(WXYZ) — The World Health Organization is tracking four different lineages of the highly contagious omicron variant.
BA.1 is the current dominant version, but cases of the subvariant BA.2 are expected to increase worldwide.
The BA.2 omicron subvariant is also called the “stealth” variant because the mutations it has make it harder to identify. Now, research has found that BA.2 is about 1.5 times more transmissible than the original omicron variant BA.1. So, it has the ability to spread faster.
But does it have the ability to reinfect people who caught the first version of omicron?
When looking at reports from Africa, we can see that BA.2 is increasing in areas where there were once high cases of the original omicron variant. But that doesn’t mean people are getting re-infected. It could be that the virus is just finding new individuals to infect. Having said that, a study in the United Kingdom found two-thirds of people who had previously caught COVID-19 were reinfected with omicron. So prior infection doesn’t mean lasting protection and we know that antibodies wane over time. Since BA.1 and BA.2 are sister variants, they could be close enough that getting infected with one protects you against the other. But to truly answer that we need more data.
So far it looks like BA.2 does not cause more severe disease nor does it increase hospitalization rates when compared with BA.1. So, that’s good news but once again, it's still early and we need more research.
As for our vaccines, a recent study in Denmark found BA.2 has immune-evasive properties, which can lower the protective effect of vaccination against infection. So, BA.2 appears to be better at infecting vaccinated people than BA.1. But researchers found those who are vaccinated didn't spread the virus as easily as people who were unvaccinated. And the study also found people who are vaccinated and those vaccinated and boosted were still overall less likely to get infected with either BA.1 or BA.2.
So once again, another study shows our vaccines are working well. They’re protecting people against symptomatic disease and they're keeping people out of the hospitals. So, please get vaccinated and boosted when you can.
Additional Coronavirus information and resources:
View a global coronavirus tracker with data from Johns Hopkins University.
See complete coverage on our Coronavirus Continuing Coverage page.
