New Delhi, June 7 -- The World Health Organisation has assessed the global health risk from Covid-19 variant NB.1.8.1, Sars-CoV-2 family virus most prevalent today, as low, despite rising cases in several countries. The UN health body said on Friday that current evidence does not suggest the variant causes more severe illness than others in circulation. While cases and hospitalisations are increasing in some regions, this may be attributed to factors such as lower vaccination rates rather than the variant's severity. NB.1.8.1, first detected in a sample collected on January 22, 2025, is a descendant of the XDV.1.5.1 lineage, which itself descended from JN.1-a lineage of the Omicron variant BA.2.86. The variant carries six additional spike mutations that could affect its behaviour. Notably, mutations at position 445 may enhance binding to the hACE2 receptor, potentially increasing transmissibility. Meanwhile, changes at positions 435 and 478 could help the variant evade certain antibodies. In India, NB.1.8.1 is circulating alongside other variants including JN.1, LF.7, and XFG. The virus has shown increased prevalence both domestically and globally since mid-April, according to sources familiar with the monitoring....