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.

There have been more COVID-19 cases reported globally in the past two weeks than during the first six months of the pandemic, according to the World Health Organization.

Almost exactly a year ago, there were fewer than 100 confirmed cases of the virus outside of China, WHO Director-General Dr. Tedros Adhanom Ghebreyesus noted during a media briefing Friday. This week, the number of reported cases globally surpassed 100 million.

"Now, vaccines are giving us another window of opportunity to bring the pandemic under control. We must not squander it," Tedros said.

At the same time, Tedros warned that vaccine hoarding will be a "catastrophic moral failing" that will ultimately "keep the pandemic burning" and hinder economic recovery.

His comments come after the European Union publicly fought with AstraZeneca this week over how many doses it can expect of the drugmaker's COVID-19 vaccine. After regulators approved the vaccine Friday, the EU enacted an export restriction on doses produced in the bloc. WHO officials called the move "concerning" and part of a "worrying trend."

"Vaccine nationalism might serve short-term political goals, but it's ultimately short-sighted and self-defeating. We will not end the pandemic anywhere until we end it everywhere," Tedros said. "My message to governments is to vaccinate your health workers and older people, and share excess doses with COVAX, so other countries can do the same."

ABC News' Kirit Radia contributed to this report.