Los Angeles County on Saturday surpassed 1 million coronavirus cases since reporting its first infection nearly a year before and also recorded its first instance of a new, more contagious variant of the virus that was initially identified in the United Kingdom.

The variant, B.1.1.7, had previously been found in California’s San Diego and San Bernardino counties, as well as 14 other U.S. states, according to the Centers for Disease Control and Prevention. It is not believed to make people sicker or increase their risk of death but appears to spread more easily, raising fears it could hamper efforts to bring the pandemic under control if it displaces other strains and becomes dominant in the region.

Officials believe the variant has been present in L.A. County for some time and is already spreading in the community. The person found to have contracted it is a man who recently spent time in L.A. County but has since traveled to Oregon, where he is currently isolated, officials said. Quest Laboratories in Washington confirmed the discovery, officials said.

Health experts have been worried for some time that the new strain will bring even more challenges to a region that has become an epicenter of COVID-19 in America, pushing hospitals to the brink and infecting an estimated 1 in 3 county residents since the beginning of the pandemic.

Officials hope that rapid vaccination be a weapon against the new strain, which a Centers for Disease Control and Prevention report released Friday said will show “rapid growth in early 2021, becoming the predominant variant in March.”