NEW YORK, Dec 20: In response to the rapid global spread of the new COVID-19 variant JN.1, the World Health Organization (WHO) announced its decision to upgrade the classification of JN.1 to a standalone "variant of interest." Although health officials emphasize that JN.1 has not been associated with different or more severe symptoms compared to previous variants, the WHO underscores the variant's swift dissemination as the basis for its reclassification from its predecessor, BA.2.86.

JN.1, a closely-related descendant of the highly mutated BA.2.86, originally flagged by the WHO as a "variant of interest" in August, has become the predominant lineage globally. The "variant of interest" status is a tier below the more concerning "variant of concern," such as Delta or Omicron. The WHO, exercising caution, has refrained from elevating any new variants to the "concern" threshold since the original Omicron classification in 2021.

The criteria for a "variant of interest" include genetic changes impacting key characteristics of the virus and a potential emerging risk to global public health. The WHO stresses that the Greek letter nomenclature will be reserved for variants of concern, with JN.1 currently falling into the former category.

While the Centers for Disease Control and Prevention (CDC) in the United States has not yet classified JN.1 as a "variant of interest," global health officials emphasize that the symptoms remain consistent with other strains, and there is no indication of increased severity at this time.

Early data from Belgium and Singapore suggest that JN.1 may lead to similar or lower hospitalization risks. However, concerns arise regarding JN.1's ability to outcompete other strains, potentially evading immune defenses and contributing to accelerated infections.

The CDC estimates project JN.1 as the fastest-growing strain in the U.S., constituting over 20% of cases nationwide, on track to become the dominant variant. This development occurs against the backdrop of elevated COVID-19 trends in the U.S., particularly in Midwestern regions where emergency room visits from COVID-19 have surged.

Despite concerns about JN.1's impact on vaccine effectiveness, this season's updated COVID-19 vaccines are expected to enhance protection against the variant. The WHO panel has opted against altering vaccine formulations for now, emphasizing the likely effectiveness of existing vaccines against JN.1.

As the US reports a significant share of JN.1 sequences globally, health officials remain vigilant in monitoring the variant's trajectory and impact, with new variant estimates anticipated from the CDC in the coming days.