Influenza A and B virions are packaged with their polymerases to catalyse RNA-dependent RNA polymerase activity. Since there is no evidence to rule in or out the permissiveness of influenza virions to triphosphate ribonucleotides, we functionally evaluated this. We found the means to stimulate influenza A and B RNA polymerase activity inside the virion, called natural endogenous RNA polymerase (NERP) activity. Stimulation of NERP activity increased up to 3 log10 viral RNA content, allowing the detection of influenza virus in otherwise undetectable clinical samples. NERP activation also improved our capacity to sequence misidentified regions of the influenza genome from clinical samples. By treating the samples with the ribavirin triphosphate we inhibited NERP activity, which confirms our hypothesis and highlights that this assay could be used to screen antiviral drugs. Altogether, our data show that NERP activity could be explored to increase molecular diagnostic sensitivity and/or to develop antiviral screening assays.


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  1. Influenza (seasonal) Fact Sheet N°211 [Internet] World Health Organization [online]; 2014
  2. Poehling KA, Edwards KM, Weinberg GA, Szilagyi P, Staat MA et al. The underrecognized burden of influenza in young children. N Engl J Med 2006; 355:31–40 [View Article][PubMed]
    [Google Scholar]
  3. CDC Influenza signs and symptoms and the role of laboratory diagnostics; 2015 Available from http://www.cdc.gov/flu/professionals/diagnosis/labrolesprocedures.htm
  4. CDC Rapid diagnostic testing for influenza: information for health care professionals; 2015 Available from http://www.cdc.gov/flu/professionals/diagnosis/rapidclin.htm#table2
  5. McHardy AC, Adams B. The role of genomics in tracking the evolution of influenza A virus. PLoS Pathog 2009; 5:e1000566 [View Article][PubMed]
    [Google Scholar]
  6. Holmes EC. RNA virus genomics: a world of possibilities. J Clin Invest 2009; 119:2488–2495 [View Article][PubMed]
    [Google Scholar]
  7. Aguiar RS, Costa LJ, Pereira HS, Brindeiro RM, Tanuri A. Development of a new methodology for screening of human immunodeficiency virus type 1 microbicides based on real-time PCR quantification. Antimicrob Agents Chemother 2007; 51:638–644 [View Article][PubMed]
    [Google Scholar]
  8. Das K, Aramini JM, Ma LC, Krug RM, Arnold E. Structures of influenza A proteins and insights into antiviral drug targets. Nat Struct Mol Biol 2010; 17:530–538 [View Article][PubMed]
    [Google Scholar]
  9. WHO, Network GIS Manual for the laboraroty diagnosis and virological surveillance of influenza; 2011 Available from http://apps.who.int/iris/bitstream/10665/44518/1/9789241548090_eng.pdf
  10. Szretter KJ, Balish AL, Katz JM. Influenza: propagation, quantification, and storage. Curr Protoc Microbiol 2006 Chapter 15:Unit 15G 1 [View Article][PubMed]
    [Google Scholar]
  11. Mesquita M, Fintelman-Rodrigues N, Sacramento CQ, Abrantes JL, Costa E et al. HIV-1 and its gp120 inhibits the influenza A(H1N1)pdm09 life cycle in an IFITM3-dependent fashion. PLoS One 2014; 9:e101056 [View Article][PubMed]
    [Google Scholar]
  12. Baillie GJ, Galiano M, Agapow PM, Myers R, Chiam R et al. Evolutionary dynamics of local pandemic H1N1/2009 influenza virus lineages revealed by whole-genome analysis. J Virol 2012; 86:11–18 [View Article][PubMed]
    [Google Scholar]
  13. Souza TM, Resende PC, Fintelman-Rodrigues N, Gregianini TS, Ikuta N et al. Detection of oseltamivir-resistant pandemic influenza A(H1N1)pdm2009 in Brazil: can community transmission be ruled out?. PLoS One 2013; 8:e80081 [View Article][PubMed]
    [Google Scholar]
  14. Sacramento CQ, Fintelman-Rodrigues N, Marttorelli A, de Freitas CS, de Melo GR et al. The ribavirin analog methyl 1-benzyl-1H-1,2,3-triazole-4-carboxylate inhibits influenza in vitro and in vivo replication. Accompanying manuscript. Journal of General Virology 2017
    [Google Scholar]
  15. WHO WHO recommendations on the use of rapid testing for influenza diagnosis; 2005 Available from http://www.who.int/influenza/resources/documents/RapidTestInfluenza_WebVersion.pdf
  16. Binsaeed AA, Al-Khedhairy AA, Mandil AM, Shaikh SA, Qureshi R et al. A validation study comparing the sensitivity and specificity of the new DrKSU H1N1 RT-PCR kit with real-time RT-PCR for diagnosing influenza A (H1N1). Ann Saudi Med 2011; 31:351–355 [View Article][PubMed]
    [Google Scholar]
  17. Mello W. The role of laboratory diagnosis of influenza. Revista Pan-Amazônica de Saúde 2010; 1:191–193
    [Google Scholar]
  18. WHO Manual for the laboratory diagnosis and virological surveillance of influenza; 2011

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