The latest set of Covid-19 vaccines offered no increased protection against the JN.1 variant, which continues to circulate, according to a study.
JN.1, from the lineage of Omicron, is an off-spin of BA.2.86.
The variant, first detected in Luxembourg in August, was classified as a variant of interest (VOI) by the World Health Organisation (WHO) due to its rapid spread.
The additional mutation L455S in the spike protein of JN.1 is believed to have provided the variant with immune-evasion properties.
The study, appearing on a preprint site and not peer-reviewed yet, examined the efficacy of XBB 1.5 boosters on the JN.1 variant among 76 people. The findings showed that the vaccine provided better coverage overall, but the globally dominant JN.1 managed to evade them.