influenza A Research Papers - Academia.edu (original) (raw)

A real time RT-PCR, using the LightCycler, was developed and compared with rapid antigen enzyme immunoassay (AgEIA) and enhanced virus culture for rapid detection of influenza A viruses in stored and prospectively collected respiratory... more

A real time RT-PCR, using the LightCycler, was developed and compared with rapid antigen enzyme immunoassay (AgEIA) and enhanced virus culture for rapid detection of influenza A viruses in stored and prospectively collected respiratory specimens. Specific hybridization probes were used for simultaneous detection and differentiation between H1N1 and H3N2 subtypes. The sensitivity of the RT-PCR for influenza A H1N1 was 120 copies and H3N2 350 copies of in vitro transcribed RNA. A specimen was considered positive for influenza A when it was culture positive or at least two methods yielded a positive test result. Using these criteria, with stored samples, the RT-PCR sensitivity, specificity, positive and negative predictive values were 82.9, 95.5, 98.9 and 52.5%, respectively. In specimens collected prospectively the RT-PCR sensitivity, specificity, positive and negative predictive values were 100, 87.9, 82.8 and 100%, respectively. There was complete concordance with subtype differentiation by hybridization probe melting temperature analysis and haemagglutination inhibition assay.

The NS1 protein is the only nonstructural protein encoded by influenza A virus. It has been proposed that the NS1 performs several regulatory functions during the viral replication cycle, including the regulation of synthesis, transport,... more

The NS1 protein is the only nonstructural protein encoded by influenza A virus. It has been proposed that the NS1 performs several regulatory functions during the viral replication cycle, including the regulation of synthesis, transport, splicing, and translation of mRNAs. Through the use of reverse genetics, a viable transfectant influenza A virus (delNS1) which lacks the NS1 gene has been generated. Our results indicate that the NS1 of influenza A virus is an auxiliary (virulence) factor which plays a crucial role in inhibiting interferon-mediated antiviral responses of the host.

During the 2002/2003 season, Italian sentinel-based network for surveillance of influenza, coordinated by Inter-university (Genoa-Milan-Trieste) Centre for Influenza Research (CIRI) registered an increasing incidence from week 9/2003... more

During the 2002/2003 season, Italian sentinel-based network for surveillance of influenza, coordinated by Inter-university (Genoa-Milan-Trieste) Centre for Influenza Research (CIRI) registered an increasing incidence from week 9/2003 (10.3 cases per 1000). The ...

Avian influenza viruses (AIVs) are pathogens of global concern, but there has been little previous research on avian influenza in southern Africa and almost nothing is known about the dynamics of AIVs in the region. We counted, captured... more

Avian influenza viruses (AIVs) are pathogens of global concern, but there has been little previous research on avian influenza in southern Africa and almost nothing is known about the dynamics of AIVs in the region. We counted, captured and sampled birds regularly at five sites, two in South Africa (Barberspan and Strandfontein) and one in each of Botswana (Lake Ngami), Mozambique (Lake Chuali) and Zimbabwe (Lakes Manyame and Chivero) between March 2007 and May 2009. The South African and Zimbabwean sites were visited every 2 months and the sites in Botswana and Mozambique every 4 months. During each visit we undertook 5–7 days of standardised bird counts followed by 5–10 days of capturing and sampling water-associated birds. We sampled 4,977 birds of 165 different species and completed 2,503 half-hour point counts. We found 125 positive rRT-PCR cases of avian influenza across all sites. Two viruses (H1N8 and H3N8) were isolated and additional H5, H6 and H7 strains were identified. We did not positively identify any highly pathogenic H5N1. Overall viral prevalence (2.51%) was similar to the lower range of European values, considerable spatial and temporal variation occurred in viral prevalence, and there was no detectable influence of the annual influx of Palearctic migrants. Although waterbirds appear to be the primary viral carriers, passerines may link wild birds and poultry. While influenza cycles are probably driven by the bird movements that result from rainfall patterns, the epidemiology of avian influenza in wild birds in the subregion is complex and there appears to be the possibility for viral transmission throughout the year.

Influenza contributes significantly to morbidity and mortality in the winter season. The aim of the study was to identify clinical signs and symptoms most predictive of influenza infection in children and adults with influenza-like... more

Influenza contributes significantly to morbidity and mortality in the winter season. The aim of the study was to identify clinical signs and symptoms most predictive of influenza infection in children and adults with influenza-like illness. A prospective systematic sampling analysis of clinical data collected through sentinel surveillance system for influenza in 32 primary care centers and one tertiary care hospital in Slovenia during two consecutive influenza seasons (2004/2005 and 2005/2006) was carried out. Children and adults who had influenza-like illness, defined as febrille illness with sudden onset, prostration and weakness, muscle and joint pain and at least (cough, sore throat, coryza) were included and tested for influenza A and B virus, adenovirus, respiratory syncytial virus and enterovirus by RT-PCR. Clinical data were evaluated in statistical models to identify the best predictors for the confirmation of influenza for children (under age of 15) and adults. Of 1,286 pa...

Neuraminidase is an important target for design of antiviral agents in the prophylaxis and treatment of avian influenza virus infections. We have shown the applicability of computer-assisted combinatorial techniques in the design,... more

Neuraminidase is an important target for design of antiviral agents in the prophylaxis and treatment of avian influenza virus infections. We have shown the applicability of computer-assisted combinatorial techniques in the design, focusing and in silico screening of a virtual library of analogs of oseltamivir (Tamiflu) with the goal to find potent inhibitors of influenza A neuraminidase N1 that fill the cavity found adjacent to the active site. Crystal structure of oseltamivir-N1 complex was used in the structure-based focusing and virtual screening of the designed library. A target-specific Piecewise Linear Potential type 1 scoring function fitted for a training set of 14 carbocyclic inhibitors and validated for three other inhibitors was used to select virtual hits with predicted inhibitory activities in the subnanomolar range. The results of this computational study are useful as a rational guide for synthetic and medicinal chemists who are developing new drugs against the avian influenza virus H5N1.

Recent efforts of health authorities to promote vaccination against influenza A/H1N1 were met with low compliance rates in most industrialized countries. Here we analyzed the attitudes of the Israeli public towards A/H1N1 vaccination... more

Recent efforts of health authorities to promote vaccination against influenza A/H1N1 were met with low compliance rates in most industrialized countries. Here we analyzed the attitudes of the Israeli public towards A/H1N1 vaccination based on a telephone survey conducted several months after the peak of the outbreak. The findings attest to the low uptake of the A/H1N1 vaccine (17%) in Israel, and identify the socio-demographic characteristics associated with non-compliance. In addition, the survey reveals passiveness, fear and distrust as motives leading to non-compliance. Most importantly, the study identified the substantial weight of reflective assessment in the attitude of lay individuals towards the A/H1N1 vaccine. As many as 30% of the non-vaccinated responders provided reasoned arguments for rejecting the vaccine, based mainly on assessment of threat versus actual risk. These observations highlight the need to consider the opinion of the lay public when implementing new vaccination programs.

As part of conservation efforts between 1997 and 2001, more than 25% (332 animals) of the endangered Hawaiian monk seal (Monachus schauinslandi) population was sampled in the northwestern Hawaiian Islands. Serum samples were tested for... more

As part of conservation efforts between 1997 and 2001, more than 25% (332 animals) of the endangered Hawaiian monk seal (Monachus schauinslandi) population was sampled in the northwestern Hawaiian Islands. Serum samples were tested for antibodies to viruses, bacteria, and parasites known to cause morbidity and mortality in other marine mammal species. Antibodies were found to phocine herpesvirus-1 by using

This very short medical communication proposes that potent NRF2-activating dietary supplements (like resveratrol, sulforaphane, curcumin, “Asea redox supplement” [ARS] etc.) should be clinically tested as safe adjuvants (in various... more

This very short medical communication proposes that potent NRF2-activating dietary supplements (like resveratrol, sulforaphane, curcumin, “Asea redox supplement” [ARS] etc.) should be clinically tested as safe adjuvants (in various combinations) in all types of medium and severe cases of aggressive respiratory viral infections (including Influenza A/B/C, SARS, MERS, COVID-19, measles, avian influenza etc., including those patients who have important comorbidities like HIV/AIDS, tuberculosis [TB] etc.) based on their extrapolated cytoprotective antioxidant effects (especially on the main vital organs: brain, heart, lungs, kidneys and liver), including the extrapolated strong cytoprotection offered by ARS on the cardiac muscle of DMD patients (which can be extrapolated to the lungs), like the author of this paper has demonstrated in past papers.
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The recent swine H1N1 influenza outbreak demonstrated that egg-based vaccine manufacturing has an Achille's heel: its inability to provide a large number of doses quickly. Using a novel manufacturing platform based on transient expression... more

The recent swine H1N1 influenza outbreak demonstrated that egg-based vaccine manufacturing has an Achille's heel: its inability to provide a large number of doses quickly. Using a novel manufacturing platform based on transient expression of influenza surface glycoproteins in Nicotiana benthamiana, we have recently demonstrated that a candidate Virus-Like Particle (VLP) vaccine can be generated within 3 weeks of release of sequence information. Herein we report that alum-adjuvanted plant-made VLPs containing the hemagglutinin (HA) protein of H5N1 influenza (A/Indonesia/5/05) can induce cross-reactive antibodies in ferrets. Even low doses of this vaccine prevented pathology and reduced viral loads following heterotypic lethal challenge. We further report on safety and immunogenicity from a Phase I clinical study of the plant-made H5 VLP vaccine in healthy adults 18-60 years of age who received 2 doses 21 days apart of 5, 10 or 20 mg of alum-adjuvanted H5 VLP vaccine or placebo (alum). The vaccine was well tolerated at all doses. Adverse events (AE) were mild-to-moderate and self-limited. Pain at the injection site was the most frequent AE, reported in 70% of vaccinated subjects versus 50% of the placebo recipients. No allergic reactions were reported and the plant-made vaccine did not significantly increase the level of naturally occurring serum antibodies to plant-specific sugar moieties. The immunogenicity of the H5 VLP vaccine was evaluated by Hemagglutination-Inhibition (HI), Single Radial Hemolysis (SRH) and MicroNeutralisation (MN). Results from these three assays were highly correlated and showed similar trends across doses. There was a clear dose-response in all measures of immunogenicity and almost 96% of those in the higher dose groups (2610 or 20 mg) mounted detectable MN responses. Evidence of striking cross-protection in ferrets combined with a good safety profile and promising immunogenicity in humans suggest that plant-based VLP vaccines should be further evaluated for use in pre-pandemic or pandemic situations.

In the United States, preparation for a potential influenza pandemic is receiving heightened media coverage and scrutiny. Scientific attention is focused on the potential for the current Southeastern Asian avian flu virus, influenza A... more

In the United States, preparation for a potential influenza pandemic is receiving heightened media coverage and scrutiny. Scientific attention is focused on the potential for the current Southeastern Asian avian flu virus, influenza A (H5N1), to become a pandemic threat through genetic mutation and viral reassortment. It is imperative that we act now, as we face an evolving and advancing disease state with insufficient national preparation. Existing preparedness plans address laboratory and disease surveillance, community containment and border protection, and mass dispensing and vaccination strategies. However, little attention has been directed to identifying and managing psychological and social factors likely to influence human behavior during a pandemic. All of our health and medical strategies require people to behave in prescribed ways to avoid exposure, prevent infection, or halt disease transmission. This article provides timely expert panel recommendations for pandemic influenza response and recovery by addressing human behavior and adaptation.

The word Influenza comes from mid–18th century Italian and literally means ‘influence’. Similar to how the coronavirus was once best known to cause the common cold, in 1918 Influenza was felt to be so benign a disease that it was not... more

The word Influenza comes from mid–18th century Italian and literally means ‘influence’. Similar to how the coronavirus was once best known to cause the common cold, in 1918 Influenza was felt to be so benign a disease that it was not reportable in the United States. And it was not until 1933 that Influenza was “discovered”. So just what was causing the deaths in 1918? And why did the corona “virus” turn so deadly so quickly? Before we can be certain of anything, these questions need to be answered. But to this point, they have not been answered. In the meantime, during both events there was a deadly pandemic of tuberculosis going on, a pandemic which even in 2020 kills one person every 21 seconds for a total of at least 1.5 to 1.8 million dead in 2018 alone. Yet Robert Koch, TB’s discoverer, was repeatedly forced to call it a virus, to assuage other authorities of his time. And, as we shall soon see, the concept that only a new and virulent strain of a virus can be so infectious and kill so quickly is not only fallacious, but dangerous -and completely at odds with what used to be called the acute form of “galloping consumption” [tuberculosis] which did and still can kill in a matter of hours, days or weeks.
“Viral” influenza was informally first mentioned as being behind America’s 1918 influenza pandemic not by a direct study of the disease in humans, but rather from studies on animal diseases. In 1918, J.S. Koen, a veterinarian, observed a disease killing thousands of pigs which he believed to be the same disease as the now infamous influenza Pandemic of 1918. He felt that it was a virus. It was solely his belief. Yet new evidence and older historical findings bring up the possibility that influenza doesn’t originate from a virus –despite the indefatigable efforts, up to the present, of flu enthusiasts to viralize the 1918-19 pandemic. (Burnet F, Clark E. 1942) (Morens DM, Taubenberger JK. 2009). As we shall see, such efforts on the part of viral devotees are nothing new, and began in force with scant evidence in Great Britain during the 1st World War, also known as the Great War.

We develop a simple ordinary differential equation model to study the epidemiological consequences of the drift mechanism for influenza A viruses. Improving over the classical SIR approach, we introduce a fourth class (C) for the... more

We develop a simple ordinary differential equation model to study the epidemiological consequences of the drift mechanism for influenza A viruses. Improving over the classical SIR approach, we introduce a fourth class (C) for the cross-immune individuals in the population, i.e., those that recovered after being infected by different strains of the same viral subtype in the past years. The SIRC model predicts that the prevalence of a virus is maximum for an intermediate value of R 0 , the basic reproduction number. Via a bifurcation analysis of the model, we discuss the effect of seasonality on the epidemiological regimes. For realistic parameter values, the model exhibits a rich variety of behaviors, including chaos and multistable periodic outbreaks. Comparison with empirical evidence shows that the simulated regimes are qualitatively and quantitatively consistent with reality, both for tropical and temperate countries. We find that the basins of attraction of coexisting cycles can be fractal sets, thus predictability can in some cases become problematic even theoretically. In accordance with previous studies, we find that increasing cross-immunity tends to complicate the dynamics of the system.

S-OIV infection can cause severe illness, the acute respiratory distress syndrome, and death in previously healthy persons who are young to middle-aged. None of the secondary infections among health care workers were severe.

Pseudotype reporter viruses provide a safe, quantitative, and high-throughput tool for assessing antibody neutralization for many viruses, including high pathogenicity H5 and H7 influenza A strains. However, adapting this system to other... more

Pseudotype reporter viruses provide a safe, quantitative, and high-throughput tool for assessing antibody neutralization for many viruses, including high pathogenicity H5 and H7 influenza A strains. However, adapting this system to other influenza subtypes has been hampered by variations in the protease cleavage site of hemagglutinin (HA) that make it less susceptible to the cleavage required for infectivity. In this report several proteases, reporter vectors, and cell substrates were evaluated while optimizing pseudovirus production, and robust methods were established for sensitive and specific neutralization of pseudotypes carrying influenza H1, H3, and H5 subtype HA that correlates well with titers obtained in microneutralization assays involving replicating influenza virus These findings should facilitate broad use of HA-pseudotypes that remove the need for infectious virus in a range of applications, including neutralization assays for serological surveys of viral infection and evaluations of vaccine sera.

At this critical juncture when the world has not yet recovered from the threat of avian infl uenza, the virus has returned in the disguise of swine infl uenza, a lesser known illness common in pigs. It has reached pandemic proportions in... more

At this critical juncture when the world has not yet recovered from the threat of avian infl uenza, the virus has returned in the disguise of swine infl uenza, a lesser known illness common in pigs. It has reached pandemic proportions in a short time span with health personnel still devising ways to identify the novel H1N1 virus and develop vaccines against it. The H1N1 virus has caused a considerable number of deaths within the short duration since its emergence. Presently, there are no effective methods to contain this newly emerged virus. Therefore, a proper and clear insight is urgently required to prevent an outbreak in the future and make preparations that may be planned well in advance. This review is an attempt to discuss the historical perspective of the swine fl u virus, its epidemiology and route of transmission to better understand the various control measures that may be taken to fi ght the danger of a global pandemic. [Khanna M, Gupta N, Gupta A and Vijayan V K 2009 Infl uenza A (H1N1) 2009: a pandemic alarm; J. Biosci. 34 481-489]

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Background: Protective respiratory face masks protect the nose and mouth of the wearer from vapor drops carrying viruses or other infectious pathogens. However, incorrect use and disposal may actually increase the risk of pathogen... more

Background: Protective respiratory face masks protect the nose and mouth of the wearer from vapor drops carrying viruses or other infectious pathogens. However, incorrect use and disposal may actually increase the risk of pathogen transmission, rather than reduce it, especially when masks are used by non-professionals such as the lay public. Copper oxide displays potent antiviral properties. A platform technology has been developed that permanently introduces copper oxide into polymeric materials, conferring them with potent biocidal properties.

We have investigated the influence of Sanicula europaea L. extracts on influenza virus growth in MDCK cells. Fractions I, II, and III separated from Sanicula extract with Sephadex column chromatography were found to be non-toxic against... more

We have investigated the influence of Sanicula europaea L. extracts on influenza virus growth in MDCK cells. Fractions I, II, and III separated from Sanicula extract with Sephadex column chromatography were found to be non-toxic against MDCK cells. The growth of influenza A/PR/8/34 was completely inhibited by these fractions, while that of influenza B/Lee/40 was not affected. Fractions II and III have been shown not to have a direct virucidal activity on influenza A/PR/8/34. Influenza A/Vic/1/75 produced microscopic plaques in the presence of the extract. In vitro RNA synthesis with viral RNA-dependent RNA polymerase was also inhibited by a water soluble extract of Sanicula. These observations suggest that the Sanicula extract contains an anti-influenza virus substance. ᭧

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a b s t r a c t 2009 H1N1 influenza A ("swine flu") vaccine has been offered to healthy UK children aged 6 months-5 years since December 2009, though around 50% of parents plan to reject the vaccine. This study examined whether such... more

a b s t r a c t 2009 H1N1 influenza A ("swine flu") vaccine has been offered to healthy UK children aged 6 months-5 years since December 2009, though around 50% of parents plan to reject the vaccine. This study examined whether such parents exhibit omission bias (preference for errors arising from inaction over errors arising from action). One-hundred and forty-two parents completed an online questionnaire in which they rated (a) probability of occurrence, (b) symptoms and (c) duration of a hypothetical disease and a hypothetical vaccine adverse event (VAE). Almost all attributes were rated significantly less favourably when relating to VAE than to disease (p < 0.01 for 17 of 22 outcomes), despite the attributes being objectively identical. These data suggest that any vaccine is at a disadvantage in many parents' consciousness in comparison with the infection itself, and that minor safety concerns could have disproportionately detrimental effects on vaccine uptake. Behavioural science offers strategies to ameliorate the impact of this bias and these should be explored further.

a b s t r a c t The pandemic virus of 2009 (2009 H1N1) continues to cause illness worldwide, especially in younger age groups. The widespread H1N1 virus infection further emphasizes the need for vaccine strategies that are effective... more

a b s t r a c t The pandemic virus of 2009 (2009 H1N1) continues to cause illness worldwide, especially in younger age groups. The widespread H1N1 virus infection further emphasizes the need for vaccine strategies that are effective against emerging pandemic viruses and are not dependent on the limitations of traditional egg-based technology. This report describes a recombinant influenza virus-like particle (VLP) vaccine consisting of hemagglutinin (HA), neuraminidase (NA), and matrix (M1) proteins of influenza A/California/04/2009 (H1N1) virus. Influenza H1N1 VLPs with a diameter of approximately 120 nm were released into the culture medium from Sf9 insect cells infected with recombinant baculovirus coexpressing HA, NA, and M1 proteins. Purified recombinant H1N1 VLPs morphologically resembled influenza virions and exhibited biological characteristics of influenza virus, including HA and NA activities. In the ferret challenge model, 2009 influenza H1N1 VLPs elicited high-titer serum hemagglutination inhibition (HI) antibodies specific for the 2009 H1N1 virus and inhibited replication of the influenza virus in the upper and lower respiratory tract tissues following A/Mexico/4482/09 (H1N1) virus challenge. Moreover, a single 15 g dose of H1N1 VLPs resulted in complete virus clearance in the ferret lung. These results provide support for the use of recombinant influenza VLP vaccine as an effective strategy against pandemic H1N1 virus.

This review article reports on the newly emerged swine influenza pandemic: a global environemental, medical and public health challenge-should the Nigeria be alarmed? It also examines the features of H1N1, including incidence, infection,... more

This review article reports on the newly emerged swine influenza pandemic: a global environemental, medical and public health challenge-should the Nigeria be alarmed? It also examines the features of H1N1, including incidence, infection, immunity, clinical management, prevention and control, and therapy globally. Swine influenza has emerged as one of the primary public health concern of the 21st century. Swine influenza

A ionization technique in mass spectrometry called Direct Analysis in Real Time Mass Spectrometry (DART TOF-MS) coupled with a Direct Binding Assay was used to identify and characterize anti-viral components of an elderberry fruit... more

A ionization technique in mass spectrometry called Direct Analysis in Real Time Mass Spectrometry (DART TOF-MS) coupled with a Direct Binding Assay was used to identify and characterize anti-viral components of an elderberry fruit (Sambucus nigra L.) extract without either derivatization or separation by standard chromatographic techniques. The elderberry extract inhibited Human Influenza A (H1N1) infection in vitro with an IC 50 value of 252 ± 34 lg/mL. The Direct Binding Assay established that flavonoids from the elderberry extract bind to H1N1 virions and, when bound, block the ability of the viruses to infect host cells. Two compounds were identified, 5,7,3 0 ,4 0 -tetra-O-methylquercetin (1) and 5,7-dihydroxy-4-oxo-2-(3,4,5-trihydroxyphenyl)chroman-3-yl-3,4,5-trihydroxycyclohexanecarboxylate (2), as H1N1-bound chemical species. Compound 1 and dihydromyricetin (3), the corresponding 3-hydroxyflavonone of 2, were synthesized and shown to inhibit H1N1 infection in vitro by binding to H1N1 virions, blocking host cell entry and/or recognition. Compound 1 gave an IC 50 of 0.13 lg/mL (0.36 lM) for H1N1 infection inhibition, while dihydromyricetin (3) achieved an IC 50 of 2.8 lg/mL (8.7 lM). The H1N1 inhibition activities of the elderberry flavonoids compare favorably to the known anti-influenza activities of Oseltamivir (Tamiflu Ò ; 0.32 lM) and Amantadine (27 lM).

Our previous study demonstrated that Melaleuca alternifolia (tea tree) oil (TTO) had an interesting antiviral activity against Influenza A in MDCK cells. In fact, when we tested TTO and some of its components, we found that TTO had an... more

Our previous study demonstrated that Melaleuca alternifolia (tea tree) oil (TTO) had an interesting antiviral activity against Influenza A in MDCK cells. In fact, when we tested TTO and some of its components, we found that TTO had an inhibitory effect on influenza virus replication at doses below the cytotoxic dose; terpinen-4-ol, terpinolene, and alfa-terpineol were the main active components.

Background: Influenza A, including avian influenza, is a major public health threat in developed and developing countries. Rapid and accurate detection is a key component of strategies to contain spread of infection, and the efficient... more

Background: Influenza A, including avian influenza, is a major public health threat in developed and developing countries. Rapid and accurate detection is a key component of strategies to contain spread of infection, and the efficient diagnosis of influenza-like-illness is essential to protect health infrastructure in the event of a major influenza outbreak.

Two new sesquiterpene coumarins, designated 5′-acetoxy-8′-hydroxyumbelliprenin (1) and 10′R-acetoxy-11′-hydroxyumbelliprenin (2), and a new diterpene, 15-hydroxy-6-en-dehydroabietic acid (3), along with 27 known compounds, were isolated... more

Two new sesquiterpene coumarins, designated 5′-acetoxy-8′-hydroxyumbelliprenin (1) and 10′R-acetoxy-11′-hydroxyumbelliprenin (2), and a new diterpene, 15-hydroxy-6-en-dehydroabietic acid (3), along with 27 known compounds, were isolated from a CHCl 3 -soluble extract of Ferula assa-foetida through bioassay-guided fractionation. The structures of the new metabolites 1-3 were identified by spectroscopic data interpretation and by the Mosher ester method. Compounds 4 and 6-13 showed greater potency against influenza A virus (H 1 N 1 ) (IC 50 0.26-0.86 µg/mL) than amantadine (IC 50 0.92 µg/mL), and 11 exhibited the best potency (IC 50 0.51, 2.6, and 3.4 µg/mL) of these compounds against the HepG2, Hep3B, and MCF-7 cancer cell lines, respectively.

The aim of this study was to determine the performance of real-time amplification based methods -NASBA, TaqMan, RT-FRET, and RT-PCR LUXÔ formats -for the detection of influenza A (H5N1) virus RNA. In an analysis of 54 samples obtained... more

The aim of this study was to determine the performance of real-time amplification based methods -NASBA, TaqMan, RT-FRET, and RT-PCR LUXÔ formats -for the detection of influenza A (H5N1) virus RNA. In an analysis of 54 samples obtained from a range of animal species in Thailand during the period 2003-2006, results showed that the NASBA (H5 ¼ 98.2%, N1 ¼ 96.3%), TaqMan (H5 ¼ 98.2%, N1 ¼ 96.3%) and FRET (H5 ¼ 98.2%, N1 ¼ 96.3%) had significantly higher rates of positive detection than LUX (H5 ¼ 94.4%, N1 ¼ 50.0%; P < 0.001) for influenza A, H5 and N1 isolates. There were no false-positive results from any methods used in the negative-control group of samples. The limits of analytical detection were at least 10 copies/reaction in real-time NASBA and LUX assays, while FRET and TaqMan assay appeared to be less sensitive at !100 copies/reaction. The assays were relatively specific without cross-reactivity to a number of other influenza strains or viral pathogens. In conclusion, our study demonstrated that realtime NASBA, TaqMan and FRET assays can be used to detect influenza A (H5N1) from a wide range of hosts, and be specific for H5N1 samples obtained during different outbreaks (2003)(2004)(2005)(2006). All assays provided the benefit of rapid influenza H5N1 identification for early diagnosis, in the range of hours, and they are well suited to high throughput analyses.

The percentage of the world's population living in urban areas will increase from 50% in 2008 to 70% (4.9 billion) in 2025. Crowded urban areas in developing and industrialized countries are uniquely vulnerable to public health crises and... more

The percentage of the world's population living in urban areas will increase from 50% in 2008 to 70% (4.9 billion) in 2025. Crowded urban areas in developing and industrialized countries are uniquely vulnerable to public health crises and face daunting challenges in surveillance, response, and public communication. The revised International Health Regulations require all countries to have core surveillance and response capacity by 2012. Innovative approaches are needed because traditional local-level strategies may not be easily scalable upward to meet the needs of huge, densely populated cities, especially in developing countries. The responses of Mexico City and New York City to the initial appearance of influenza A pandemic (H1N1) 2009 virus during spring 2009 illustrate some of the new challenges and creative response strategies that will increasingly be needed in cities worldwide.

Frente à pandemia causada por um novo vírus, influenza A (H1N1), descrevemos o caso de um paciente de 56 anos com síndrome respiratória aguda grave causada por influenza A (H1N1) sem fatores de risco importantes. Os resultados dos exames... more

Frente à pandemia causada por um novo vírus, influenza A (H1N1), descrevemos o caso de um paciente de 56 anos com síndrome respiratória aguda grave causada por influenza A (H1N1) sem fatores de risco importantes. Os resultados dos exames laboratoriais e de imagem (radiografia e TC de tórax) são apresentados aqui. O paciente teve boa evolução e recebeu alta hospitalar em 14 dias.

An outbreak of highly pathogenic avian influenza A virus subtype H7N7 began in poultry farms in the Netherlands in 2003. Virus infection was detected by RT-PCR in 86 poultry workers and three household contacts of PCR-positive poultry... more

An outbreak of highly pathogenic avian influenza A virus subtype H7N7 began in poultry farms in the Netherlands in 2003. Virus infection was detected by RT-PCR in 86 poultry workers and three household contacts of PCR-positive poultry workers, mainly associated with conjunctivitis. To determine the magnitude of and risk factors for human-to-human transmission of influenza A/H7N7 in the Netherlands, a retrospective cohort study among household members of infected poultry workers was undertaken. In total, 33 (58.9%) of 56 (among 62) participants who provided blood samples had positive H7 serology, using single convalescent serum samples obtained at least 3 weeks after onset of symptoms of the index case. Eight household members (12.9%) reported symptoms (conjunctivitis and/or ILI), of which four of five (80.0%) tested seropositive. On univariate analysis, significant risk factors for seropositivity included having at least two toilets, a pet bird, and using cloth handkerchiefs. It was...

During the 2009 influenza A (H1N1) pandemic several pandemic H1N1 vaccines were licensed using fast track procedures, with relatively limited data on the safety in children and adolescents. Different extensive safety monitoring efforts... more

During the 2009 influenza A (H1N1) pandemic several pandemic H1N1 vaccines were licensed using fast track procedures, with relatively limited data on the safety in children and adolescents. Different extensive safety monitoring efforts were put in place to ensure timely detection of adverse events following immunization. These combined efforts have generated large amounts of data on the safety of the different pandemic H1N1 vaccines, also in children and adolescents. In this overview we shortly summarize the safety experience with seasonal influenza vaccines as a background and focus on the clinical and post marketing safety data of the pandemic H1N1 vaccines in children. We identified 25 different clinical studies including 10,505 children and adolescents, both healthy and with underlying medical conditions, between the ages of 6 months and 23 years. In addition, large monitoring efforts have resulted in large amounts of data, with almost 13,000 individual case reports in children ...

The Influenza A H1N1 2009 pandemic was a test of the global public health response. Strategies that worked included mass vaccine production and antivirals while quarantine and isolation proved futile. Among the lessons learned was the... more

The Influenza A H1N1 2009 pandemic was a test of the global public health response. Strategies that worked included mass vaccine production and antivirals while quarantine and isolation proved futile. Among the lessons learned was the importance of severity in the definition of a pandemic.

Background: The first cases of influenza A/H1N1 (swine flu) were confirmed in the UK on 27th April 2009, after a novel virus first identified in Mexico rapidly evolved into a pandemic. The swine flu outbreak was the first pandemic in more... more

Background: The first cases of influenza A/H1N1 (swine flu) were confirmed in the UK on 27th April 2009, after a novel virus first identified in Mexico rapidly evolved into a pandemic. The swine flu outbreak was the first pandemic in more than 40 years and for many, their first encounter with a major influenza outbreak. This study examines public understandings of the pandemic, exploring how people deciphered the threat and perceived they could control the risks. Methods: Purposive sampling was used to recruit seventy three people (61 women and 12 men) to take part in 14 focus group discussions around the time of the second wave in swine flu cases. Results: These discussions showed that there was little evidence of the public over-reacting, that people believed the threat of contracting swine flu was inevitable, and that they assessed their own self-efficacy for protecting against it to be low. Respondents assessed a greater risk to their health from the vaccine than from the disease. Such findings could have led to apathy about following the UK Governments recommended health protective behaviours, and a sub-optimal level of vaccine uptake. More generally, people were confused about the difference between seasonal influenza and swine flu and their vaccines. Conclusions: This research suggests a gap in public understandings which could hinder attempts to communicate about novel flu viruses in the future. There was general support for the government's handling of the pandemic, although its public awareness campaign was deemed ineffectual as few people changed their current hand hygiene practices. There was less support for the media who were deemed to have over-reported the swine flu pandemic.

The world is currently undergoing a pandemic caused by an H1N1 influenza A virus, the so-called &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;swine... more

The world is currently undergoing a pandemic caused by an H1N1 influenza A virus, the so-called &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;swine flu&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;. The H5N1 (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;bird flu&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;) influenza A viruses, now circulating in Asia, Africa and Europe, are extremely virulent in humans, although they have not so far acquired the ability to transfer efficiently from human to human. These health concerns have spurred considerable interest in understanding the molecular biology of influenza A viruses. Recent structural studies of influenza A virus proteins (or fragments) help enhance our understanding of the molecular mechanisms of the viral proteins and the effects of drug resistance to improve drug design. The structures of domains of the influenza RNA-dependent RNA polymerase and the nonstructural NS1A protein provide opportunities for targeting these proteins to inhibit viral replication.