The heavily mutated and highly infectious sub-variant of the omicron coronavirus strain, BA.2, has rapidly become the dominant global variant and has been detected in 57 countries, the World Health Organisation (WHO) said Tuesday.
The WHO, in its weekly epidemiological update, revealed that "BA.2-designated sequences have been submitted to the Global Initiative on Sharing Avian Influenza Data (GISAID) from 57 countries to date," and in some countries, the sub-variant now accounts for more than half of all omicron sequences gathered.
The BA.2 variant was first reported in South Africa 10 weeks ago and is now spreading quickly through Denmark, the UK, US, Canada, India, Sweden, Singapore and the Philippines.
"It’s premature for any country either to surrender, or to declare victory. This virus is dangerous, and it continues to evolve before our very eyes. The WHO is currently tracking four sub-lineages of the omicron variant of concern, including BA.2," WHO chief Dr Tedros Adhanom Ghebreyesus warned.
Maria Van Kerkhove, one of the WHO's top experts on COVID, said that information about the sub-variant was limited but that some initial data indicated the BA.2 had “a slight increase in growth rate over BA.1”.
Kerkhove also said that although there was “no indication there is a change in severity” in the BA.2 sub-variant, it is imperative that people continue to take precautions to avoid catching it.
"We need people to be aware that this virus is continuing to circulate and it’s continuing to evolve. It's really important that we take measures to reduce our exposure to this virus, whichever variant is circulating," Kerkhove said.
In Denmark, BA.2 accounted for 45 percent of the country’s COVID-19 cases last month, up from 20 percent the week before, according to surveillance data.
Last week, India's National Centre for Disease Control (NCDC) director Sujeet Kumar Singh said that the prevalence of the omicron sub-lineage BA.2 is gradually gaining ground in the country, posing new challenges to the doctors and health experts in its diagnosis and treatment.