A new Omicron subvariant is spreading across the U.S., the Centers for Disease Control and Prevention data said Tuesday.

Driving the news: The subvariant, BA.2.12.1, accounts for about 20% of new cases across the U.S. and is an offshoot of the BA.2 version of Omicron, which has been the dominant variant since late March, NBC News reports.

• The Omicron BA.2 subvariant is still the dominant strain, making up about 75% of all cases, according to the CDC.

The big picture: The New York State Department of Health said last week that BA.2.12 and BA.2.12.1 — both sub-lineages of the BA.2 Omicron variant — are likely causing a spike in cases in upstate New York.

• "We are alerting the public to two Omicron subvariants, newly emerged and rapidly spreading in upstate New York, so New Yorkers can act swiftly," State Health Commissioner Dr. Mary T. Bassett said in a statement.
• Covid is rising across the U.S., with the Northeast accounting for many of the new cases, Axios' Tina Reed and Kavya Beheraj report.
• Nationwide, there were an average of more than 31,500 cases, up 14% from the nearly 28,000 cases reported two weeks ago.

Go deeper ... U.S. COVID cases on the rise again