4:13 PM, Feb 27, 2020


BA.2 subvariant of Omicron on the rise, research shows that it can slip past antibodies of other variants

Posted at 3:19 PM, Feb 18, 2022

(WXYZ) — A new study suggests BA.2, the subvariant of Omicron, can cause more severe disease than the original Omicron BA.1.  It also appears to be more resistant to some treatments used to fight infection. 

Lab experiments from Japan found BA.2 is very different from the original Omicron variant. It has dozens of gene changes that are so distinct that researchers feel that BA.2 should get its Greek letter.

How did the scientists discover that BA.2 can cause more severe disease than the original Omicron variant? Well, in lab studies, animals infected with BA.2 ended up getting sicker than animals infected with BA.1. BA.2 also caused worse lung function compared to BA.1. When tissue samples were examined, more damage was seen in the animals with BA.2 than with BA.1.

What's concerning is this study also found the BA.2 lineage can replicate itself faster than BA.1. It’s better at making cells stick to each other. If large clumps develop, the medical term is called Syncytia, which allows the virus to make copies of itself much faster. Delta was good at this, which is one reason scientists believed it was so damaging to the lungs.

Real work evidence is mixed regarding BA.2 and how severe it can be. For example, if you look at the United Kingdom and South Africa, hospitalizations have declined. But in Denmark, hospitalizations and deaths have been on the rise.

A study found that BA.2 can be resistant to Sotrovimab. That’s a monoclonal antibody treatment given to people who are at high risk of developing severe disease. Blood tests suggest BA.2 can slip past antibodies of people who’ve been infected with the Alpha and Delta variants. Research suggests BA.2 is between 30 and 50% more contagious than the original Omicron variant.

Right now, BA.2 only accounts for roughly 4% of US COVID-19 infections. Blood tests show people recently infected with BA.1. The original Omicron has some protection against infection with BA.2, especially if they were also vaccinated. Those who have avoided the infection, getting a booster shot restored protection, making illness after infection about 74% less likely.

Additional Coronavirus information and resources:

View a global coronavirus tracker with data from Johns Hopkins University.

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