Commentary
COVID-19 is only one form of coronavirus. Other common human coronaviruses include types 229E, NL63, OC43, and HKU1. These usually cause mild to moderate upper-respiratory tract illnesses, like the common cold.

COVID-19 is only one form of coronavirus. Other common human coronaviruses include types 229E, NL63, OC43, and HKU1. These usually cause mild to moderate upper-respiratory tract illnesses, like the common cold.