In a report released with an epidemiological update as of 20 January, the European Centre for Disease Prevention and Control (ECDC) notes that Omicron "has been identified in all countries" of the European Union and European Economic Area, with an "estimated prevalence of 69.4 percent", up 20 perceent from the previous week.
"Through studies conducted in various settings, the risk of hospitalisation was found to be lower for Omicron than for the Delta variant. However, prior immunity to natural infection, vaccination including booster doses and improved treatment options contribute to less severe outcomes, making it difficult to estimate the inherent risk of severe infection," contextualises the European agency.
Even so, "most studies have found a reduction in risk in the range of 50-60 percent", specifies the ECDC.
Data advanced by the European centre show that of the total 155,150 cases of the Omicron variant reported between 20 December 2021 and 9 January 2022, 1.14 percent of these resulted in hospitalisations, 0.16 percent required respiratory support in intensive care units and 0.06 percent died.
In this period, there were 570 cases of this strain in Portugal reported to the ECDC, according to the report.
"Early studies suggest that current vaccines may be less effective against Omicron infection, although they still provide protection against hospitalisation and serious illness. Given the exponential growth advantage of the spread and the high number of cases, any potential benefits of lower observed severity may be outweighed by the sheer number of severe outcomes over time," the ECDC warns.
The European agency therefore speaks of an overall level of very high public health risk associated with the emergence and spread of Omicron.
"Member States should urgently assess their acceptable levels of residual risks, current health system capacities and available risk management options, for example by adopting contingency measures," the ECDC adds.
The position comes at a time of high resurgence of cases of infection with the SARS-CoV-2 coronavirus, which does not yet translate into high rates of hospitalisation or death.
Contributing to the high number of cases, which are reaching record highs, is the high transmissibility of the Omicron variant of SARS-CoV-2.
The ECDC, portraying new cases of Omicron infection, specifies that the average age is 20 to 33 years and that transmission occurs mainly locally, with only 7 percent of cases being imported or travel-related.