4 ms·There are 4 of them actually. HCoV-OC43, HCoV-HKU1, HCoV-NL63 and HCoV-229E.by im3w1l 7y agoThere are 4 of them actually. HCoV-OC43, HCoV-HKU1, HCoV-NL63 and HCoV-229E.