Experts are also calling BA.2 a "stealth omicron," as there's a key difference in its genetic sequence that makes it harder to track.
Right now, there are only a handful of concerning COVID-19 variants.
In the wake of local campus closures due to COVID, we looked into how districts determine the threshold on which it reverts to closing a school.
As classes resume, some districts are defying Gov. Greg Abbott's orders by requiring masks while others are keeping them optional.
Gov. Kate Brown's order -- which will take effect Friday -- is generally for everyone ages 5 and up, regardless of vaccination status.
The study is in line with others from around the world showing delta's increased tendency to cause largely minor infections among fully vaccinated people.