The cost and challenge of vaccine development for emerging and emergent infectious diseases.

Abstract

Over the past two decades, new infectious threats have emerged almost yearly.1 Outbreaks of Ebola virus disease, severe acute respiratory syndrome, Middle East respiratory syndrome, and Zika virus disease were interspersed between epidemics of H5N1 and H7N9 avian, swine, and H1N1 influenza. While most developed countries focused on these, disease due to Lassa, Nipah, and Crimean-Congo haemorrhagic fever viruses continued unabated. Other emergent pathogens such as severe fever and thrombocytopenia syndrome virus, and Powassan virus remain restricted in scope.