New Delhi, March 19 (IANS) – A recent study has revealed that the latest Covid-19 vaccines do not offer increased protection against the JN.1 variant, a off-shoot of the Omicron lineage. The variant, initially identified in Luxembourg, has been classified as a variant of interest by the WHO due to its rapid spread and immune evasion properties caused by the additional mutation L455S in the spike protein.
The study, which has not yet undergone peer-review, focused on the efficacy of XBB 1.5 boosters on the JN.1 variant among 76 individuals. While the vaccine showed better coverage overall, the JN.1 variant was still able to evade the immune response. Researcher Alejandro B. Balazs noted that “few escape boosted sera” but the JN.1 variant managed to do so, despite increased titers against newer variants with an updated booster.
Furthermore, the study found that newly emerging Covid variants have developed more efficient ways of entering cells, beyond the common entry point- ACE2. The team discovered that mutations contribute significantly to the ability of the virus to infect cells, indicating that variant selection is optimizing both antibody escape and viral entry. Spikes from variants post-BA.1 were found to be up to 30-fold better at infecting target cells than the wild-type SARS-CoV-2 spike.
While seasonal boosters were found to enhance immunity against new strains, the study emphasizes the need for novel approaches to control the transmission of SARS-Cov-2, given the immune escape potential of these variants.
The findings of this study highlight the ongoing challenges in combating the evolving Covid-19 variants and the importance of continued research and development of vaccines to effectively control the spread of the virus.
