The EU disease agency said Omicron subvariant XBB.1.5 could become the dominant strain in Europe within months. The subtype now accounts for a quarter of US Covid cases, while the European Center for Disease Prevention and Control (ECDC) said mathematical modeling suggested the subtype could “become the dominant form in the EU after one to two months, Given the current low ratio in the EU/EEA and its expected growth rate”.
The subtype is considered the most transmissible to date. The health body said the risk associated with the subtype was estimated to be low. However, “the risk is moderately higher for vulnerable individuals such as the elderly and the unvaccinated and immunocompromised”.
The agency also said there were “several knowledge gaps” in its assessment that could change in light of more evidence.
The subtype now accounts for about 43 percent of infections in the United States but was still responsible for less than 2.5 percent of Covid cases in the EU in December. XBB.1.5 cases have been reported in thirty-eight countries.
“There are currently no indications that the infectivity of XBB.1.5 differs from previously circulating omicron sub-lineages,” the agency said.
The subform is very similar to XBB.1 but has an additional change in its spike protein.