SINGAPORE, 17 DECEMBER 2018 – Scientists from A*STAR’s Bioinformatics Institute (BII), together with collaborators in Amsterdam, have discovered that the evolution of influenza viruses from natural selection is more closely linked to the transmission stage rather than within the human body. Their findings have been published in the peer-reviewed journal Nature Ecology and Evolution on 3 December 2018.

Influenza viruses are able to cause seasonal outbreaks year after year as a flu virus can evolve to escape the immunity that we generate to prior infections and vaccinations. Traditionally, it has been thought that micro-evolution of influenza viruses (also termed as “antigenic changes”) is the result of a flu virus navigating the immune systems of individuals with varying infection histories, with natural selection compelling the flu viruses to undergo small genetic changes as they replicate, and rendering our bodies’ immune systems unable to recognise the evolved viruses.

What the A*STAR scientists discovered in their study was markedly different. They found that these small changes in a flu virus were not generated within an individual because of individual immunity, but more likely attributed to transmissions between individuals instead, with population immunity being the key driver for such changes. This means that public health measures and interventions targeting transmissions of influenza viruses are crucial not only to limit viral spread, but also to limit the antigenic evolution of the viruses. If antigenic change can be reduced or delayed, this could in turn result in higher efficacy of flu vaccines over longer periods of time before they need to be changed, bringing greater healthcare and economic benefits.

The A*STAR-led study was a fully computational one, with the scientists analysing the genetic sequences of more than 25,000 influenza viruses collected between 2009 and 2016 from WHO routine surveillance efforts that were stored on publicly available global databases via the Global Initiative for Sharing All Influenza Data (GISAID).

“Our work questions the conventional assumption that antigenic changes in an influenza virus are generated within an infected patient due to the patient’s previous infections or vaccinations,” said A*STAR scholar Alvin Han, the lead author of the study.

“Influenza vaccines remain as some of the best protective tools currently available to limit human influenza virus infections, and can be used to break transmission chains. Our work also highlights the need for further studies on how overall population immunity shapes the genetic changes in influenza viruses,” added Dr Sebastian Maurer-Stroh, Senior Principal Investigator at A*STAR’s Bioinformatics Institute.

Link to paper in Nature Ecology & Evolution:




Notes to Editor:

The research findings described in this news alert can be found in the scientific journal Nature Ecology & Evolution, under the title “Individual immune selection pressure has limited impact on seasonal influenza virus evolution” by Alvin X. Han1, Sebastian Maurer-Stroh2, Colin A. Russell3.

  1. Bioinformatics Institute, Agency for Science, Technology and Research (A*STAR), Singapore
  2. Bioinformatics Institute, Agency for Science, Technology and Research (A*STAR), Singapore
  3. Laboratory of Applied Evolutionary Biology, Department of Medical Microbiology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands

Corresponding author: Colin A. Russell.

Information in “Notes to Editor” correct as of online publishing date, 3 Dec 2018.

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About the Bioinformatics Institute (BII)

The Bioinformatics Institute (BII) is an institute of the Agency for Science, Technology and Research (A*STAR) set up in July 2001. With a multi-disciplinary focus and collaborative outlook, BII recognises the need for depth and breadth in all its activities for building a thriving world-class biomedical research, graduate training and development hub in Singapore. In addition, BII is proactively involved in building a national resource centre in bioinformatics to meet the evolving needs of the scientific community in Singapore. The spectrum of research activities in BII includes theoretical approaches aimed at understanding biomolecular mechanisms that underlie biological phenomena, the development of computational methods to support this discovery process, and experimental verification of predicted molecular and cellular functions of genes and proteins with biochemical methods. BII also has a division of translational research aimed at enhancing applied research and industry collaborations.

For more information on BII, please visit:

About the Agency for Science, Technology and Research (A*STAR)

The Agency for Science, Technology and Research (A*STAR) is Singapore's lead public sector agency that spearheads economic oriented research to advance scientific discovery and develop innovative technology. Through open innovation, we collaborate with our partners in both the public and private sectors to benefit society.

As a Science and Technology Organisation, A*STAR bridges the gap between academia and industry. Our research creates economic growth and jobs for Singapore, and enhances lives by contributing to societal benefits such as improving outcomes in healthcare, urban living, and sustainability. 

We play a key role in nurturing and developing a diversity of talent and leaders in our Agency and research entities, the wider research community and industry. A*STAR’s R&D activities span biomedical sciences and physical sciences and engineering, with research entities primarily located in Biopolis and Fusionopolis. For ongoing news, visit

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