An adult in South Carolina’s Lowcountry region has become the state’s first confirmed case of the United Kingdom COVID-19 variant, South Carolina’s Department of Health and Environmental Control said.

The person "has an international travel history," the department said.

The U.S. has confirmed at least 434 cases of the B.1.1.7 U.K. variant across 30 states, South Carolina officials said.

"Experts agree that existing vaccines work to protect us from this variant, even if we don’t know just how effective they are," the South Carolina officials said. "At this time, there’s no conclusive evidence to prove that the B.1.1.7 variant causes more severe illness."

ABC News’ Josh Hoyos contributed to this report.

The Coachella Valley Music and Arts and Stagecoach Country Music festivals, set for April, were canceled on Friday by Dr. Cameron Kaiser, health officer for Riverside County, California.

Riverside County’s positivity rate stands at 20%. The county has 0% bed availability in its intensive care units.

January has been the deadliest month since the pandemic began, with 90,844 total deaths, according to data compiled by Johns Hopkins University.

The U.S. coronavirus death toll stands at 436,810 -- with the Center for Disease Control and Prevention projecting that more than 77,000 deaths could be reported by Feb. 20.

California is now the second U.S. state with known detection of the Brazil P.1 variant.

Minnesota health officials confirmed earlier this week the nation's first known COVID-19 case associated with the variant.

Inside Stanford's Clinical Virology Laboratory, Dr. Benjamin Pinsky and his team found two strains of the virus: the Brazil strain and the U.K. strain, KGO reported Saturday morning.

"It's in about 17% of the samples that we've sequenced," Pinsky told KGO.

Dave McGillivray, the race director of the Boston Marathon, has been selected by the state of Massachusetts to run the mass vaccination operations at Gillette Stadium and Fenway Park.

McGillivray owns DMSE Sports, which organizes and manages dozens of outdoor events every year. To help keep DMSE Sports afloat, McGillivray connected with CIC Health -- which operates the mass COVID-19 vaccination sites at Fenway Park and Gillette Stadium -- through the state of Massachusetts.

Now, McGillivray is running logistics for both sites.

"For me, the feeling is so good that the thing that knocked us to our knees is now the thing that is allowing us to do good: that we're keeping people healthy, we're saving lives and we're even bringing our own industry back," McGillivray said in an interview with Boston ABC affiliate WCVB().

Fenway Park is the home of the Boston Red Sox, while Gillette Stadium, located in Foxborough, is the home stadium for the New England Patriots. The Gillette Stadium site opened two weeks ago, with Fenway officially opening Monday. Both sites are expected to administer 5,000 doses per day once fully up and running.

The Boston Marathon, usually held in April, has been postponed to October. The in-person event was canceled in 2020, though it was held virtually.

ABC News' Arielle Mitropoulos contributed to this report.