The Omicron variant of Covid-19 continues to pose a “very high risk” to healthcare systems across countries, the World Health Organization said on Tuesday.

In its weekly epidemiological update on Covid-19, the global health body also warned that the Omicron variant was likely to spread faster than the Delta strain.

“Consistent evidence shows that the Omicron variant has a growth advantage over the Delta variant with a doubling time of two to three days, and rapid increases in the incidence of cases is seen in a number of countries, including those where the variant has become the dominant SARS-CoV-2 variant...” the WHO said.

However, the global health body noted that daily Covid-19 cases have been declining in South Africa, where the Omicron variant was first detected. Citing early data from the United Kingdom, South Africa and Denmark, the health body also said that the risk of hospitalisation among patients infected by the Omicron variant was lower than the those who contracted Delta.

However, the WHO cautioned that more data was needed to draw conclusions on the requirement of oxygen and ventilators in Omicron cases, as also on the difference in the severity of the disease between vaccinated and unvaccinated people.

Global Covid-19 cases increased by 11% between December 20 and 26 as compared to the previous week. The number of deaths, however, remained similar.

Among the WHO’s six regions, the Americas registered the highest weekly increase in coronavirus cases (39%), followed by the African Region (7%).