Interferon antagonists encoded by emerging RNA viruses

Emerging viruses can be considered those which have recently appeared in the human population or which threaten to reemerge in the human population. This definition encompasses a variety of viruses including human specific pathogens such as human immunodeficiency virus (HIV) and hepatitis C virus (HCV), zoonotic viruses such as some arenaviruses or Nipah virus and arboviruses such as West Nile virus. This chapter will look at the mechanisms by which emerging viruses counteract the host IFNα/β system. Its focus will be on several examples of emerging RNA viruses, which are transmitted to humans via either an animal or arthropod host.