The World Health Organization has issued another regulation on the antigen composition of COVID-19 vaccines. It maintains the priority use of monovalent preparations of the JN.1 (JN.1 or KP.2) variant of the SARS-CoV-2 coronavirus, first recommended in April 2024 and confirmed in December of that year. This variant of the virus, with its characteristic L455S mutation, was first identified in August 2023 and quickly became dominant. The new regulation also approves monovalent vaccines of the LP.8.1 variant of the coronavirus for the first time as an acceptable alternative.
Ongoing monitoring of the antigenic composition of viruses and the immune response to infection and vaccination by the WHO Technical Advisory Group on Covid-19 Vaccine Composition (TAG-CO-VAC) shows that the currently circulating virus variants originated from JN.1 and remain close to it in antigenic composition. Among them, the weekly proportion of LP.8.1 and LF.7 variants continues to increase, while the proportion of other variants under surveillance, such as KP.3, KP.3.1.1, XEC and LB.1, is decreasing.