South Carolina reports first-known U.S. cases of South African COVID variant

South Carolina health officials have reported the first-known U.S. COVID-19 cases of a fast-spreading variant discovered in South Africa, the Centers for Disease Control and Prevention announced on Thursday.

Why it matters: Though the CDC has "no evidence that infections by this variant cause more severe disease," preliminary data indicates it may spread faster and more easily than other variants.

What they're saying: "CDC’s recommendations for slowing the spread — wearing masks, staying at least 6 feet apart from others, avoiding crowds, ventilating indoor spaces, and washing hands often — will also prevent the spread of this variant," the agency said.

Driving the news: Vaccine developer Novavax announced the results of the phase 3 United Kingdom trial for its coronavirus vaccine on Wednesday, and the company showed that its shot was 60% effective against the South African variant.

• Novavax reported that the vaccine was 85.6% effective against the variant strain first discovered in the U.K., and 95.6% effective against the original coronavirus strain.

The big picture: Moderna, Pfizer and now Novavax have each reported that their vaccines, while still effective, offer less protection against the South African variant.

• On Monday, Minnesota reported America's first-known case of a Brazilian variant of the coronavirus, which also seems to spread more rapidly than the original disease.
• Multiple states reported their first cases of the U.K. variant in late December 2020.

Go deeper: Coronavirus variants demand a tougher response