Two new sublineages of the Omicron coronavirus variant- BA.4 and BA.5- can dodge antibodies from earlier infection well enough to trigger a new wave, but are far less able to thrive in the blood of people vaccinated against COVID-19, South African scientists have found, the Reuters reported on Sunday.

from Times of India https://timesofindia.indiatimes.com/life-style/health-fitness/health-news/coronavirus-study-claims-new-covid-wave-imminent-as-new-variants-can-dodge-immunity-what-we-know-so-far/photostory/91255360.cms