FAIRFIELD-SUISUN, CALIFORNIA Coronavirus patients coming in emergency are housed in a makeshift ER unit established in a tent at Arrowhead Regional Medical Center on Dec. 23 in Colton, California. (Irfan Khan/Los Angeles Times/TNS) Could a homegrown coronavirus strain be partly to blame for California’s surge? California scientists have discovered a homegrown coronavirus strain that appears to be propagating faster than any other variant on the loose in the Golden State. Two independent research groups said they stumbled upon the new strain while looking for signs that a highly transmissible variant from the United Kingdom had established itself here. Instead, they found a new branch of the virus’ family tree – one whose sudden rise and distinctive mutations have made it a prime suspect in California’s vicious holiday surge.