One case of a new version of the Omicron coronavirus variant (BA.4) has been reported in Belgium, announced virologist Marc Van Ranst.
While there is no cause for alarm, the World Health Organisation (WHO) has called for close monitoring of the BA.4 and BA.5 Omicron sub-variants, which were discovered in South Africa.
“So far, one BA.4 infection has been found in Belgium,” Van Ranst said, after Tulio de Oliveira of the Centre for Epidemic Response and Innovation (CERI) in South Africa stated that the sub-variants had already been detected in Botswana, Germany, Denmark, and the UK.
WHO vraagt om BA.4 en BA.5 subvarianten van Omikron nauwgezet op te volgen. Deze subvarianten werden ontdekt in Z-Afrika, en komen nu ook sporadisch in andere landen voor. In België werd tot nu toe één BA.4 teruggevonden.
— Marc Van Ranst (@vanranstmarc) April 11, 2022
The Belgian BA.4 case was detected in the French-speaking part of Belgium and discovered by the ULB university in Brussels (Université Libre de Bruxelles) last week.
Whether this version is more or less pathogenic than the BA.2 version, which currently accounts for the vast majority (95,7%) of coronavirus infections in Belgium, is too early to say.
“It is normal for viruses to mutate and generate sub-variants,” Van Ranst said. “At present, there is no reason to believe that BA.4 or BA.5 behave differently from BA.1 or BA.2 clinically or in terms of vaccine protection.”