This recommendation was generated by the Centers for Disease Control when the first cases of COVID-19 as being a new/novel virus were discovered in the US.  Hence the name COVID –19.  It was already identified in travelers who had come from Wuhan, China and returned to California and Arizona.  They predicted person to person spread but at the time may not have known how easily it was transferred.  Nevertheless, “Do the FIVE” was put out immediately and still holds.

Do the Five!