Influenza Virus Net is the web resource for anyone interested in influenza and flu pandemics. The objectives of Influenza Virus Net are to be the public and professional information resource for influenza and to serve as a network in the exchange of information and news related to influenza.

Influenza, commonly referred to as the flu, is an infectious disease caused by RNA viruses of the family Orthomyxoviridae (the influenza viruses), that affects humans, birds and other mammals. The virus spreads easily from person to person. Influenza circulates worldwide and can affect anybody in any age group. Influenza causes annual epidemics that peak during winter in temperate regions. Influenza is a serious public health problem that causes severe illnesses and deaths for higher risk populations. The most common symptoms of the disease are chills, fever, sore throat, muscle pains, severe headache, coughing, weakness/fatigue and general discomfort. Sore throat, fever and coughs are the most frequent symptoms. In more serious cases, influenza causes pneumonia, which can be fatal, particularly for the young and the elderly. An influenza epidemic can take an economic toll through lost workforce productivity, and strain health services. Vaccination is the most effective way to prevent infection.

• Death toll from new bird flu in China rises to 36 - MSN News
  Sat, 18 May 2013 23:08:
• Puzzling! Swine flu virus detected in elephant seals off West Coast - NBCNews.com (blog)
  Sat, 18 May 2013 20:30:
• New Market Research Report: Influenza - Pipeline Review, H1 2013 - SBWire (press release)
  Sat, 18 May 2013 18:48:
• Bird flu death toll rises in China - MWC News
  Sat, 18 May 2013 17:41:
• Lull in Bird Flu Doesn't Mean the Storm Has Passed - dailyRx
  Sat, 18 May 2013 17:29:
• H7N9 more likely to transmit among humans than other bird flu - Economic Times
  Sat, 18 May 2013 15:45:
• A*STAR and Cytos Bring Singapore's First Influenza Vaccine to Clinical Testing - Stockhouse
  Sat, 18 May 2013 13:07:
• Deaths Due To Bird Flu In China Rises To 36: WHO - IBTimes India
  Sat, 18 May 2013 12:44:
• Chinese Provinces End their Emergency Response to H7N9 Bird Flu - TopNews Arab Emirates
  Sat, 18 May 2013 10:49:
• Woman dies of swine flu in UP - Business Standard
  Sat, 18 May 2013 04:17:

• PRO/AH/EDR> Avian influenza, human (81): China CDC/WHO H7N9 Mission Report
  Sat, 18 May 2013 21:06:38
  Avian Influenza H7N9 — China
  Introduction
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  On [31 Mar 2013], in accordance with the International Health Regulations (2005) [IHR],the Government of China reported the detection of 3 cases of human infection with a novel influenza A(H7N9) virus (hereafter, H7N9) in Shanghai and the province of Anhui. At the same time, the Chinese Center for Disease Control and Prevention (China CDC) posted full genome sequences of viruses isolated from the 1st 3 cases in a publicly accessible database. Over the next 2 weeks
• PRO/AH/EDR> Avian influenza, human (81): China CDC/WHO H7N9 Mission Report
  Sat, 18 May 2013 21:06:38
  Avian Influenza H7N9 — United States
  Introduction
  -----------
  On [31 Mar 2013], in accordance with the International Health Regulations (2005) [IHR],the Government of China reported the detection of 3 cases of human infection with a novel influenza A(H7N9) virus (hereafter, H7N9) in Shanghai and the province of Anhui. At the same time, the Chinese Center for Disease Control and Prevention (China CDC) posted full genome sequences of viruses isolated from the 1st 3 cases in a publicly accessible database. Over the next 2 weeks

• Influenza evolution navigates stability valleys.
  Rorick MM, Pascual M Influenza evolution navigates stability valleys. [Journal Article]Elife 2013.:e00842.By reconstructing how an influenza protein collected in 1968 might have evolved into one collected in 2007, researchers have obtained new insights into the interactions between genetic mutations.
• Stability-mediated epistasis constrains the evolution of an influenza protein.
  Gong LI, Suchard MA, Bloom JD Stability-mediated epistasis constrains the evolution of an influenza protein. [Journal Article]Elife 2013.:e00631.JOHN MAYNARD SMITH COMPARED PROTEIN EVOLUTION TO THE GAME WHERE ONE WORD IS CONVERTED INTO ANOTHER A SINGLE LETTER AT A TIME, WITH THE CONSTRAINT THAT ALL INTERMEDIATES ARE WORDS: WORD→WORE→GORE→GONE→GENE. In this analogy, epistasis constrains evolution, with some mutations tolerated only after the occurrence of others. To test whether epistasis similarly constrains actual protein evolution, we created all intermediates along a 39-mutation evolutionary trajectory of influenza nucleoprotein, and also introduced each mutation individually into the parent. Several mutations were deleterious to the parent despite becoming fixed during evolution without negative impact. These mutations were destabilizing, and were preceded or accompanied by stabilizing mutations that alleviated their adverse effects. The constrained mutations occurred at sites enriched in T-cell epitopes, suggesting they promote viral immune escape. Our results paint a coherent portrait of epistasis during nucleoprotein evolution, with stabilizing mutations permitting otherwise inaccessible destabilizing mutations which are sometimes of adaptive value. DOI:http://dx.doi.org/10.7554/eLife.00631.001.
• Large-scale sequencing and the natural history of model human RNA viruses.
  Dugan VG, Saira K, Ghedin E Large-scale sequencing and the natural history of model human RNA viruses. [JOURNAL ARTICLE]Future Virol 2012 Jun 1; 7(6):563-573.RNA virus exploration within the field of medical virology has greatly benefited from technological developments in genomics, deepening our understanding of viral dynamics and emergence. Large-scale first-generation technology sequencing projects have expedited molecular epidemiology studies at an unprecedented scale for two pathogenic RNA viruses chosen as models: influenza A virus and dengue. Next-generation sequencing approaches are now leading to a more in-depth analysis of virus genetic diversity, which is greater for RNA than DNA viruses because of high replication rates and the absence of proofreading activity of the RNA-dependent RNA polymerase. In the field of virus discovery, technological advancements and metagenomic approaches are expanding the catalogs of novel viruses by facilitating our probing into the RNA virus world.
• Complete Genome Sequence of a Novel Reassortant H3N6 Avian Influenza Virus Isolated from Domestic Green-Winged Teal.
  Xiong C, Liu Q, Chen Q, et al. Complete Genome Sequence of a Novel Reassortant H3N6 Avian Influenza Virus Isolated from Domestic Green-Winged Teal. [Journal Article]Genome Announc 2013; 1(3)An avian influenza virus strain, A/domestic green-winged teal/Hunan/2036/2007(H3N6) (DGW-T2036), was isolated from healthy domestic green-winged teals (Anas crecca) in Hunan Province, South China. All eight gene segments of the isolate were sequenced. Genomic analysis demonstrated that this H3N6 virus is a novel reassortant avian influenza virus with a gene constellation originating from multiple ancestors.
• Full Genome Sequence of an Avian Influenza H5N1 Virus Isolated from the Environment in Hunan Province, China.
  Wang B, Zhang H, Chen Q, et al. Full Genome Sequence of an Avian Influenza H5N1 Virus Isolated from the Environment in Hunan Province, China. [Journal Article]Genome Announc 2013; 1(3)We isolated an avian influenza virus A/environment/Hunan/3/2011(H5N1) from a body of water in Hunan, China. The nucleotide sequence of the virus shares 95% homology with H5N1 from the east Asia region. Phylogenetic analysis indicates that its HA gene belongs to clade 2.3.2.1 and that other internal genes present different recombination features.
• Influenza: marketing vaccine by marketing disease.
  Doshi P Influenza: marketing vaccine by marketing disease. [Journal Article]BMJ 2013.:f3037.
• Does vaccine dose predict response to the monovalent pandemic H1N1 influenza a vaccine in children with acute lymphoblastic leukemia? A single-centre study.
  Leahy TR, Smith OP, Bacon CL, et al. Does vaccine dose predict response to the monovalent pandemic H1N1 influenza a vaccine in children with acute lymphoblastic leukemia? A single-centre study. [JOURNAL ARTICLE]Pediatr Blood Cancer 2013 May 16.BACKGROUND: Vaccination against influenza is an important strategy in preventing severe infection among children with acute lymphoblastic leukemia (ALL). Successful vaccination depends on both vaccine and host-related factors. We conducted a study on factors predicting the immunogenicity of the monovalent pandemic H1N1 (pH1N1) influenza A vaccine in children with ALL. METHODS: Children with ALL in our hospital were recruited and received two doses of the inactivated split-virion AS03-adjuvanted vaccine. The serological response was measured before each vaccine dose (Day 0 and 28) and 3 months after the second dose. Antibody titres were measured using a hemagglutination-inhibition assay. Seroconversion was defined as a ≥fourfold increase in antibody titre and a post-vaccination titre ≥1:40. RESULTS: Pre and post-vaccination titres were available from 45 children with ALL after one dose of the vaccine and 39 children after two doses. The seroconversion rate was 11.1% after one dose and 25.6% after the second dose. Univariate analysis demonstrated a significantly higher (P = 0.01) seroconversion rate among children who received the adult dose (0.5 ml) of the vaccine and a trend towards increased seroconversion (P = 0.07) by multivariate analysis. Factors including age, gender, lymphocyte count, treatment phase and regimen did not significantly affect the seroconversion rate. Children who received the adult dose demonstrated a significantly greater magnitude of serological response after both one dose (P = 0.04) and two doses (P = 0.001). CONCLUSIONS: These data suggest that the immunogenicity of the pH1N1 vaccine among children with ALL is improved by repeated and adult doses of the vaccine. Pediatr Blood Cancer 2013;9999:XX-XX. © 2013 Wiley Periodicals, Inc.
• Conserved epitopes dominate cross-CD8+ T-cell responses against influenza A H1N1 virus among Asian populations.
  Liu J, Wu B, Zhang S, et al. Conserved epitopes dominate cross-CD8+ T-cell responses against influenza A H1N1 virus among Asian populations. [JOURNAL ARTICLE]Eur J Immunol 2013 May 16.Novel strains of influenza A viruses (IAVs) have emerged with high infectivity and/or pathogenicity in recent years, causing worldwide concern. T cells are correlated with protection in humans through cross-reactive immunity against heterosubtypes of IAV. However, the different hierarchical roles of IAV-derived epitopes with distinct levels of polymorphism in the cross-reactive T-cell responses against IAV remain elusive. In this study, immunodominant epitopes scattered throughout the entire proteome of 2009 pH1N1 and seasonal IAVs were synthesized and divided into different pools depending on their conservation. The overall profile of the IAV-specific CD8(+) T-cell immunity was detected by utilizing these peptide pools and also individual peptides. A dominant role of the conserved peptide-specific T-cell immunity was illuminated within the anti-IAV responses, while the CD8(+) T-cell responses against the variable epitopes were lower than the conserved peptides. As previously demonstrated within a Caucasian population, we determined that GL9-specific T cells, which also utilize Vβ 17 TCR (BV19), play a pivotal role in IAV-specific T-cell immunity within an HLA-A2(+) Asian population. Our study objectively reveals the different predominant roles of T-cell epitopes among IAV-specific cross-reactive cellular immunity. This may guide the development of vaccines with cross-T-cell immunogenicity against heterosubtypes of IAV. This article is protected by copyright. All rights reserved.
• Survival of Respiratory Viruses on Fresh Produce.
  Yépiz-Gómez MS, Gerba CP, Bright KR Survival of Respiratory Viruses on Fresh Produce. [JOURNAL ARTICLE]Food Environ Virol 2013 May 17.In addition to enteric viruses of fecal origin, emerging zoonotic viruses such as respiratory coronaviruses and influenza viruses may potentially be transmitted via contaminated foods. The goal of this study was to determine the recovery efficiencies and the survival of two respiratory viruses, namely, adenovirus 2 (Ad2) and coronavirus 229E (CoV229E), on fresh produce in comparison to the enteric poliovirus 1 (PV1). Adenovirus was recovered with efficiencies of 56.5, 31.8, and 34.8 % from lettuce, strawberries, and raspberries, respectively. Coronavirus was recovered from lettuce with an efficiency of 19.6 % yet could not be recovered from strawberries. Poliovirus was recovered with efficiencies of 76.7 % from lettuce, but only 0.06 % from strawberries. For comparison purposes, the survival of Ad2, CoV229E, and PV1 was determined for periods up to 10 days on produce. The enteric PV1 survived better than both respiratory viruses on lettuce and strawberries, with only ≤1.03 log10 reductions after 10 days of storage at 4 °C compared to CoV229E not being recovered after 4 days on lettuce and reductions of 1.97 log10 and 2.38 log10 of Ad2 on lettuce and strawberries, respectively, after 10 days. Nevertheless, these respiratory viruses were able to survive for at least several days on produce. There is therefore the potential for transfer to the hands and subsequently to the mucosa via rubbing the eyes or nose. In addition, some respiratory coronaviruses (e.g., severe acute respiratory syndrome coronavirus) and adenoviruses are also capable of replication in the gut and there is thus some potential for acquisition through the consumption of contaminated produce.
• Immunologic Mechanism of Patchouli Alcohol Anti-H1N1 Influenza Virus May Through Regulation of the RLH Signal Pathway In Vitro.
  Wu XL, Ju DH, Chen J, et al. Immunologic Mechanism of Patchouli Alcohol Anti-H1N1 Influenza Virus May Through Regulation of the RLH Signal Pathway In Vitro. [JOURNAL ARTICLE]Curr Microbiol 2013 May 17.Patchouli alcohol (PA) is a kind of methanol extracted from traditional Chinese medicine Pogostemonis Herba. Our research aimed to observe the anti-influenza virus role of PA in vitro. 16HBE (human respiratory epithelial cell) was infected by H1N1 (A/FM1/1/47) to set the cell model. Then the 16HBE was co-cultivated with three kinds of immune cells: dendritic cells, macrophages, and monocytes, PA (the concentration is 10 μg/mL) was added as a treatment intervention for 24 h. The immune cells and the supernate were collected for RT-PCR and ELISA detection related to RLH (RIG-1-like helicases) pathway. Results showed that the IL-4 and IFN-γ in supernate were increased after H1N1 infection, and the PA treatment suppressed the expression of cytokines and the mRNA of RLH pathway. PA anti-influenza virus may through regulate the RLH singal pathway.