The first cases of a more infectious COVID-19 variant that was first recorded in South Africa have been detected in the United States. South Carolina officials announced Thursday that two people in the state—who have no history of international travel and live in different regions—have contracted the variant, which is especially dangerous because it spreads more quickly than other strains. There have also been reports that established COVID-19 vaccines may be slightly less effective at combating the B. 1.351 variant. The Centers for Disease Control and Prevention said the agency was still “early in its efforts to understand this variant and will continue to provide updates as we learn more. At this time, we have no evidence that infections by this variant cause more severe disease,” the CDC said in a statement shared with The Daily Beast.