The World Health Organization on Friday classified the B.1.1.529 variant detected inSouth Africa as a SARS-CoV-2 "variant of concern," saying it mayspread more quickly than other forms.
Preliminary evidence suggested there is an increased risk ofreinfection and there had been a "detrimental change in COVID-19epidemiology," it said in a statement after a closed meeting ofindependent experts who reviewed the data.
Infections in South Africa had risen steeply in recentweeks, coinciding with detection of the variant now designatedas omicron, WHO said.
"This variant has a large number of mutations, some of whichare concerning. Preliminary evidence suggests an increased riskof reinfection with this variant, as compared to other (variantsof concern), it said.
Omicron is the fifth variant to carry such a designation.
"This variant has been detected at faster rates thanprevious surges in infection, suggesting that this variant mayhave a growth advantage," the WHO said.
Current PCR tests continue to successfully detect thevariant, it said.
Earlier, the WHO cautioned countries against hastilyimposing travel restrictions linked to the variant of COVID-19,saying they should take a "risk-based and scientific approach." Global authorities reacted with alarm to the new variantdetected in South Africa, with the EU and Britain among thosetightening border controls as scientists sought to find out ifthe mutation was vaccine-resistant.
"At this point, implementing travel measures is beingcautioned against," WHO spokesman Christian Lindmeier told aUN briefing in Geneva. "The WHO recommends that countriescontinue to apply a risk-based and scientific approach whenimplementing travel measures."
It would take several weeks to determine the variant'stransmissibility and the effectiveness of vaccines andtherapeutics against it, he said, noting that 100 sequences ofthe variant have been reported so far.
People should continue to wear masks whenever possible,avoid large gatherings, ventilate rooms and maintain handhygiene, Lindmeier added.
Mike Ryan, WHO's emergency director, praised South Africanpublic health institutions for picking up the signal of the newvariant.
But he warned that while some countries had systems in placeto do this, the situation elsewhere was often unclear."So it's really important that there are no knee-jerkresponses here. Especially with relation to South Africa," hesaid. "Because we've seen in the past, the minute that there isany mention of any kind of variation, then everyone is closingborders and restricting travel."