Omicron Sub-Variant May Cause New Surge of Infections in Current Wave

(Bloomberg) -- A sub-variant of the omicron coronavirus strain, known as BA.2, is spreading rapidly in South Africa and may cause a second surge of infections in the current wave, one of the country's top scientists said.

BA.2 is causing concern as studies show that it appears to be more transmissible than the original omicron strain, the discovery of which was announced by South Africa and Botswana in November. 

Research also shows that getting a mild infection with either of the two strains may not give a robust enough immune response to protect against another omicron infection. There's no indication that the sub-variant causes more severe disease from infection surges seen in Denmark and the U.K.

The omicron wave of infections “may end up like a camel,” Tulio de Oliveira, a bio-informatics professor who runs gene-sequencing institutions and advises the government on the pandemic, said at a presentation at Stellenbosch University on Wednesday. “A wave with another hump.”

So far the strain has infected a significant number of people in seven of South Africa's nine provinces, is dominant in Limpopo region and is on the verge of becoming so in Gauteng, the most populous province, according to de Oliveira's presentation. 

Still, while South Africa was the first country to experience a major omicron wave the number of infections has tapered off. On Tuesday the country reported 3,085 new cases, down from a record of almost 27,000 on Dec. 15. The original omicron strain is itself significantly more transmissible than earlier variants such as delta, but appears to cause milder disease.

De Oliveira was involved in the discovery of the beta variant in South Africa in late 2020.

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