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Surveillance of Human Influenza in Indonesia, October 2008-March 2010

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  • Surveillance of Human Influenza in Indonesia, October 2008-March 2010

    If you go to Bird Flu Information Corner, you can click the graphs/pictures to enlarge them.

    Surveillance of Human Influenza in Indonesia, October 2008-March 2010

    Posted by Ida on June 29, 2011

    Influenza A viruses cause epidemics and pandemics. Pandemic viruses emerge when viruses that have acquired new HA genes, by genetic reassortment or interspecies adaptation, are introduced to humans. Reassortment occurs in a host infected with more than one influenza virus, as occurred with the 1957 Asian H2N2, the 1968 Hong Kong H3N2, and pandemic (H1N1) 2009 viruses.


    Surabaya, East Java: Location of the surveillance

    Avian H5N1 influenza viruses have caused outbreaks in animals and infections humans since 1997. Human influenza viruses, including Hong Kong H3N2, pandemic (H1N1) 2009, influenza B, and to a very limited extent Russian H1N1 viruses, are epidemic worldwide. Reassortment between avian H5N1 and human H3N2 viruses creates hybrid viruses with substantial virulence, while pandemic (H1N1) 2009 viruses reassort even more readily with H5N1 viruses, posing a threat to public health.

    It is essential to monitor epidemics of seasonal and pandemic (H1N1) 2009 human viruses, particularly in countries where H5N1 virus prevalence is high like Indonesia. Therefore, the collaboration work between Kobe University and Institute of Tropical Disease, Airlangga University conducted surveillance in Surabaya, East Java from October 2008 to March 2010.

    During the period of surveillence, we collected throat swab samples of patients with flu-like symptoms from 3 hospitals, and then grew the virus on cell culture. Fluids of cells which showing specific viral damage, or cytopathic effect, were collected and rapid tested for influenza A and B, and the genes were amplified and directly sequenced.


    Fig 1. Yamaoka et al. (2011). Isolation of human influenza virus during the rainy season in Surabaya


    We found that seasonal influenza peaked during the rainy season of Surabaya (from November to May), consistent with previous surveillance studies mainly in Java from 1999-2003. Pandemic (H1N1) 2009 virus was first isolated in our study in July 2009, one month after the first outbreak of this virus in Indonesia (Fig 1. Yamaoka et al.).


    Fig 2. Yamaoka et al. Demographics of seasonal influenza and pandemic (H1N1) 2009 patients
    These characteristics of pandemic (H1N1) 2009 virus infection, that is, younger patients with milder symptoms, have been reported by
    others, indicating that the pandemic (H1N1) 2009 virus in Indonesia at this time was similar to that in other countries (Fig 2. Yamaoka et al.)

    The phylogenetic analyses of HA either pandemic H1N1 and H3N2 show that Indonesia isolates are located in the same group of recent isolates (indicated by mutation S220T). Sequences are available here (Genbank accession numbers will come later)


    HA H3N2 phylogenetic tree



    HA H1N1 phylogenetic tree


    Yamaoka, M., Palilingan, J. F., Wibisono, J., Yudhawati, R., Nidom, R. V., Alamudi, M. Y., Ginting, T. E., Makino, A., Nidom, C. A., Shinya, K. and Kawaoka, Y. (2011), Virological surveillance of human influenza in Indonesia, October 2008-March 2010. Microbiology and Immunology, 55: 514–517. doi: 10.1111/j.1348-0421.2011.00344.x



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