Antibodies from people who received updated COVID-19 vaccines can still neutralise the new PJ.2.1 variant in laboratory tests, according to research reported on Tuesday 10 November by Jagran Josh and The Daily Jagran. The finding is the first reassurance about the variant since it began spreading more widely this autumn, although the tests were carried out in a laboratory and do not by themselves prove how well vaccines protect against infection in the real world.
PJ.2.1 was first identified in Ontario, Canada, in May 2026, with the earliest documented sample collected on 2 May, according to the reports, which draw on a study by Markus Hoffmann and colleagues published in the Journal of Infection on 24 October 2026. The variant descends from the MC.10.1.7 branch of the JN.1 lineage, and the researchers describe it as a "saltation variant" because it carries an unusually large number of genetic mutations rather than changing gradually over time.
Genomic surveillance in Ontario showed the variant's share of sequenced coronavirus samples climbing from about one percent in late June to 25.2 percent between 20 September and 17 October, up from 16.9 percent in the previous four weeks, according to Jagran Josh. It has since been detected in the United States, where the first case was recorded in New York City on 30 June, as well as in Singapore, Australia, New Zealand, Israel, France and Spain. Readers should note this spread is the subject of a separate COCONOPS report published on 9 November; this article reports the new laboratory findings about vaccines.
In the laboratory, serum from people immunised with an adapted LP.8.1 vaccine neutralised PJ.2.1, although its neutralising sensitivity was about 1.8 times lower than against LP.8.1 itself, according to the reports. The researchers found stronger binding to the human ACE2 receptor and better entry into cells, but no conclusive proof that the variant produces more severe illness or spreads more efficiently than earlier strains, and there is no evidence so far that it causes more hospitalisations or deaths.
The World Health Organization had not listed PJ.2.1 as a variant of concern, a variant of interest or a variant under monitoring in its July 2026 list, according to Jagran Josh, and India's genomic surveillance consortium, INSACOG, has not confirmed any detection of the variant in India. Health agencies are continuing to monitor it, and the laboratory result suggests the current generation of updated vaccines stillecognises the variant — a finding that will be tested further as more real-world data arrives.