According to the WHO, BA.2 is about 30% more infectious than BA.1.
It has a distinct genetic sequence, including some amino acid differences in the spike protein and other proteins which may make it more transmissible than the original omicron.
Some data shows that BA.2 may be more likely than BA.1 to spread between people who live in the same home.
BA.2’s increased transmissibility is why it is able to overtake and replace BA.1, not because it can avoid the body’s immune defenses. BA.2 is only slightly better than BA.1 at staying away from the antibodies created by vaccines, natural infection or both.