Early data indicates the Omicron Covid variant may more easily reinfect people who have already had the virus or been vaccinated than previous variants, but could also cause milder disease, the World Health Organization said Thursday.
“Emerging data from South Africa suggests increased risk of reinfection with Omicron,” WHO chief Tedros Adhanom Ghebreyesus told reporters, adding that “there is also some evidence that Omicron causes milder disease than Delta”.
But he stressed that more data was needed before drawing firm conclusions, and urged countries everywhere to boost their surveillance to help provide a clearer picture of how Omicron is behaving.
The hopeful assessments came as global concern grew over the heavily mutated variant, which has forced dozens of nations to re-impose border restrictions and raised the possibility of a return to economically punishing lockdowns.
Even if it does turn out that Omicron causes less severe disease, Tedros warned against slacking off vigilance against the virus.
“Any complacency now will cost lives,” he warned.
WHO emergencies director Michael Ryan agreed, pointing out that so far the data indicates the variant is “efficiently transmitting, and probably more efficiently transmitting even than the Delta variant.”
“That does not mean that the virus is unstoppable,” he said.
“But it means the virus is more effi