The National Institute of Health (NIH) has detected the first case of Omicron sub-variant BA.2.12.1 in Pakistan. According to NIH’s spokesperson, this new sub-variant is causing increasing number of cases in different countries. He said that the best preventive measure “besides mask-wearing at crowded places, is COVID-19 vaccination.” He added, “We strongly recommend getting vaccinated and all those due for booster must get the shots immediately.” According to health experts, Omicron is a variant of the SARS-CoV-2 virus that was first discovered in Botswana on November 11, 2021 and designated a variant of concern by the WHO on November 26. They said that Omicron has multiple different lineages including the original Omicron BA.1 (B.1.1.529) and also BA.2 and BA.3. BA.2 is more infectious than BA.1 and has now taken over BA.1 to become the new dominant form of the SARS-CoV-2 virus worldwide, they added. BA.2 shares many of these same mutations as the original Omicron variant, but also has 28 unique genetic changes of its own. Four of these genetic changes are in the spike protein, which explains why some of its characteristics are different to the original Omicron variant (BA.1), including the fact it appears to be approximately 30 to 50% more infectious than BA.1.