geneva a subvariant of the highly contagious omicron coronavirus strain which some studies indicate could be even more infectious than the original version has been detected in 57 countries the who said tuesdaythe fastspreading and heavily mutated omicron variant has rapidly become the dominant variant worldwide since it was first detected in southern africa 10 weeks agoin its weekly epidemiological update the world health organization said that the variant which accounts for over 93 percent of all coronavirus specimens collected in the past month counts several sublineages ba1 ba11 ba2 and ba3the ba1 and ba11 the first versions identified still account for over 96 percent of all the omicron sequences uploaded to the gisaid global science initiative it saidbut there has been a clear rise in cases involving ba2 which counts several different mutations from the original including on the spike protein that dots the viruss surface and is key to entering human cellsba2 designated sequences have been submitted to gisaid from 57 countries to date who said adding that in some countries the subvariant now accounted for over half of all omicron sequences gatheredthe un health agency said little was known yet about the differences between the subvariants and called for studies into its characteristics including its transmissibility how good it is at dodging immune protections and its virulenceseveral recent studies have hinted that ba2 is more infectious than the original omicronmaria van kerkhove one of the whos top experts on covid told reporters tuesday that information about the subvariant was very limited but that some inital data indicated ba2 had a slight increase in growth rate over ba1omicron in general is known to cause less severe disease than previous coronavirus variants that have wreaked havoc like delta and van kerkhove said there so far was no indication that there is a change in severity in the ba2 subvariantshe stressed though that regardless of the strain covid remained a dangerous disease and people should strive to avoid catching itwe need people to be aware that this virus is continuing to circulate and its continuing to evolve she saidits really important that we take measures to reduce our exposure to this virus whichever variant is circulating