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.

Tampa Mayor Jane Castor signed an executive order Thursday requiring the use of face coverings at outdoor Super Bowl-related activities to help mitigate the spread of COVID-19 in the Florida city.

The order targets sites where large crowds of people are likely to congregate around the Super Bowl this weekend, with limited ability to remain socially distant from each other. They include "Event Zones" in areas of downtown Tampa and surrounding Raymond James Stadium, as well as "Entertainment Districts," including Ybor City Historic District, the South Howard Commercial Overlay District, the Central Business District and the Channel District.

Those exempt from the order include children under the age of 5, someone communicating with a hearing-impaired individual and people with existing health conditions who would be impaired by a mask.

The Super Bowl will be held on Feb. 7 between the Kansas City Chiefs and hometown Tampa Bay Buccaneers. The mask mandate is in effect now through Feb. 13. Those who violate it could be subject to a $500 fine.

The NFL had previously announced that masks will be required in the stadium unless eating or drinking.

Under a previous order still in effect, masks are required in Tampa at indoor locations outside the home when social distancing cannot be maintained.

ABC News' Will McDuffie contributed to this report