An Understanding of the New SARS-Cov-2 Variant-Arcturus, A Subvariant of Omicron |Biomedgrid

In late March 2023, a new subvariant of SARS-CoV-2 called XBB.1.16 or Arcturus, emerged and was detected in various countries. This subvariant is linked with a 1.27-fold and 1.17-fold increase in adequate Reproductive Number (Re) compared to the XBB.1 and XBB.1.5 subvariants, respectively, indicating its potential for rapid spread. Previously, the XBB.1.5 and XBB.1.9 subvariants of the Omicron variant, which contain the F486P substitution in their Spike Protein (S protein), were circulating widely across the world [1]. Following its detection in multiple countries, including India, on March 30, 2023, the World Health Organization (WHO) began monitoring XBB.1.16 due to its increased transmissibility. According to the GISAID database, XBB.1.16 has been the most prevalent SARS-CoV-2 variant in India since February 2023, which is attributed to the high immune evasion and hACE2 binding of XBB variants caused by an F486S amino acid substitution in the spike glycoprotein [2]. By the end of March 2023, XBB.1.16 had outcompeted other variants in India, leading to the WHO classifying it as a variant under monitoring on March 30, 2023 [1].