Emerging Infectious Diseases

Emerging and re-emerging infectious diseases pose a constant and present threat to global health and economy. Even excluding obvious threats such as HIV and pandemic flu, the last two decades have seen world-changing episodes like the spread of the West Nile Virus across North America, and the 2003 SARS pandemic. Estimates put the global macro-economic impact of SARS at US$30-$100 billion. Emerging zoonoses are a particular concern when human and environmental factors force the unintended overlap of otherwise naive ecological niches, which increase the chances for viruses to jump host species and to generate “spillover events” in non-natural animal or human hosts.

In most cases, zoonotic viruses, being ill adapted to the new animal or human host, are highly pathogenic, and infections lead to rapid, severe disease with high fatality. Ebola and Marburg viruses (filioviruses), and Hendra and Nipah viruses (henipaviruses) are the most lethal examples of recent zoonoses. An overview of our lab’s research on henipaviruses is provided here. For a more detailed introduction, please refer to Henipavirus: Ecology, Molecular Biology and Pathogenesis (Benhur Lee and Paul Rota, Editors, Current Topics in Microbiology and Immunology.2012, Vol 358.)

In addition, arenaviruses, hantaviruses, dengue and chikungunya viruses may even be considered as diseases of global warming as climate change increases the geographical range of their animal or arthropod hosts. Given the increasing number of viral zoonoses, the traditional “one bug-one drug” paradigm is clearly inadequate as a model for antiviral drug development. A past focus in our lab was developing broad-spectrum antiviral strategies that target either viral or host cell components that are essential for entry of multiple classes of virus. We are currently pivoting to structurally informed antibody engineering strategies to develop broadly neutralizing antibodies against the ever increasing spectrum of divergent henipaviruses and exotic paramyxoviruses found across the world.

Understanding the mechanisms of spread, the nature of persistence of these viruses in their animal hosts, and their pathogenesis in humans, is critical for the development of any counteracting antiviral strategies and vaccines, and underscores the importance of multidisciplinary approaches for studying viral Emerging Infectious Diseases.