The XBB.1.5 subtype appears to be significantly more transmissible than other circulating omicron subtypes such as BQ.1.1. Omicron subtype XBB.1.5 has been detected in 46 countries to date. The majority of cases to date occur in the United States, where XBB.1.5 is the dominant variant nationwide, accounting for nearly 50%. In Europe, XBB.1.5 is still present at relatively low levels, and in Austria, XBB.1.5 was detectable at mostly very low levels in more than half of the wastewater treatment plants in early January 2023. The EU health authority ECDC currently classifies the risk associated with XBB.1.5 for incompletely or unvaccinated vulnerables as moderate to high. A serious change in the epidemiological situation is not assumed so far.
Further information on the new, emerging virus variant and current studies on various topics of Corona research is provided by the current GECKO report.
