infection in the 1 through 141 days prior to GBS diagnosis were reviewed and classified according to Brighton Collaboration criteria for diagnostic certainty. Using a case-centered design, logistic regression models adjusted for patient-level time-varying sources of confounding, including seasonal vaccinations and infections in GBS cases and population-level controls. Results: Eighteen confirmed GBS cases received vaccination in the 6 weeks preceding onset, among 1.27 million 2009–10 MIV recipients and 2.80 million 2010–11 TIV recipients. Forty-four confirmed GBS cases had infection in the 6 weeks preceding onset...

Comparison of Human-Like H1 (Cluster) Influenza A Viruses in the Swine Host.

ZANELLA, J. R. C.; VINCENT, A. L.; ZANELLA, E. L.; LORUSSO, A.; LOVING, C. L.; BROCKMEIER, S. L.; GAUGER, P. C.; JANKE, B. H.; GRAMER, M. R.
Fonte: Influenza Research and Treatment, v. 2012, p. 1-10, 2012. Publicador: Influenza Research and Treatment, v. 2012, p. 1-10, 2012.
Tipo: Artigo em periódico indexado (ALICE)
PT_BR
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2012; Projeto: 03.09.00.046.

Moderate influenza vaccine effectiveness in Victoria, Australia, 2011

Fielding, J E; Grant, K A; Tran, T; Kelly, H A
Fonte: European Centre for Disease Prevention and Control Publicador: European Centre for Disease Prevention and Control
Tipo: Artigo de Revista Científica Formato: 5 pages
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We used a sentinel general practitioner (GP) network to conduct surveillance for laboratory-confirmed influenza amongst patients presenting with influenza-like illness (ILI) in Victoria, Australia in 2011. The test-negative variation of the case control study design was used to estimate effectiveness for seasonal trivalent influenza vaccine. Cases and controls were ILI patients that tested positive and negative for influenza, respectively. Vaccination status was recorded by GPs and vaccine effectiveness (VE) was calculated as (1-adjusted odds ratio)x100%. There were 529 patients included in the study, of which 29% were influenza-positive. Twelve percent of study participants were reported as vaccinated, 6% of cases and 15% of controls. Adjusted VE against all influenza was 56%, but not statistically significant. There was generally little variation in VE estimates when stratified by virus type and subtype, which is consistent with good matches between circulating strains and the vaccine strains. The VE was higher among adults of working age than among children.

Continued dominance of pandemic A(H1N1) 2009 influenza in Victoria, Australia in 2010.

Grant, K; Franklin, L; Kaczmarek, M; Hurt, A; Kostecki, R; Kelly, H; Fielding, J
Fonte: World Health Organization Publicador: World Health Organization
Tipo: Artigo de Revista Científica Formato: 9 pages
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The 2010 Victorian influenza season was characterized by normal seasonal influenza activity and the dominance of the pandemic A(H1N1) 2009 strain. General Practice Sentinel Surveillance rates peaked at 9.4 ILI cases per 1000 consultations in week 36 for metropolitan practices, and at 10.5 ILI cases per 1000 in the following week for rural practices. Of the 678 ILI cases, 23% were vaccinated, a significantly higher percentage than in previous years. A significantly higher percentage of ILI patients were swabbed in 2010 compared to 2003-2008, but similar to 2009, with a similar percentage being positive for influenza as in previous years. Vaccination rates increased with patient age. Melbourne Medical Deputising Service rates peaked in week 35 at 19.1 ILI cases per 1000 consultations. Of the 1914 cases of influenza notified to the Department of Health, Victoria, 1812 (95%) were influenza A infections - 1001 (55%) pandemic A(H1N1) 2009, 4 (< 1%) A(H3N2) and 807 (45%) not subtyped; 88 (5%) were influenza B; and 14 (< 1%) were influenza A and B co-infections. The World Health Organization Collaborating Centre for Reference and Research on Influenza tested 403 isolates of which 261 were positive for influenza, 250 of which were influenza A and 11 were influenza B. Ninety-two per cent of the influenza A viruses were pandemic A(H1N1) 2009...

Sialic acid receptor detection in the human respiratory tract: evidence for widespread distribution of potential binding sites for human and avian influenza viruses

Nicholls, J.; Bourne, A.; Chen, H.; Guan, Y.; Peiris, J.
Fonte: BioMed Central Ltd. Publicador: BioMed Central Ltd.
Tipo: Artigo de Revista Científica
Publicado em //2007 EN
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Background: Influenza virus binds to cell receptors via sialic acid (SA) linked glycoproteins. They recognize SA on host cells through their haemagglutinins (H). The distribution of SA on cell surfaces is one determinant of host tropism and understanding its expression on human cells and tissues is important for understanding influenza pathogenesis. The objective of this study therefore was to optimize the detection of α2,3-linked and α2,6-linked SA by lectin histochemistry by investigating the binding of Sambucus nigra agglutinin (SNA) for SAα2,6Gal and Maackia amurensis agglutinin (MAA) for SAα2,3Gal in the respiratory tract of normal adults and children. Methods: We used fluorescent and biotinylated SNA and MAA from different suppliers on archived and prospectively collected biopsy and autopsy specimens from the nasopharynx, trachea, bronchus and lungs of fetuses, infants and adults. We compared different methods of unmasking for tissue sections to determine if these would affect lectin binding. Using serial sections we then compared the lectin binding of MAA from different suppliers. Results: We found that unmasking using microwave treatment in citrate buffer produced increased lectin binding to the ciliated and glandular epithelium of the respiratory tract. In addition we found that there were differences in tissue distribution of the α2...

Safety and immunogenicity of concurrent administration of live attenuated influenza vaccine with Measles-Mumps-Rubella and varicella vaccines to infants 12 to 15 months of age

Nolan, T.; Bernstein, D.; Block, S.; Hilty, M.; Keyserling, H.; Marchant, C.; Marshall, H.; Richmond, P.; Yogev, R.; Cordova, J.; Cho, I.; Mendelman, P.
Fonte: Amer Acad Pediatrics Publicador: Amer Acad Pediatrics
Tipo: Artigo de Revista Científica
Publicado em //2008 EN
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OBJECTIVE: This study evaluated the safety, tolerability, and immunogenicity of live attenuated influenza vaccine administered concurrently with measles-mumps-rubella vaccine and varicella vaccine to healthy children 12 to 15 months of age. METHODS: Children were assigned randomly to receive (1) measles-mumps-rubella vaccine, varicella vaccine, and intranasal placebo on day 0, followed by 1 dose of live attenuated influenza vaccine on days 42 and 72; (2) measles-mumps-rubella, varicella, and live attenuated influenza vaccines on day 0, followed by a second dose of live attenuated influenza vaccine on day 42 and intranasally administered placebo on day 72; or (3) 1 dose of live attenuated influenza vaccine on days 0 and 42, followed by measles-mumps-rubella and varicella vaccines on day 72. Serum samples were collected before vaccination on days 0, 42, and 72. Reactogenicity events and adverse events were collected through day 41 after concurrent vaccinations and through day 10 after administration of live attenuated influenza vaccine or placebo alone. RESULTS: Among 1245 (99.5%) evaluable children, seroresponse rates and geometric mean titers for measles-mumps-rubella vaccine and varicella vaccine were similar with concurrent administration of live attenuated influenza vaccine or placebo (seroresponse rates of > or = 96% for measles-mumps-rubella vaccine and > or = 82% for varicella vaccine in both groups). Hemagglutinin-inhibiting antibody geometric mean titers and seroconversion rates to influenza strains in live attenuated influenza virus vaccine were similar after the vaccine was administered alone (seroconversion rates of 98%...

Pandemic influenza and community preparedness

Marshall, H.; Ryan, P.; Roberton, D.; Street, J.; Watson, M.
Fonte: Amer Public Health Assoc Inc Publicador: Amer Public Health Assoc Inc
Tipo: Artigo de Revista Científica
Publicado em //2009 EN
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Objectives. We aimed to examine community knowledge about and attitudes toward the threat of pandemic influenza and assess the community acceptability of strategies to reduce its effect. Methods. We conducted computer-aided telephone interviews in 2007 with a cross-sectional sample of rural and metropolitan residents of South Australia. Results. Of 1975 households interviewed, half (50.2%) had never heard of pandemic influenza or were unaware of its meaning. Only 10% of respondents were extremely concerned about the threat of pandemic influenza. Respondents identified children as the highest priority for vaccination, if supplies were limited; they ranked politicians and teachers as the lowest priority. Although only 61.7% of respondents agreed with a policy of home isolation, 98.2% agreed if it was part of a national strategy. Respondents considered television to be the best means of educating the community. Conclusions. Community knowledge about pandemic influenza is poor despite widespread concern. Public education about pandemic influenza is essential if strategies to reduce the impact of the disease are to be effective.; Helen Marshall, Philip Ryan, Don Roberton, Jackie Street, and Maureen Watson

Immunogenicity of a monovalent 2009 influenza A(H1N1) vaccine in infants and children: A randomized trial

Nolan, T.; McVernon, J.; Skeljo, M.; Richmond, P.; Wadia, U.; Lambert, S.; Nissen, M.; Marshall, H.; Booy, R.; Heron, L.; Hartel, G.; Lai, M.; Basser, R.; Gittleson, C.; Greenberg, M.
Fonte: Amer Medical Assoc Publicador: Amer Medical Assoc
Tipo: Artigo de Revista Científica
Publicado em //2010 EN
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Context: In the ongoing influenza pandemic, a safe and effective vaccine against 2009 influenza A(H1N1) is needed for infants and children. Objective: To assess the immunogenicity and safety of a 2009 influenza A(H1N1) vaccine in children. Design, Setting, and Participants: Randomized, observer-blind, age-stratified, parallel group study assessing 2 doses of an inactivated, split-virus 2009 influenza A(H1N1) vaccine in 370 healthy infants and children aged 6 months to less than 9 years living in Australia. Intervention: Intramuscular injection of 15 µg or 30 µg of hemagglutinin antigen dose of monovalent, unadjuvanted 2009 influenza A(H1N1) vaccine in a 2-dose regimen, administered 21 days apart. Main Outcome Measures: Hemagglutination inhibition assay to estimate the proportion of participants with antibody titers of 1:40 or greater, seroconversion, or a significant antibody titer increase, and factor increase in geometric mean titer. Assessments of solicited adverse events during 7 days and unsolicited adverse events for 21 days after each vaccination. Results: Following the first dose of vaccine, antibody titers of 1:40 or greater were observed in 161 of 174 infants and children in the 15-µg group (92.5%; 95% confidence interval [CI]...

Diversity and clonotypic composition of influenza-specific CD8⁺ TCR repertoires remain unaltered in the absence of Aire; Diversity and clonotypic composition of influenza-specific CD8(+) TCR repertoires remain unaltered in the absence of Aire

Kedzierska, K.; Valkenburg, S.; Guillonneau, C.; Hubert, F.X.; Cukalac, T.; Curtis, J.; Stambas, J.; Scott, H.; Kedzierski, L.; Venturi, V.; Davenport, M.
Fonte: Wiley-V C H Verlag GMBH Publicador: Wiley-V C H Verlag GMBH
Tipo: Artigo de Revista Científica
Publicado em //2010 EN
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TCR repertoire diversity is important for the protective efficacy of CD8(+) T cells, limiting viral escape and cross-reactivity between unrelated epitopes. The exact mechanism for selection of restricted versus diverse TCR repertoires is far from clear, although one thought is that the epitopes resembling self-peptides might select a limited array of TCR due to the deletion of autoreactive TCR. The molecule Aire promotes the expression of tissue-specific Ag on thymic medullary epithelial cells and the deletion of autoreactive cells, and in the absence of Aire autoreactive cells persist. However, the contribution of Aire-dependent peptides to the selection of the Ag-specific TCR repertoire remains unknown. In this study, we dissect restricted (D(b)NP(366)%(+)CD8(+)) and diverse (D(b)PA(224)%(+)CD8(+), K(d)NP(147)%(+)CD8(+)) TCR repertoires responding to three influenza-derived peptides in Aire-deficient mice on both B6 and BALB/c backgrounds. Our study shows that the number, qualitative characteristics and TCR repertoires of all influenza-specific, D(b)NP(366)%(+)CD8(+), D(b)PA(224)%(+)CD8(+) and K(d)NP(147)%(+)CD8(+) T cells are not significantly altered in the absence of Aire. This provides the first demonstration that the selection of an Ag-specific T-cell repertoire is not significantly perturbed in the absence of Aire.; Katherine Kedzierska...

Parental views on vaccine safety and future vaccinations of children who experienced an adverse event following routine or seasonal influenza vaccination in 2010

Parrella, A.; Gold, M.; Marshall, H.; Braunack-Mayer, A.; Watson, M.; Baghurst, P.
Fonte: Landes Bioscience Publicador: Landes Bioscience
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
Relevância na Pesquisa
46.01%
To assess parental vaccine safety views and future vaccination decisions after an adverse event following immunization (AEFI) experienced by their child. A cross-sectional telephone survey was conducted of parents of children aged 0–7 y, identified in AEFI reports submitted to the South Australian Immunization Section, Department Health. The reports included childhood National Immunization Program (NIP), seasonal or pandemic influenza vaccines. Interviews were conducted following a national suspension of the 2010 seasonal trivalent influenza (STIV) vaccine. Parental attitudes toward vaccine safety, reasons for reporting the AEFI and impact on future vaccination intent were assessed. Of 179 parents interviewed, 88% were confident in the safety of vaccines in general. Parents reporting an AEFI to the STIV were more likely to state the event had influenced future vaccination decisions than the NIP vaccine reporters (65% vs 14%, p < 0.001), with 63% stating refusal or hesitance to re-vaccinate their children against influenza. Media reports of the 2010 STIV program suspension was the most common reason for reporting an AEFI for parents of children who received an influenza vaccination. The AEFI experience did not impact on parental decision to continue with routine childhood NIP schedules...

Neurologic complications of influenza A(H1N1)pdm09: surveillance in 6 pediatric hospitals

Khandaker, G.; Zurynski, Y.; Buttery, J.; Marshall, H.; Richmond, P.; Dale, R.; Royle, J.; Gold, M.; Snelling, T.; Whitehead, B.; Jones, C.; Heron, L.; McCaskill, M.; Macartney, K.; Elliott, E.; Booy, R.
Fonte: Lippincott Williams & Wilkins Publicador: Lippincott Williams & Wilkins
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
Relevância na Pesquisa
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OBJECTIVE: We sought to determine the range and extent of neurologic complications due to pandemic influenza A (H1N1) 2009 infection (pH1N1′09) in children hospitalized with influenza. METHODS: Active hospital-based surveillance in 6 Australian tertiary pediatric referral centers between June 1 and September 30, 2009, for children aged <15 years with laboratory-confirmed pH1N1′09. RESULTS: A total of 506 children with pH1N1′09 were hospitalized, of whom 49 (9.7%) had neurologic complications; median age 4.8 years (range 0.5–12.6 years) compared with 3.7 years (0.01–14.9 years) in those without complications. Approximately one-half (55.1%) of the children with neurologic complications had preexisting medical conditions, and 42.8% had preexisting neurologic conditions. On presentation, only 36.7% had the triad of cough, fever, and coryza/runny nose, whereas 38.7% had only 1 or no respiratory symptoms. Seizure was the most common neurologic complication (7.5%). Others included encephalitis/encephalopathy (1.4%), confusion/disorientation (1.0%), loss of consciousness (1.0%), and paralysis/Guillain-Barré syndrome (0.4%). A total of 30.6% needed intensive care unit (ICU) admission, 24.5% required mechanical ventilation, and 2 (4.1%) died. The mean length of stay in hospital was 6.5 days (median 3 days) and mean ICU stay was 4.4 days (median 1.5 days). CONCLUSIONS: Neurologic complications are relatively common among children admitted with influenza...

Influenza surveillance in Victoria, 2006

Fielding, J.; Miller, E.; Adams, J.; Hawking, B.; Grant, K.; Kelly, H.
Fonte: Australian Govt Dept Health and Ageing, Office of Health Protection, Surveillance Branch Publicador: Australian Govt Dept Health and Ageing, Office of Health Protection, Surveillance Branch
Tipo: Artigo de Revista Científica
Publicado em //2007 EN
Relevância na Pesquisa
45.97%
The Victorian influenza season in 2006 remained within normal seasonal activity thresholds and was relatively mild compared with recent years. The season peaked in mid-August, with influenza-like illness (ILI) rates from general practitioner sentinel surveillance and the Melbourne Medical Locum Service (MMLS), and cases of laboratory-confirmed influenza notified to the Department of Human Services, reaching their zeniths within one week of each other. A total of 74 general practitioners (GPs) participated in the sentinel surveillance in 2006, reporting a total of 136,732 consultations during the surveillance period from May to September inclusive. Participating GPs reported a total of 765 patients with an ILI; an average ILI rate of 5.6 cases per 1,000 consultations. The average ILI rate from the MMLS in the same period was 8.5 cases per 1,000 call-outs. Eighty-two per cent of laboratory-confirmed influenza notifications during the surveillance period were type A; the remainder were type B. Typing indicated circulation of two predominant strains during the season: A/Wisconsin/67/2005(H3N2)-like virus and B/Malaysia/2506/2004-like virus. The influenza vaccine for 2006 contained A/New Caledonia/20/99(H1N1)-like virus, A/California/7/2004(H3N2)-like virus and B/Malaysia/2506/2004-like virus. Commun Dis Intell 2007;31:100–106.; James E Fielding...

Clinical epidemiology and predictors of outcome in children hospitalised with influenza A(H1N1)pdm09 in 2009: a prospective national study

Khandaker, G.; Zurynski, Y.; Ridley, G.; Buttery, J.; Marshall, H.; Richmond, P.C.; Royle, J.; Gold, M.; Walls, T.; Whitehead, B.; McIntyre, P.; Wood, N.; Booy, R.; Elliott, E.J.
Fonte: John Wiley & Sons Publicador: John Wiley & Sons
Tipo: Artigo de Revista Científica
Publicado em //2014 EN
Relevância na Pesquisa
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BACKGROUND: There are few large-scale, prospective studies of influenza A(H1N1)pdm09 in children that identify predictors of adverse outcomes. OBJECTIVES: We aimed to examine clinical epidemiology and predictors for adverse outcomes in children hospitalised with influenza A(H1N1)pdm09 in Australia. METHODS: Active hospital surveillance in six tertiary paediatric referral centres (June-September, 2009). All children aged <15 years admitted with laboratory-confirmed influenza A(H1N1)pdm09 were studied. RESULTS: Of 601 children admitted with laboratory-confirmed influenza, 506 (84·2%) had influenza A(H1N1)pdm09. Half (51·0%) of children with influenza A(H1N1)pdm09 were previously healthy. Hospital stay was longer in children with pre-existing condition (mean 6·9 versus 4·9 days; P = 0·02) as was paediatric intensive care unit (PICU) stay (7·0 versus 2·3 days; P = 0·005). Rapid diagnosis decreased both antibiotic use and length of hospital and PICU stay. Fifty (9·9%) children were admitted to a PICU, 30 (5·9%) required mechanical ventilation and 5 (0·9%) died. Laboratory-proven bacterial co-infection and chronic lung disease were significant independent predictors of PICU admission (OR 6·89, 95% CI 3·15-15·06 and OR 3·58...

Global update on the susceptibility of humam influenza viruses to neuraminidase inhibitors 2012-2013

Meijer, A.; Rebelo-de-Andrade, H.; Correia, V.; Besselaar, T.; Drager-Dayal, R.; Fry, A.; Gregory, V.; Gubareva, L.; Kageyama, T.; Lankenby, A.; Lo, J.; Odagiri, T.; Pereyaslov, D.; Siqueira, M.; Takashita, E.; Tashiro, M.; Wang, D.; Wong, S.; Zhang, W.;
Fonte: Elsevier Masson/ International Society for Antiviral Research Publicador: Elsevier Masson/ International Society for Antiviral Research
Tipo: Artigo de Revista Científica
Publicado em /10/2014 ENG
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Emergence of influenza viruses with reduced susceptibility to neuraminidase inhibitors (NAIs) is sporadic, often follows exposure to NAIs, but occasionally occurs in the absence of NAI pressure. The emergence and global spread in 2007/2008 of A(H1N1) influenza viruses showing clinical resistance to oseltamivir due to neuraminidase (NA) H275Y substitution, in the absence of drug pressure, warrants continued vigilance and monitoring for similar viruses. Four World Health Organization (WHO) Collaborating Centres for Reference and Research on Influenza and one WHO Collaborating Centre for the Surveillance, Epidemiology and Control of Influenza (WHO CCs) tested 11,387 viruses collected by WHO-recognized National Influenza Centres (NIC) between May 2012 and May 2013 to determine 50% inhibitory concentration (IC50) data for oseltamivir, zanamivir, peramivir and laninamivir. The data were evaluated using normalized IC50 fold-changes rather than raw IC50 data. Nearly 90% of the 11,387 viruses were from three WHO regions: Western Pacific, the Americas and Europe. Only 0.2% (n=27) showed highly reduced inhibition (HRI) against at least one of the four NAIs, usually oseltamivir, while 0.3% (n=39) showed reduced inhibition (RI). NA sequence data...

Nosocomial vs community-acquired pandemic influenza A (H1N1) 2009: a nested case-control study

Khandaker, G.; Rashid, H.; Zurynski, Y.; Richmond, P.; Buttery, J.; Marshall, H.; Gold, M.; Walls, T.; Whitehead, B.; Elliott, E.; Booy, R.
Fonte: W B Saunders Co Ltd Publicador: W B Saunders Co Ltd
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
Relevância na Pesquisa
46.13%
BACKGROUND: The characteristics of nosocomial influenza in children are not well described. AIM: To compare the characteristics of nosocomial and community-acquired pandemic influenza A (H1N1) 2009 (pH1N1) in Australian children. METHODS: In a nested case-control study, the clinical and epidemiological features of nosocomial vs community-acquired pH1N1 were compared among hospitalized children aged <15 years in six paediatric hospitals in Australia between 1 June and 30 September 2009. FINDINGS: Of 506 hospitalized children with pH1N1, 47 (9.3%) were of nosocomial origin. These 47 cases were compared with 141 gender- and age-matched controls. Cases had a significantly higher proportion of underlying medical conditions compared with controls (81% vs 42%, P < 0.001), and were more likely to be exposed to household smokers (36% vs 20%, P = 0.02). Fewer children with nosocomial influenza presented with classical symptoms of influenza, including subjective fever and lethargy. A higher proportion of children with nosocomial influenza received treatment with oseltamivir (77% vs 43%, P < 0.001), and they required a longer stay in hospital following the onset of influenza (mean 8.5 days vs 4.5 days, P = 0.006). Three children (2%) in the community-acquired group died of pH1N1...

Serological Response in RT-PCR Confirmed H1N1-2009 Influenza A by Hemagglutination Inhibition and Virus Neutralization Assays: An Observational Study

Chen, Mark I.; Barr, Ian G.; Koh, Gerald C. H.; Lee, Vernon J.; Lee, Caroline P. S.; Shaw, Robert; Lin, Cui; Yap, Jonathan; Cook, Alex R.; Tan, Boon Huan; Loh, Jin Phang; Barkham, Timothy; Chow, Vincent T. K.; Lin, Raymond T. P.; Leo, Yee-Sin
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
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BACKGROUND We describe the serological response following H1N1-2009 influenza A infections confirmed by reverse-transcriptase polymerase chain reaction (RT-PCR). METHODOLOGY AND PRINCIPAL FINDINGS The study included patients admitted to hospital, subjects of a seroepidemiologic cohort study, and participants identified from outbreak studies in Singapore. Baseline (first available blood sample) and follow-up blood samples were analyzed for antibody titers to H1N1-2009 and recently circulating seasonal influenza A virus strains by hemagglutination inhibition (HI) and virus micro-neutralization (VM) assays. 267 samples from 118 cases of H1N1-2009 were analyzed. Geometric mean titers by HI peaked at 123 (95% confidence interval, CI 43-356) between days 30 to 39. The chance of observing seroconversion (four-fold or greater increase of antibodies) was maximized when restricting analysis to 45 participants with baseline sera collected within 5 days of onset and follow-up sera collected 15 or more days after onset; for these participants, 82% and 89% seroconverted to A/California/7/2009 H1N1 by HI and VM respectively. A four-fold or greater increase in cross-reactive antibody titers to seasonal A/Brisbane/59/2007 H1N1, A/Brisbane/10/2007 H3N2 and A/Wisconsin/15/2009 H3N2 occurred in 20%...

Antigenic maps of influenza A/H3N2 virus produced with human antisera obtained after primary infection

Fonville, Judith M.; Fraaij, Pieter L. A.; de Mutsert, Gerrie; Wilks, Samuel. H.; van Beek, Ruud; Fouchier, Ron A. M.; Rimmelzwaan, Guus F.
Fonte: Oxford Journals Publicador: Oxford Journals
Tipo: Article; published version
EN
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This is the final version of the article. It first appeared from Oxford University Press via http://dx.doi.org/10.1093/infdis/jiv367; Background: Antigenic characterization of influenza viruses is typically based on hemagglutination inhibition (HI) assay data of viral isolates tested against strain-specific post-infection ferret antisera. Here, similar virus characterizations were performed using first-infection human rather than ferret serology data. Methods: We screened sera collected between 1995 and 2011 from children between 9 and 24 months of age for influenza virus antibodies, performed HI tests for the positive sera against 24 influenza viruses isolated between 1989 and 2011, and measured HI titers of 24 A/H3N2 ferret sera against the same panel of viruses. Results: Of the 17 positive human sera, 6 were high-responders, showing HI patterns that would be expected from primary infection antisera, while 11 sera had lower, more dispersed patterns of reactivity that are not easily explained. The antigenic map based on the high-responder human HI data was similar to the results using ferret data. Conclusions: Although the overall structure of the ferret and human antigenic maps is similar, local differences in virus positions indicate that the human and ferret immune system might see antigenic properties of viruses differently. Further studies are needed to establish to what degree of detail ferret data provide equivalent patterns to human serological reactivity.; This work was supported by the award of a Fellowship in Biomedical Informatics from the Medical Research Council UK [grant number MR/K021885/1] and a Junior Research Fellowship from Homerton College Cambridge to J.M.F.; a Medical Research Council UK studentship [number MR/K50127X/1 to S.H.W.]; the EU FP7 project PREPARE [grant number 602525 to P.L.A.F.]; the National Institute of Allergy and Infectious Diseases...