World Health Organization officials held a news briefing Monday to discuss mutations in the coronavirus responsible for new strains in both South Africa and the U.K.
WHO Director-General Tedros Adhanom Ghebreyesus said the new strain of the virus spreading in the U.K. is reported to be more infectious, but there's no evidence it is more deadly. He said that containing transmission of the coronavirus is key — the more opportunity the virus has to spread, the more opportunity it has to mutate.
The new strain of the virus in the U.K. prompted dozens of countries in the European Union and around the world to close their borders to travelers from the country, and for U.K. officials to tighten stay-at-home restrictions.
Epidemiologist Maria Van Kerkhove, the WHO's technical lead for coronavirus, said U.K. researchers are looking at transmission rates for the new strain and have seen an increase. Researchers are also investigating whether the variant leads to more severe cases of COVID-19 or more deaths, and so far have not seen any indication it does, she said, as well as researching antibody response to the new strain.
While the coronavirus is nowhere near as infectious as the mumps or measles viruses, someone with the new U.K. strain could infect an average of 1.5 other people, rather than the 1.1 average for the earlier strain of the coronavirus. That means the virus could spread faster. British officials told the WHO that it may have been circulating as early as September.
Dr. Mike Ryan, the executive director of WHO's Health Emergencies Program, said that there is no evidence that the variant "will change the value of vaccines going forward," but in response to a question from CBS News' Pamela Falk at the press conference, Ryan said, "This is being tested, but first of all, you don't know when you start."
The new variant found in South Africa contains a similar mutation to the U.K. strain, Van Kerkhove said, but is a separate variant.
Cases of COVID-19 are surging in the U.K., which curtailed the expected relaxation of safety measures for Christmas. More than 67,700 people in that country have died from the virus, according to data compiled by Johns Hopkins University. In South Africa, 24,691 have died.
Nearly 77 million people around the world have been diagnosed with COVID-19 since the beginning of the pandemic, and almost 1.7 million have died.