Coronaviruses impose health threats to humans and animals. Two β-coronaviruses, SARS-CoV and MERS-CoV, are highly pathogenic human pathogens. SARS-CoV cause the SARS epidemic in 2002-2003, with over 8000 infection and a fatality rate of∼10%. MERS-CoV emerged from the Middle East  in 2012. As of 16 October 2014, MERS-CoV had caused 877 infections with a fatality rate of ∼36%.