In the space of just six weeks, a new coronavirus, from a family that historically was not viewed as a global health concern, has become daily headline news around the globe. The 21st century marked its arrival with the emergence of three previously unknown coronaviruses. SARS-CoV (severe acute respiratory syndrome coronavirus) was recognized in November 2002 [1, 2], MERS-CoV (Middle East respiratory syndrome coronavirus) in June 2012 [3, 4], and 2019-nCoV in December 2019 [5]. Previously, human coronaviruses, known since the 1960s, were viewed as being only marginally relevant to the clinic, except for infants, the elderly, and immunocompromised individuals [1, 6, 7].
The 2019 coronavirus: Learning curves, lessons, and the weakest link