Covid-19 cases are an all-time low in India, but the threat of more variants and their mutations still continue to loom over the country that has already experienced three waves of the pandemic. The World Health Organisation has already said that it is studying several sub-lineages of the Omicron variants of coronavirus that caused the third wave, including BA.1, BA.1.1, BA.2, and BA.3, and tracking their intensity through real-world data.While we all are familiar with the BA.1 and BA.2 sub-variants of Omicron, the WHO has now said that it is monitoring the BA.3 sub-lineage to assess if it causes “more severe disease”.Infectious Disease Epidemiologist and COVID-19 Technical Lead, Maria Van Kerkhove on March 5 said at the World Health Organisation that the severity of the BA.2 and BA.1 sub-variants is similar, and also notified about the BA.3 sub-variant of Omicron. “The most prominent ones that are detected worldwide are BA.1, BA.1.1 and BA.2. There’s also BA.3 and other sub-lineages as well,” she said.What is the Omicron BA.3 Variant?The WHO classified Omicron as the fifth variant of concern after its emergence in Botswana, and also fount that it was the most mutated variant of the virus. A study named ‘Emergence of Omicron third lineage BA.3 and its importance’, and published in the Journal of Medical Virology in January also showed that while the BA.1 and BA.2 had different spike proteins, there were no specific mutations in BA.3 spike proteins. The BA.3 was a combination of BA.2 and BA.1 spike proteins, it said.Is BA.3 Lineage of Omicron Variant Contagious?Discovered first in northwestern South Africa, only 0.013 per cent of the total genome sequences added to the GISAID was of the BA.3 Omicron sub-lineage that also had fewer mutations, the study showed.“BA.3 lineage caused the lowest number of cases in these three lineages. Therefore, it can be speculated that the reason for the BA.3 lineage spreading at very low speeds and causing fewer cases may have been due to the loss of six mutations from BA.1 or obtaining two mutations from BA.2,” it said.However, it also noted that though Omicron has so far shown to cause milder infections, “it is also possible to develop some mutations” that may result in serious illnesses.Read all the Latest News, Breaking News and Assembly Elections Live Updates here.