JOHANNESBURG (Reuters) - South African scientists have discovered that two new sublineages of the Omicron coronavirus variant can evade antibodies from previous infections well enough to cause a new wave, but are far less able to thrive in the blood of people who have been vaccinated against COVID-19.
The experts were looking into Omicron's BA.4 and BA.5 sublineages, which were added to the World Health Organization's monitoring list last month. They collected blood samples from 39 people who had been infected with Omicron when it first appeared at the end of last year.
The other 24 were not vaccinated. Fifteen were inoculated, eight with Pfizer's injection and seven with J&J's.
"The vaccinated group exhibited around a 5-fold higher neutralisation capacity... and should be better protected," according to the report, which was issued as a pre-print over the weekend.
Nearly 30% of new cases are thought to be caused by the COVID-19 subvariant.