The World Health Organization (WHO) on Friday cautioned countries against immediately imposing travel restrictions in response to news of a new COVID-19 variant, saying there must be a “risk-based and scientific approach.“The warning, reported by Reuters, came as WHO officials met to discuss the new B.1.1.529 variant.Want more airline-specific news? Sign up for TPG’s free new biweekly Aviation newsletter!About 100 instances of the new variant were discovered in South Africa this week, Gauteng province. Four cases were found in foreigners visiting Botswana, while one case each has been reported in Israel and Hong Kong, both in travelers returning from southern Africa.The U.K. on Thursday banned flights from South Africa and five nearby African countries, including Namibia, Botswana, Zimbabwe, Lesotho and Eswatini. Flights will resume after Sunday, but entry will be restricted to legal residents who will have to quarantine.The European Union said it was looking to similarly restrict travel, while Italy, Germany, France, the Netherlands, Malta and Croatia imposed their own restrictions. Israel banned its citizens from traveling to South Africa, Bahrain said it would ban some travelers, and India, Singapore and Japan said they would enhance restrictions.Sign up for our daily newsletterEmail addressSign upI would like to subscribe to The Points Guy newsletters and special email promotions. The Points Guy will not share or sell your email. See privacy policy.The new variant has caused significant concern among scientists and health officials because it has more than 30 mutations of the spike protein that it uses to invade human cells — about twice the number of the delta variant — which could possibly render vaccines less effective against it. The new variant differs dramatically from the original strain of the virus, which served as the basis for the current vaccines.Scientists have also cautioned that much is still unknown about the mutations, including the degree to which the variant is more contagious or able to neutralize antibodies, if at all. It is expected to take several weeks for researchers to gather more definitive information.On Friday, Dr. Anthony Fauci, the top infectious diseases official at the National Institutes for Health (NIH), said that U.S. health officials were in talks with their South African counterparts.In an interview with CNN, Fauci suggested that the U.S. does not intend to impose travel restrictions imminently.“You don’t want to say you are going to do it until you have scientific reason to do it.”