European countries are experiencing a surge in Covid-19 hospitalisations driven by sub-variants of the highly infectious Omicron strain, threatening a fresh global wave of the disease as immunity levels wane and pandemic restrictions are lifted.
Admissions have risen in several countries including France and England, according to data analyzed by the Financial Times. The BA.5 sub-variant of
Omicron now accounts for more than 80 percent of new infections in Portugal. In Germany, where admissions have been rising for over a week, the share of Covid infections ascribed to BA.5 doubled at the end of last month.
Experts warn that the widespread scaling back of testing and surveillance may be compromising the ability of countries to spot new mutations and react quickly. They fear this could lead to waves later in the year that will put pressure on health systems and potentially prove harder to contain.
“We’re not out of the woods with this at all. The biggest concern is we’ve let our guard down quite considerably,” said Lawrence Young, a virologist at the UK’s University of Warwick. A key question concerns how the situation may develop in the northern hemisphere when it enters its winter months, he said, as health systems contend with seasonal respiratory viruses on top of the likely arrival of new variants.
Piotr Kramarz, head of surveillance at the European Centre for Disease
Prevention and Control, said Omicron sub-variants such as BA.4 and BA.5 had an element of “immune escape” — meaning that neither previous infections nor vaccines provide such strong protection — which was driving them to overtake previously dominant variants.
Kramarz said BA.4 and BA.5 did not appear to lead to a more severe illness, but he warned that those who had already had the virus were being infected again. Triple-jabbed people were also falling sick, although evidence suggested that vaccines continued to provide strong protection against the worst outcomes.